1
|
Dobson GP, Morris JL, Letson HL. Transforming research to improve therapies for trauma in the twenty-first century: an alternative perspective. Crit Care 2024; 28:135. [PMID: 38654282 PMCID: PMC11036738 DOI: 10.1186/s13054-024-04913-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Accepted: 04/13/2024] [Indexed: 04/25/2024] Open
Affiliation(s)
- Geoffrey P Dobson
- Heart, Sepsis and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, 1 James Cook Drive, Townsville, QLD, 4811, Australia.
| | - Jodie L Morris
- Heart, Sepsis and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, 1 James Cook Drive, Townsville, QLD, 4811, Australia
| | - Hayley L Letson
- Heart, Sepsis and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, 1 James Cook Drive, Townsville, QLD, 4811, Australia
| |
Collapse
|
2
|
Dobson GP, Morris JL, Letson HL. Pathophysiology of severe burn injuries: new therapeutic opportunities from a systems perspective. J Burn Care Res 2024:irae049. [PMID: 38517382 DOI: 10.1093/jbcr/irae049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Indexed: 03/23/2024]
Abstract
Severe burn injury elicits a profound stress response with the potential for high morbidity and mortality. If polytrauma is present, patient outcomes appear to be worse. Sex-based comparisons indicate females have worse outcomes than males. There are few effective drug therapies to treat burn shock and secondary injury progression. The lack of effective drugs appears to arise from the current treat-as-you-go approach rather than a more integrated systems approach. In this review, we present a brief history of burns research and discuss its pathophysiology from a systems' perspective. The severe burn injury phenotype appears to develop from a rapid and relentless barrage of damage-associated molecular patterns (DAMPs), pathogen-associated molecular patterns (PAMPs) and neural afferent signals, which leads to a state of hyperinflammation, immune dysfunction, coagulopathy, hypermetabolism and intense pain. We propose that if the central nervous system (CNS) control of cardiovascular function and endothelial-glycocalyx-mitochondrial coupling can be restored early, these secondary injury processes may be minimized. The therapeutic goal is to switch the injury phenotype to a healing phenotype by reducing fluid leak and maintaining tissue O2 perfusion. Currently, no systems-based therapies exist to treat severe burns. We have been developing a small-volume fluid therapy comprising adenosine, lidocaine and magnesium (ALM) to treat hemorrhagic shock, traumatic brain injury and sepsis. Our early studies indicate that the ALM therapy holds some promise in supporting cardiovascular and pulmonary functions following severe burns. Future research will investigate the ability of ALM therapy to treat severe burns with polytrauma and sex disparities, and potential translation to humans.
Collapse
Affiliation(s)
- Geoffrey P Dobson
- Heart and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, Queensland, Australia
| | - Jodie L Morris
- Heart and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, Queensland, Australia
| | - Hayley L Letson
- Heart and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, Queensland, Australia
| |
Collapse
|
3
|
de Souza JC, Letson HL, Gibbs CR, Dobson GP. The burden of head trauma in rural and remote North Queensland, Australia. Injury 2024; 55:111181. [PMID: 37951809 DOI: 10.1016/j.injury.2023.111181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 10/29/2023] [Accepted: 10/31/2023] [Indexed: 11/14/2023]
Abstract
BACKGROUND Head trauma is a leading cause of death and disability worldwide. Young males, Indigenous people, and rural/remote residents have been identified as high-risk populations for head trauma, however, Australian research is limited. Our aim was to define and describe the incidence, demographics, causes, prehospital interventions, and outcomes of head trauma patients transported by aeromedical services within North Queensland, Australia. We hypothesized that young, Indigenous males living remotely would be disproportionately affected by head trauma. METHODS We conducted a retrospective study of all head trauma patients transferred by air to or between Townsville, Cairns, Mount Isa and Mackay Hospitals between January 1, 2016 and December 31, 2018. Patients were identified from the Trauma Care in the Tropics data registry and followed for a median 30-months post-injury. Primary endpoints were patient and injury characteristics. Secondary outcome measures were hospital stay and mortality. RESULTS A total of 981 patients were included and 31.1 % were Indigenous. Sixty-seven percent of injuries occurred remotely and the median time from injury to hospital was 5.8-hours (range 67-3780 min). Eighty percent of severe head injuries occurred in males (p = 0.007). Indigenous and remote patients were more likely to sustain mild injuries. The most common mechanism of injury overall was vehicle accident (37.5 %), compared to assault in the Indigenous subgroup (46.6 %, p<0.001). The overall mortality rate was 4.9 %, with older age and lower initial Glasgow Coma Score significant predictors of in-hospital mortality. Prehospital intubation was associated with a 7-fold increased risk of mortality (p = 0.056), while patients that received tranexamic acid (TXA) were almost 5-times more likely to die. CONCLUSIONS In North Queensland, young Indigenous males are at highest risk of traumatic head injuries. Vehicle accidents are an important preventable cause of head injury in the region. TXA administration is an important consideration for remote head trauma retrievals, in which time to emergency care is prolonged. Appropriate treatment and risk stratification strategies considering time to definitive care, severity of injury, and other prehospital patient factors require further investigation.
Collapse
Affiliation(s)
- Julia Chequer de Souza
- College of Medicine & Dentistry, James Cook University, 1 James Cook Drive, Townsville, Queensland 4811, Australia
| | - Hayley L Letson
- College of Medicine & Dentistry, James Cook University, 1 James Cook Drive, Townsville, Queensland 4811, Australia.
| | - Clinton R Gibbs
- Retrieval Services Queensland, 100 Angus Smith Drive, Douglas, Queensland 4814, Australia; Emergency Department, Townsville University Hospital, Townsville Hospital and Health Service, 100 Angus Smith Drive, Douglas, Queensland 4814, Australia; College of Public Health, Medical and Veterinary Sciences, James Cook University, 1 James Cook Drive, Townsville, Queensland 4811, Australia
| | - Geoffrey P Dobson
- College of Medicine & Dentistry, James Cook University, 1 James Cook Drive, Townsville, Queensland 4811, Australia
| |
Collapse
|
4
|
Davenport LM, Letson HL, Dobson GP. Lung Protection After Severe Thermal Burns With Adenosine, Lidocaine, and Magnesium (ALM) Resuscitation and Importance of Shams in a Rat Model. J Burn Care Res 2024; 45:216-226. [PMID: 37602979 PMCID: PMC10768784 DOI: 10.1093/jbcr/irad127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Indexed: 08/22/2023]
Abstract
The management of severe burns remains a complex challenge. Adenosine, lidocaine, and magnesium (ALM) resuscitation therapy has been shown to protect against hemorrhagic shock and traumatic injury. The aim of the present study was to investigate the early protective effects of small-volume ALM fluid resuscitation in a rat model of 30% total body surface area (TBSA) thermal injury. Male Sprague-Dawley rats (320-340 g; n = 25) were randomly assigned to: 1) Sham (surgical instrumentation and saline infusion, without burn, n = 5), 2) Saline resuscitation group (n = 10), or 3) ALM resuscitation group (n = 10). Treatments were initiated 15-min after burn trauma, including 0.7 mL/kg 3% NaCl ± ALM bolus and 0.25-0.5 mL/kg/h 0.9% NaCl ± ALM drip, with animals monitored to 8.25-hr post-burn. Hemodynamics, cardiac function, blood chemistry, hematology, endothelial injury markers and histopathology were assessed. Survival was 100% for Shams and 90% for both ALM and Saline groups. Shams underwent significant physiological, immune and hematological changes over time as a result of surgical traums. ALM significantly reduced malondialdehyde levels in the lungs compared to Saline (P = .023), and showed minimal alveolar destruction and inflammatory cell infiltration (P < .001). ALM also improved cardiac function and oxygen delivery (21%, P = .418 vs Saline), reduced gut injury (P < .001 vs Saline), and increased plasma adiponectin (P < .001 vs baseline). Circulating levels of the acute phase protein alpha 1-acid glycoprotein (AGP) increased 1.6-times (P < .001), which may have impacted ALM's therapeutic efficacy. We conclude that small-volume ALM therapy significantly reduced lung oxidative stress and preserved alveolar integrity following severe burn trauma. Further studies are required to assess higher ALM doses with longer monitoring periods.
Collapse
Affiliation(s)
- Lisa M Davenport
- Heart and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, Queensland 4811, Australia
| | - Hayley L Letson
- Heart and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, Queensland 4811, Australia
| | - Geoffrey P Dobson
- Heart and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, Queensland 4811, Australia
| |
Collapse
|
5
|
Letson HL, Morris JL, Dobson GP. Changes in plasma alpha-1 acid glycoprotein following hemorrhagic trauma: Possible role in dose differences of ALM drug therapy in rat and pig resuscitation. Pharmacol Res Perspect 2023; 11:e01133. [PMID: 37643751 PMCID: PMC10465298 DOI: 10.1002/prp2.1133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 08/03/2023] [Accepted: 08/06/2023] [Indexed: 08/31/2023] Open
Abstract
INTRODUCTION The binding of drugs to plasma proteins is an important consideration in drug development. We have reported that the dose of adenosine, lidocaine, and magnesium (ALM) fluid therapy for resuscitation from hemorrhagic shock is nearly 3-times higher for pigs than rats. Since lidocaine strongly binds to serum alpha-1-acid glycoprotein (AGP), the aim of the study was to investigate the effect of hemorrhagic shock on levels of AGP in rats and pigs. MATERIALS AND METHODS Healthy adult male Sprague-Dawley rats and female crossbred pigs (n = 33 each) underwent tail vein and peripheral ear vein blood sampling, respectively, to collect plasma for AGP measurements. Rats (n = 17) and pigs (n = 16) underwent surgical instrumentation and uncontrolled hemorrhage via liver resection, and were treated with 3% NaCl ± ALM IV bolus followed 60 min later by 4 h 0.9% NaCl ± ALM IV drip. Rats were monitored for 72 h with blood samples taken post-surgery, and at 5.25, 24, and 72 h. Pigs were monitored for 6 h with blood samples taken post-surgery, and at 60 min and 6 h. Plasma AGP was measured with rat- and pig-specific enzyme-linked immunosorbent assay kits. RESULTS Baseline AGP levels in rats were 3.91 μg/mL and significantly 83-fold lower than in pigs (325 μg/mL). Surgical instrumentation was associated with ~10-fold increases in AGP in rats and a 21% fall in pigs. AGP levels remained elevated in rats after hemorrhage and resuscitation (28-29 μg/mL). In contrast, no significant differences in plasma AGP were found in ALM- or Saline-treated pigs over the monitoring period. CONCLUSIONS We conclude that the trauma of surgery alone was associated with significant increases in AGP in rats, compared to a contrasting decrease in pigs. Higher levels of plasma AGP in pigs prior to hemorrhagic shock is consistent with the higher ALM doses required to resuscitate pigs compared with rats.
Collapse
Affiliation(s)
- Hayley L. Letson
- Heart and Trauma Research Laboratory, College of Medicine and DentistryJames Cook UniversityTownsvilleQueenslandAustralia
| | - Jodie L. Morris
- Heart and Trauma Research Laboratory, College of Medicine and DentistryJames Cook UniversityTownsvilleQueenslandAustralia
| | - Geoffrey P. Dobson
- Heart and Trauma Research Laboratory, College of Medicine and DentistryJames Cook UniversityTownsvilleQueenslandAustralia
| |
Collapse
|
6
|
Dobson GP, Morris JL, Letson HL. Adenosine, lidocaine and Mg 2+ update: teaching old drugs new tricks. Front Med (Lausanne) 2023; 10:1231759. [PMID: 37828944 PMCID: PMC10565858 DOI: 10.3389/fmed.2023.1231759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 09/11/2023] [Indexed: 10/14/2023] Open
Abstract
If a trauma (or infection) exceeds the body's evolutionary design limits, a stress response is activated to quickly restore homeostasis. However, when the injury severity score is high, death is often imminent. The goal of this review is to provide an update on the effect of small-volume adenosine, lidocaine and Mg2+ (ALM) therapy on increasing survival and blunting secondary injury after non-compressible hemorrhagic shock and other trauma and infective/endotoxemic states. Two standout features of ALM therapy are: (1) resuscitation occurs at permissive hypotensive blood pressures (MAPs 50-60 mmHg), and (2) the drug confers neuroprotection at these low pressures. The therapy appears to reset the body's baroreflex to produce a high-flow, hypotensive, vasodilatory state with maintained tissue O2 delivery. Whole body ALM protection appears to be afforded by NO synthesis-dependent pathways and shifting central nervous system (CNS) control from sympathetic to parasympathetic dominance, resulting in improved cardiovascular function, reduced immune activation and inflammation, correction of coagulopathy, restoration of endothelial glycocalyx, and reduced energy demand and mitochondrial oxidative stress. Recently, independent studies have shown ALM may also be useful for stroke, muscle trauma, and as an adjunct to Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA). Ongoing studies have further shown ALM may have utility for burn polytrauma, damage control surgery and orthopedic surgery. Lastly, we discuss the clinical applications of ALM fluid therapy for prehospital and military far-forward use for non-compressible hemorrhage and traumatic brain injury (TBI).
Collapse
Affiliation(s)
- Geoffrey P. Dobson
- Heart and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, QLD, Australia
| | | | | |
Collapse
|
7
|
Hoeger NS, Mittlmeier T, Vollmar B, Stratos I, Dobson GP, Rotter R. ALM Therapy Promotes Functional and Histologic Regeneration of Traumatized Peripheral Skeletal Muscle. Biology (Basel) 2023; 12:870. [PMID: 37372154 DOI: 10.3390/biology12060870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Revised: 06/07/2023] [Accepted: 06/13/2023] [Indexed: 06/29/2023]
Abstract
Skeletal muscle trauma is a common injury with a range of severity. Adenosine, lidocaine and Mg2+ (ALM) is a protective solution and improves tissue perfusion and coagulopathy. Male Wistar rats were anesthetized and subjected to standardized skeletal muscle trauma of the left soleus muscle with the protection of the neurovascular structures. Seventy animals were randomly assigned to saline control or ALM. Immediately after trauma, a bolus of ALM solution was applied intravenously, followed by a one-hour infusion. After 1, 4, 7, 14 and 42 days, the biomechanical regenerative capacity was examined using incomplete tetanic force and tetany, and immunohistochemistry was used to examine for proliferation and apoptosis characteristics. Biomechanical force development showed a significant increase following ALM therapy for incomplete tetanic force and tetany on days 4 and 7. In addition, the histological evaluation showed a significant increase in proliferative BrdU-positive cells with ALM therapy on days 1 and 14. Ki67 histology also detected significantly more proliferative cells on days 1, 4, 7, 14 and 42 in ALM-treated animals. Furthermore, a simultaneous decrease in the number of apoptotic cells was observed using the TUNEL method. ALM solution showed significant superiority in biomechanical force development and also a significant positive effect on cell proliferation in traumatized skeletal muscle tissue and reduced apoptosis.
Collapse
Affiliation(s)
- Nina Sarah Hoeger
- Department of Trauma and Reconstructive Surgery, University of Rostock, 18057 Rostock, Germany
| | - Thomas Mittlmeier
- Department of Trauma and Reconstructive Surgery, University of Rostock, 18057 Rostock, Germany
| | - Brigitte Vollmar
- Institute for Experimental Surgery, University of Rostock, 18057 Rostock, Germany
| | - Ioannis Stratos
- Department of Orthopaedic Surgery, University of Wuerzburg, 97074 Wuerzburg, Germany
| | - Geoffrey P Dobson
- Heart and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, QLD 4811, Australia
| | - Robert Rotter
- Department of Trauma and Reconstructive Surgery, University of Rostock, 18057 Rostock, Germany
| |
Collapse
|
8
|
Morris JL, Letson HL, Biros E, McEwen PC, Dobson GP. Female rats have a different healing phenotype than males after anterior cruciate ligament rupture with no intervention. Front Med (Lausanne) 2022; 9:976980. [DOI: 10.3389/fmed.2022.976980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 10/24/2022] [Indexed: 11/15/2022] Open
Abstract
Little is known on the sex-specific healing responses after an anterior cruciate ligament (ACL) rupture. To address this, we compared male and female Sprague-Dawley rats following non-surgical ACL rupture. Hematology, inflammation, joint swelling, range of motion, and pain-sensitivity were analyzed at various times over 31-days. Healing was assessed by histopathology and gene expression changes in the ACL remnant and adjacent joint tissues. In the first few days, males and females showed similar functional responses after rupture, despite contrasting hematology and systemic inflammatory profiles. Sex-specific differences were found in inflammatory, immune and angiogenic potential in the synovial fluid. Histopathology and increased collagen and fibronectin gene expression revealed significant tissue remodeling in both sexes. In the ACL remnant, however, Acta2 gene expression (α-SMA production) was 4-fold higher in males, with no change in females, indicating increased fibroblast-to-myofibroblast transition with higher contractile elements (stiffness) in males. Females had 80% lower Pparg expression, which further suggests reduced cellular differentiation potential in females than males. Sex differences were also apparent in the infrapatellar fat pad and articular cartilage. We conclude females and males showed different patterns of healing post-ACL rupture over 31-days, which may impact timing of reconstruction surgery, and possibly clinical outcome.
Collapse
|
9
|
Dobson GP, Morris JL, Letson HL. Why are bleeding trauma patients still dying? Towards a systems hypothesis of trauma. Front Physiol 2022; 13:990903. [PMID: 36148305 PMCID: PMC9485567 DOI: 10.3389/fphys.2022.990903] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 08/12/2022] [Indexed: 12/14/2022] Open
Abstract
Over the years, many explanations have been put forward to explain early and late deaths following hemorrhagic trauma. Most include single-event, sequential contributions from sympathetic hyperactivity, endotheliopathy, trauma-induced coagulopathy (TIC), hyperinflammation, immune dysfunction, ATP deficit and multiple organ failure (MOF). We view early and late deaths as a systems failure, not as a series of manifestations that occur over time. The traditional approach appears to be a by-product of last century’s highly reductionist, single-nodal thinking, which also extends to patient management, drug treatment and drug design. Current practices appear to focus more on alleviating symptoms rather than addressing the underlying problem. In this review, we discuss the importance of the system, and focus on the brain’s “privilege” status to control secondary injury processes. Loss of status from blood brain barrier damage may be responsible for poor outcomes. We present a unified Systems Hypothesis Of Trauma (SHOT) which involves: 1) CNS-cardiovascular coupling, 2) Endothelial-glycocalyx health, and 3) Mitochondrial integrity. If central control of cardiovascular coupling is maintained, we hypothesize that the endothelium will be protected, mitochondrial energetics will be maintained, and immune dysregulation, inflammation, TIC and MOF will be minimized. Another overlooked contributor to early and late deaths following hemorrhagic trauma is from the trauma of emergent surgery itself. This adds further stress to central control of secondary injury processes. New point-of-care drug therapies are required to switch the body’s genomic and proteomic programs from an injury phenotype to a survival phenotype. Currently, no drug therapy exists that targets the whole system following major trauma.
Collapse
|
10
|
Engstrom N, Dobson GP, Ng K, Lander K, Win K, Gupta A, Letson HL. Validation of CalECG software for primary prevention heart failure patients: Reducing inter-observer measurement variability. J Electrocardiol 2022; 74:128-133. [PMID: 36191576 DOI: 10.1016/j.jelectrocard.2022.09.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Revised: 08/09/2022] [Accepted: 09/19/2022] [Indexed: 12/13/2022]
Abstract
BACKGROUND In primary prevention heart failure patients the 12‑lead electrocardiogram (ECG) may be useful for the prediction of ventricular arrhythmias. However, inter-observer measurement variability first needs to be identified and any software used, validated. OBJECTIVE To compare manual ECG measures with CalECG software and to assess the reliability of visual recognition of fragmented QRS (fQRS) by advanced cardiology trainees. METHODS 30 pre-implant ECGs were assessed on patients who met guidelines for primary prevention Implantable Cardiac Defibrillator. Parameters included RR, PR, QT, QRS duration, axis location, fQRS and T wave peak to T wave end (TpTe). ECGs were analyzed by members of the cardiology department with different levels of experience, and compared to CalECG software. Interobserver agreement was assessed using Fleiss' Kappa (κ) and intraclass correlation coefficients (ICC). Pearson correlation coefficient (r) was used to compare human and software measures. RESULTS Strong/very strong correlation was recorded across manual ECG measures (ICC = 0.749-0.979, p ≤ 0.0001) with moderate/strong correlation for TpTe (ICC = 0.547-0.765, p ≤ 0.001). Advanced cardiology trainees demonstrated substantial agreement on ECG interpretation (κ = 0.788, p ≤ 0.0001), however, reliability of fQRS assessment was only moderate for identification (κ = 0.5, p ≤ 0.0001) and fair for location (κ = 0.295, p = 0.001). CalECG software showed strong/very strong correlation with manual measurement for standard measures (r = 0.756-0.977, p ≤ 0.001). Concordance between human and software TpTe measurements varied between leads, with V5 showing a non-significant weak correlation (r = 0.197). CONCLUSION CalECG software showed strong/very strong correlation with standard manual measures which affirms its use in ECG analysis. Advanced cardiology trainees showed greater variability in the identification and location of fQRS.
Collapse
Affiliation(s)
- Nathan Engstrom
- College of Medicine & Dentistry, Heart and Trauma Research Laboratory, James Cook University, 1 James Cook Drive, Townsville, QLD 4811, Australia; Cardiac Investigations, Townsville University Hospital, 100 Angus Smith Drive, Douglas, QLD 4814, Australia.
| | - Geoffrey P Dobson
- College of Medicine & Dentistry, Heart and Trauma Research Laboratory, James Cook University, 1 James Cook Drive, Townsville, QLD 4811, Australia.
| | - Kevin Ng
- Cardiology Clinic, Cairns Hospital, 165 Esplanade, Cairns, QLD 4870, Australia.
| | - Krystle Lander
- Cardiology Department, Townsville University Hospital, 100 Angus Smith Drive, Douglas, QLD 4814, Australia.
| | - Kyi Win
- Cardiology Department, Townsville University Hospital, 100 Angus Smith Drive, Douglas, QLD 4814, Australia.
| | - Anudeep Gupta
- Cardiology Department, Townsville University Hospital, 100 Angus Smith Drive, Douglas, QLD 4814, Australia.
| | - Hayley L Letson
- College of Medicine & Dentistry, Heart and Trauma Research Laboratory, James Cook University, 1 James Cook Drive, Townsville, QLD 4811, Australia.
| |
Collapse
|
11
|
Dobson GP, Morris JL, Letson HL. Immune dysfunction following severe trauma: A systems failure from the central nervous system to mitochondria. Front Med (Lausanne) 2022; 9:968453. [PMID: 36111108 PMCID: PMC9468749 DOI: 10.3389/fmed.2022.968453] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 08/01/2022] [Indexed: 12/20/2022] Open
Abstract
When a traumatic injury exceeds the body's internal tolerances, the innate immune and inflammatory systems are rapidly activated, and if not contained early, increase morbidity and mortality. Early deaths after hospital admission are mostly from central nervous system (CNS) trauma, hemorrhage and circulatory collapse (30%), and later deaths from hyperinflammation, immunosuppression, infection, sepsis, acute respiratory distress, and multiple organ failure (20%). The molecular drivers of secondary injury include damage associated molecular patterns (DAMPs), pathogen associated molecular patterns (PAMPs) and other immune-modifying agents that activate the hypothalamic-pituitary-adrenal (HPA) axis and sympathetic stress response. Despite a number of drugs targeting specific anti-inflammatory and immune pathways showing promise in animal models, the majority have failed to translate. Reasons for failure include difficulty to replicate the heterogeneity of humans, poorly designed trials, inappropriate use of specific pathogen-free (SPF) animals, ignoring sex-specific differences, and the flawed practice of single-nodal targeting. Systems interconnectedness is a major overlooked factor. We argue that if the CNS is protected early after major trauma and control of cardiovascular function is maintained, the endothelial-glycocalyx will be protected, sufficient oxygen will be delivered, mitochondrial energetics will be maintained, inflammation will be resolved and immune dysfunction will be minimized. The current challenge is to develop new systems-based drugs that target the CNS coupling of whole-body function.
Collapse
Affiliation(s)
- Geoffrey P. Dobson
- Heart and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, QLD, Australia
| | | | | |
Collapse
|
12
|
Morris JL, McEwen P, Letson HL, Dobson GP. Anterior Cruciate Ligament Reconstruction Surgery: Creating a Permissive Healing Phenotype in Military Personnel and Civilians for Faster Recovery. Mil Med 2022; 187:1310-1317. [PMID: 35389483 PMCID: PMC9617292 DOI: 10.1093/milmed/usac093] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 02/28/2022] [Accepted: 05/20/2022] [Indexed: 11/16/2022] Open
Abstract
Introduction Anterior cruciate ligament (ACL) rupture in military personnel and civilians can be a devastating injury. A service member is 10 times more likely to suffer an ACL injury than their civilian counterparts, and despite successful surgical stabilization, 4%-35% will develop arthrofibrosis, over 50% will not return to full active duty, and up to 50% will develop post-traumatic osteoarthritis (PTOA) within 15 years. Equally concerning, woman are 2 to 8 times more likely to experience ACL injuries than men, which represents a major knowledge gap. Materials and Methods A comprehensive literature search was performed in December 2021 using structured search terms related to prevalence, risk factors, disease progression, and treatment of ACL injury and reconstruction. The literature search was conducted independently by two researchers using PubMed, Cochrane, and Embase databases, with inclusion of articles with military, civilian, and sex relevance, and exclusion of most papers with a publication date greater than 10 years. The resources used for the review reflect the most current data, knowledge, and recommendations associated with research and clinical findings from reliable international sources. Results Currently, there is no effective system-based drug therapy that creates a “permissive environment” to reduce synovial and cartilage stress after ACL injury and reconstruction and prevent secondary complications. We argue that progress in this area has been hampered by researchers and clinicians failing to recognize that (1) an ACL injury is a system’s failure that affects the whole joint, (2) the early molecular events define and perpetuate different injury phenotypes, (3) male and female responses may be different and have a molecular basis, (4) the female phenotype continues to be under-represented in basic and clinical research, and (5) the variable outcomes may be perpetuated by the trauma of surgery itself. The early molecular events after ACL injury are characterized by an overexpression of joint inflammation, immune dysfunction, and trauma-induced synovial stress. We are developing an upstream adenosine, lidocaine, and magnesium therapy to blunt these early molecular events and expedite healing with less arthrofibrosis and early PTOA complications. Conclusions ACL injuries continue to be a major concern among military personnel and civilians and represent a significant loss in command readiness and quality of life. The lack of predictability in outcomes after ACL repair or reconstruction underscores the need for new joint protection therapies. The male–female disparity requires urgent investigation.
Collapse
Affiliation(s)
- Jodie L Morris
- Heart and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville 4811, Australia
| | - Peter McEwen
- The Orthopaedic Research Institute of Queensland (ORIQL), Townsville, Queensland, QLD 4812, Australia
| | - Hayley L Letson
- Heart and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville 4811, Australia
| | - Geoffrey P Dobson
- Heart and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville 4811, Australia
| |
Collapse
|
13
|
Letson HL, Morris JL, Biros E, Dobson GP. ALM Induces Cellular Quiescence in the Surgical Margin 3 d Following Liver Resection, Hemorrhage, and Shock. J Surg Res 2022; 275:16-28. [PMID: 35219247 DOI: 10.1016/j.jss.2022.01.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 01/24/2022] [Accepted: 01/25/2022] [Indexed: 11/30/2022]
Abstract
INTRODUCTION The liver has a remarkable capacity to regenerate but not the resected lobe. Our aim was to examine the expression of a number of key genes of metabolism, proliferation, survival, and reprogramming 5 mm inside the resected margin following resuscitation with adenosine, lidocaine, and Mg2+ (ALM) therapy. MATERIALS AND METHODS Anesthetized adult male Sprague-Dawley rats randomly assigned to ALM treatment (n = 10) or Saline controls (n = 10) underwent liver resection (60% left lateral lobe) and uncontrolled bleeding. After 15 min, 3% NaCl ± ALM bolus was administered, and after 60 min, a 4 h 0.9% NaCl ± ALM stabilization 'drip' was commenced. After 72 h monitoring (or high moribund score), histopathology, inflammatory mediators, and relative expression of key genes of tissue repair were measured in the remaining left lateral liver. RESULTS ALM animals survived 72 h compared to 23 h for Saline controls (P = 0.002). In the surgical margin, ALM therapy showed preservation of cellular architecture, whereas controls had increased inflammation and diffuse necrosis. Liver proinflammatory cytokines were also 2- to 4-fold higher in Saline controls. ALM therapy dramatically suppressed (∼70%) gene expression of four adenosine receptors, metabolic signaling, autophagy, apoptosis, and cell proliferation compared to controls, including suppression of the Yamanaka factors by up to 85%. CONCLUSIONS We conclude ALM therapy preserved hepatocyte architecture with less inflammation and necrosis 3 d after resection, hemorrhage, and shock. In addition, ALM induced cellular quiescence in the surgical margin, which may be a strategy for improved barrier protection and healing. Further studies are required to address this question.
Collapse
Affiliation(s)
- Hayley L Letson
- Heart and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, Australia
| | - Jodie L Morris
- Heart and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, Australia
| | - Erik Biros
- Heart and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, Australia
| | - Geoffrey P Dobson
- Heart and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, Australia.
| |
Collapse
|
14
|
Letson HL, Biros E, Morris JL, Dobson GP. ALM Fluid Therapy Shifts Sympathetic Hyperactivity to Parasympathetic Dominance in the Rat Model of Non-Compressible Hemorrhagic Shock. Shock 2022; 57:264-273. [PMID: 34798632 DOI: 10.1097/shk.0000000000001886] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
ABSTRACT Excessive sympathetic outflow following trauma can lead to cardiac dysfunction, inflammation, coagulopathy, and poor outcomes. We previously reported that buprenorphine analgesia decreased survival after hemorrhagic trauma. Our aim is to examine the underlying mechanisms of mortality in a non-compressible hemorrhage rat model resuscitated with saline or adenosine, lidocaine, magnesium (ALM). Anesthetized adult male Sprague-Dawley rats were randomly assigned to Saline control group or ALM therapy group (both n = 10). Hemorrhage was induced by 50% liver resection. After 15 min, 0.7 mL/kg 3% NaCl ± ALM intravenous bolus was administered, and after 60 min, 0.9% NaCl ± ALM was infused for 4 h (0.5 mL/kg/h) with 72 h monitoring. Animals received 6-12-hourly buprenorphine for analgesia. Hemodynamics, heart rate variability, echocardiography, and adiponectin were measured. Cardiac tissue was analyzed for adrenergic/cholinergic receptor expression, inflammation, and histopathology. Four ALM animals and one Saline control survived to 72 h. Mortality was associated with up to 97% decreases in adrenergic (β-1, α-1A) and cholinergic (M2) receptor expression, cardiac inflammation, myocyte Ca2+ loading, and histopathology, indicating heart ischemia/failure. ALM survivors had higher cardiac output and stroke volume, a 30-fold increase in parasympathetic/sympathetic receptor expression ratio, and higher circulating adiponectin compared to Saline controls. Paradoxically, Saline cardiac adiponectin hormone levels were higher than ALM, with no change in receptor expression, indicating intra-cardiac synthesis. Mortality appears to be a "systems failure" associated with CNS dysregulation of cardiac function. Survival involves an increased parasympathetic dominance to support cardiac pump function with reduced myocardial inflammation. Increased cardiac α-1A adrenergic receptor in ALM survivors may be significant, as this receptor is highly protective during heart dysfunction/failure.
Collapse
Affiliation(s)
- Hayley L Letson
- Heart and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, Queensland, Australia
| | | | | | | |
Collapse
|
15
|
Abstract
We all want to be right in our thinking. Vaccine hesitancy and global warming denial share much in common: (1) both are threats to personal, community and global health, (2) action is contingent on co-operation and social policy, and (3) public support relies on trust in science. The irony is, however, as the science has become more convincing, public opinion has become more divided. A number of early polls showed that ~70% of people supported COVID-19 vaccine use and global warming, ~20% adopted a wait-and-see approach, and ~10% were staunch objectors. Although these percentages are approximate, what factors are responsible for the differences in engagement, doubt and distrust? How can we reduce the consensus gap? One approach is to return to grass roots and provide a brief history of the issues, understand the difference between fact and opinion, truth and falsehood, the problem of certainty, and how scientific consensus is reached. To doubt is a healthy response to new information, and it too has a scientific basis. Doubt and distrust reside in that region of the brain called the dorsolateral prefrontal cortex, which is responsible for suppressing unwanted representations. Bridging the consensus gap requires shifting human thinking patterns from doubt to belief, and belief to action. Education and improved public messaging are key, and social media providers require urgent oversight or regulation to remove false and harmful/dangerous content from our digital lives. Delays to vaccinate and failure to reduce greenhouse gases will dramatically change the way we live. The new norm may be more deadly COVID variants, strained healthcare systems, extreme weather patterns, diminished food supply, delays in goods and services, damage to world's economies and widespread global instability.
Collapse
Affiliation(s)
- Geoffrey P. Dobson
- Heart and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, QLD, Australia
| |
Collapse
|
16
|
Morris JL, Letson HL, McEwen P, Biros E, Dlaska C, Hazratwala K, Wilkinson M, Dobson GP. Comparison of intra-articular administration of adenosine, lidocaine and magnesium solution and tranexamic acid for alleviating postoperative inflammation and joint fibrosis in an experimental model of knee arthroplasty. J Orthop Surg Res 2021; 16:726. [PMID: 34930351 PMCID: PMC8686251 DOI: 10.1186/s13018-021-02871-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Accepted: 12/05/2021] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Dysregulated inflammatory responses are implicated in the pathogenesis of joint stiffness and arthrofibrosis following total knee arthroplasty (TKA). The purpose of this study was to compare the effects of intra-articular (IA) administration of tranexamic acid (TXA), an anti-fibrinolytic commonly used in TKA, and ALM chondroprotective solution on postoperative inflammation and joint tissue healing in a rat model of knee implant surgery. METHODS Male Sprague-Dawley rats (n = 24) were randomly divided into TXA or ALM treatment groups. The right knee of each rat was implanted with titanium (femur) and polyethylene (tibia) implants. An IA bolus (0.1 ml) of TXA or ALM was administered after implantation and capsule closure, and before skin closure. Postoperative coagulopathy, haematology and systemic inflammatory changes were assessed. Inflammatory and fibrotic markers were assessed in joint tissue, 28 days after surgery. RESULTS Haemostasis was comparable in animals treated with TXA or ALM after knee implant surgery. In contrast to ALM-treated animals, systemic inflammatory markers remained elevated at day 5 (IL-6, IL-12, IL-10, platelet count) and day 28 (IL-1β, IL-10) following surgery in TXA-treated animals. At day 28 following surgery, the extension range of motion of operated knees was 1.7-fold higher for ALM-treated animals compared to the TXA group. Key inflammatory mediators (NF-κB, IL-12, IL-2), immune cell infiltration (CD68+ cells) and markers of fibrosis (α-SMA, TGF-β) were also lower in capsular tissue of ALM-treated knees at day 28. CONCLUSION Data suggest that IA administration of ALM is superior to TXA for reducing postoperative systemic and joint inflammation and promoting restoration of healthy joint tissue architecture in a rat model of TKA. Further studies are warranted to assess the clinical translational potential of ALM IA solution to improve patient outcomes following arthroplasty.
Collapse
Affiliation(s)
- Jodie L Morris
- Orthopaedic Research Institute of Queensland, Townsville, QLD, Australia.
- Heart and Trauma Research Laboratory, Division of Tropical Health and Medicine, College of Medicine and Dentistry,, James Cook University, Townsville, QLD, 4811, Australia.
| | - Hayley L Letson
- Heart and Trauma Research Laboratory, Division of Tropical Health and Medicine, College of Medicine and Dentistry,, James Cook University, Townsville, QLD, 4811, Australia
| | - Peter McEwen
- Orthopaedic Research Institute of Queensland, Townsville, QLD, Australia
| | - Erik Biros
- Heart and Trauma Research Laboratory, Division of Tropical Health and Medicine, College of Medicine and Dentistry,, James Cook University, Townsville, QLD, 4811, Australia
| | - Constantin Dlaska
- Orthopaedic Research Institute of Queensland, Townsville, QLD, Australia
| | - Kaushik Hazratwala
- Orthopaedic Research Institute of Queensland, Townsville, QLD, Australia
| | - Matthew Wilkinson
- Orthopaedic Research Institute of Queensland, Townsville, QLD, Australia
| | - Geoffrey P Dobson
- Heart and Trauma Research Laboratory, Division of Tropical Health and Medicine, College of Medicine and Dentistry,, James Cook University, Townsville, QLD, 4811, Australia
| |
Collapse
|
17
|
Letson HL, Dobson GP. The Role of Nitric Oxide in the Efficacy of Adenosine, Lidocaine, and Magnesium Treatment for Experimental Hemorrhagic Shock in Rats. Curr Ther Res Clin Exp 2021; 95:100655. [PMID: 34917219 PMCID: PMC8665347 DOI: 10.1016/j.curtheres.2021.100655] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 11/12/2021] [Indexed: 11/25/2022] Open
Abstract
Background Nitric oxide (NO) plays multiple roles regulating the central nervous, cardiovascular, and immune systems. Objective Our aim was to investigate the role of NO in the efficacy of hypertonic saline (7.5% sodium chloride [NaCl]) adenosine, lidocaine, and magnesium (ALM) to improve mean arterial pressure (MAP) and heart rate following hemorrhagic shock. Methods One hundred one male Sprague-Dawley rats (mean [SD] weight = 425 [6] g) were randomly assigned to 20 groups (groups of 4–8 rats each). Hemorrhagic shock (MAP < 40 mm Hg) was induced by 20-minute pressure-controlled bleeding (∼40% blood volume), and the animal was left in shock (MAP = 35-40 mm Hg) for 60 minutes. The NO synthase (NOS) inhibitor L-NAME was administered with a 0.3-mL bolus of different combinations of 7.5% NaCl ALM active ingredients and hemodynamic parameters were monitored for 60 minutes. A number of specific NOS and NO inhibitors were tested. Results We found that 7.5% NaCl ALM corrected MAP after hemorrhagic shock. In contrast, the addition of L-NAME to 7.5% NaCl ALM led to a rapid fall in MAP, sustained ventricular arrhythmias, and 100% mortality. Saline controls receiving 7.5% NaCl with NG-nitro-l-arginine methyl ester (L-NAME) showed improved MAP with no deaths. None of the specific NOS and NO inhibitors mimicked L-NAME's effect on ALM. The addition of inducible NOS inhibitor 1400W to 7.5% NaCl ALM failed to resuscitate, whereas the NO scavenger PTIO and the PI3K inhibitor wortmannin reduced MAP recovery during 60-minute resuscitation. Conclusions The ability of 7.5% NaCl ALM to resuscitate appears to be linked to 1 or more NO-producing pathways. Nonspecific NOS inhibition with L-NAME blocked ALM resuscitation and led to cardiovascular collapse. More studies are required to examine NO site-specific contributions to ALM resuscitation. (Curr Ther Res Clin Exp. 2022; 82:XXX–XXX)
Collapse
Affiliation(s)
- Hayley L Letson
- Heart, Trauma, and Sepsis Research Laboratory, College of Medicine & Dentistry, James Cook University, Townsville, Queensland, Australia
| | - Geoffrey P Dobson
- Heart, Trauma, and Sepsis Research Laboratory, College of Medicine & Dentistry, James Cook University, Townsville, Queensland, Australia
| |
Collapse
|
18
|
Dobson GP, Morris JL, Biros E, Davenport LM, Letson HL. Major surgery leads to a proinflammatory phenotype: Differential gene expression following a laparotomy. Ann Med Surg (Lond) 2021; 71:102970. [PMID: 34745602 PMCID: PMC8554464 DOI: 10.1016/j.amsu.2021.102970] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Accepted: 10/17/2021] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND The trauma of surgery is a neglected area of research. Our aim was to examine the differential expression of genes of stress, metabolism and inflammation in the major organs of a rat following a laparotomy. MATERIALS AND METHODS Anaesthetised Sprague-Dawley rats were randomised into baseline, 6-hr and 3-day groups (n = 6 each), catheterised and laparotomy performed. Animals were sacrificed at each timepoint and tissues collected for gene and protein analysis. Blood stress hormones, cytokines, endothelial injury markers and coagulation were measured. RESULTS Stress hormone corticosterone significantly increased and was accompanied by significant increases in inflammatory cytokines, endothelial markers, increased neutrophils (6-hr), higher lactate (3-days), and coagulopathy. In brain, there were significant increases in M1 muscarinic (31-fold) and α-1A-adrenergic (39-fold) receptor expression. Cortical expression of metabolic genes increased ∼3-fold, and IL-1β by 6-fold at 3-days. Cardiac β-1-adrenergic receptor expression increased up to 8.4-fold, and M2 and M1 muscarinic receptors by 2 to 4-fold (6-hr). At 3-days, cardiac mitochondrial gene expression (Tfam, Mtco3) and inflammation (IL-1α, IL-4, IL-6, MIP-1α, MCP-1) were significantly elevated. Haemodynamics remained stable. In liver, there was a dramatic suppression of adrenergic and muscarinic receptor expression (up to 90%) and increased inflammation. Gut also underwent autonomic suppression with 140-fold increase in IL-1β expression (3-days). CONCLUSIONS A single laparotomy led to a surgical-induced proinflammatory phenotype involving neuroendocrine stress, cortical excitability, immune activation, metabolic changes and coagulopathy. The pervasive nature of systemic and tissue inflammation was noteworthy. There is an urgent need for new therapies to prevent hyper-inflammation and restore homeostasis following major surgery.
Collapse
Affiliation(s)
- Geoffrey P. Dobson
- Heart and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, 4811, Australia
| | - Jodie L. Morris
- Heart and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, 4811, Australia
| | - Erik Biros
- Heart and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, 4811, Australia
| | - Lisa M. Davenport
- Heart and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, 4811, Australia
| | - Hayley L. Letson
- Heart and Trauma Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, 4811, Australia
| |
Collapse
|
19
|
Sharma C, Dobson GP, Davenport LM, Morris JL, Letson HL. The role of matrix metalloproteinase-9 and its inhibitor TIMP-1 in burn injury: a systematic review. Int J Burns Trauma 2021; 11:275-288. [PMID: 34557330 PMCID: PMC8449144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 06/25/2021] [Indexed: 06/13/2023]
Abstract
Matrix metalloproteinase-9 (MMP-9) and its endogenous inhibitor, tissue inhibitor of metalloproteinase-1 (TIMP-1), are key mediators of acute inflammation and regulators of the wound healing process. The aim of this systematic review was to determine the local and systemic involvement of the MMP-9/TIMP-1 system following burn injury. Two databases (Scopus and MEDLINE) were searched for all studies reporting MMP-9 and/or TIMP-1 after burn injury. Based on our eligibility criteria, we reviewed 24 studies involving 508 burns patients in 11 clinical studies and 367 animals in 13 preclinical studies. Local, systemic, and peripheral gene expression, protein levels and activity of MMP-9 and TIMP-1 were assessed. Increased MMP-9 was reported at the site of injury early after burn trauma in all studies, and remained elevated in non-healing wounds. Increased TIMP-1 expression in burn wounds occurred later than MMP-9, and was persistent in hypertrophic burn scars. Similar to local expression, systemic MMP-9 and TIMP-1 concentrations were significantly elevated after burn injury in response to upregulation of proinflammatory cytokines. While no association was found between systemic MMP-9 concentration and extent of injury or outcome, serum or plasma TIMP-1 showed good correlation with survival and burn severity. This review also found evidence of the MMP-9/TIMP-1 system contributing to secondary tissue damage distant from the burn site, including burn-associated musculoskeletal damage and acute lung injury. In addition, increased MMP-9 synthesis and activity in the brain after peripheral burn may lead to blood-brain barrier dysfunction and cerebral edema, a significant contributor to mortality. This systematic review provides an overview of the available evidence of the role of MMP-9 and TIMP-1 in burn injury pathophysiology and finds that TIMP-1 may be a promising biomarker in outcome prognostication of burns patients. Large-scale studies of both pediatric and adult burns patients with increased female representation and repeated sampling are recommended to validate the reliability of TIMP-1 as a prognostic marker following burn injury.
Collapse
Affiliation(s)
- Chinmay Sharma
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook UniversityQueensland 4811, Australia
| | - Geoffrey P Dobson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook UniversityQueensland 4811, Australia
| | - Lisa M Davenport
- Townsville University Hospital100 Angus Smith Drive, Douglas, Queensland 4814, Australia
| | - Jodie L Morris
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook UniversityQueensland 4811, Australia
| | - Hayley L Letson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook UniversityQueensland 4811, Australia
| |
Collapse
|
20
|
Dobson GP, Biros E, Letson HL, Morris JL. Living in a Hostile World: Inflammation, New Drug Development, and Coronavirus. Front Immunol 2021; 11:610131. [PMID: 33552070 PMCID: PMC7862725 DOI: 10.3389/fimmu.2020.610131] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 11/25/2020] [Indexed: 12/14/2022] Open
Abstract
We present a brief history of the immune response and show that Metchnikoff's theory of inflammation and phagocytotic defense was largely ignored in the 20th century. For decades, the immune response was believed to be triggered centrally, until Lafferty and Cunningham proposed the initiating signal came from the tissues. This shift opened the way for Janeway's pattern recognition receptor theory, and Matzinger's danger model. All models failed to appreciate that without inflammation, there can be no immune response. The situation changed in the 1990s when cytokine biology was rapidly advancing, and the immune system's role expanded from host defense, to the maintenance of host health. An inflammatory environment, produced by immune cells themselves, was now recognized as mandatory for their attack, removal and repair functions after an infection or injury. We explore the cellular programs of the immune response, and the role played by cytokines and other mediators to tailor the right response, at the right time. Normally, the immune response is robust, self-limiting and restorative. However, when the antigen load or trauma exceeds the body's internal tolerances, as witnessed in some COVID-19 patients, excessive inflammation can lead to increased sympathetic outflows, cardiac dysfunction, coagulopathy, endothelial and metabolic dysfunction, multiple organ failure and death. Currently, there are few drug therapies to reduce excessive inflammation and immune dysfunction. We have been developing an intravenous (IV) fluid therapy comprising adenosine, lidocaine and Mg2+ (ALM) that confers a survival advantage by preventing excessive inflammation initiated by sepsis, endotoxemia and sterile trauma. The multi-pronged protection appears to be unique and may provide a tool to examine the intersection points in the immune response to infection or injury, and possible ways to prevent secondary tissue damage, such as that reported in patients with COVID-19.
Collapse
Affiliation(s)
- Geoffrey P. Dobson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, QLD, Australia
| | | | | | | |
Collapse
|
21
|
Onorati F, Francica A, Dobson GP, Faggian G. Myocardial protection: the forgotten 'polarized' modality. Eur J Cardiothorac Surg 2021; 59:284. [PMID: 32728693 DOI: 10.1093/ejcts/ezaa218] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Accepted: 05/23/2020] [Indexed: 11/13/2022] Open
Affiliation(s)
- Francesco Onorati
- Division of Cardiac Surgery, University of Verona, Verona, Italy.,Heart, Trauma and Sepsis Research Laboratory, James Cook University, Townsville, QLD, Australia
| | - Alessandra Francica
- Division of Cardiac Surgery, University of Verona, Verona, Italy.,Heart, Trauma and Sepsis Research Laboratory, James Cook University, Townsville, QLD, Australia
| | - Geoffrey P Dobson
- Division of Cardiac Surgery, University of Verona, Verona, Italy.,Heart, Trauma and Sepsis Research Laboratory, James Cook University, Townsville, QLD, Australia
| | - Giuseppe Faggian
- Division of Cardiac Surgery, University of Verona, Verona, Italy.,Heart, Trauma and Sepsis Research Laboratory, James Cook University, Townsville, QLD, Australia
| |
Collapse
|
22
|
Engstrom N, Dobson GP, Ng K, Letson HL. Primary Prevention Implantable Cardiac Defibrillators: A Townsville District Perspective. Front Cardiovasc Med 2020; 7:577248. [PMID: 33195463 PMCID: PMC7652736 DOI: 10.3389/fcvm.2020.577248] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 09/14/2020] [Indexed: 12/07/2022] Open
Abstract
Background: Despite major advances in treating patients with severe heart failure, deciding who should receive an implantable cardiac defibrillator (ICD) remains challenging. Objective: To study the risk factors and mortality in patients after receiving an ICD (January 2008–December 2015) in a regional hospital in Australia. Methods: Eighty-two primary prevention patients received an ICD for ischemic cardiomyopathy (ICM, n = 41) and non-ischemic cardiomyopathy (NICM, n = 40) with 4.8-yrs follow-up. One patient had mixed ICM/NICM indications. Ventricular arrhythmias were assessed using intracardiac electrograms. Statistical analysis compared the total population and ICM and NICM groups using Kaplan-Meier for survival, Cox regression for mortality predictors, and binary logistic regression for predictors of ventricular arrhythmias (p < 0.05). Results: Major risk factors were hypercholesterolemia (70.7%), hypertension (47.6%), and obesity (41.5%). Severe obstructive sleep apnea (OSA) was found exclusively in NICM patients (23.7%, p = 0.001). Mortality was 30.5% after 4.8-yrs. The majority of patients (n=67) had no sustained ventricular arrhythmias yet 28% received therapy (n = 23), 18.51% were appropriate (n = 15), and 13.9% inappropriate (n = 11). Patients receiving ≥2 incidences of inappropriate shocks were 18-times more likely to die (p = 0.013). Three sudden cardiac deaths (SCD) (3.7%) were prevented by the ICD. Conclusion: Patients implanted with an ICD in Townsville had 30.5% all-cause mortality after 4.8-yrs. Only 28% of patients received ICD therapy and 13.9% were inappropriate. OSA may have contributed to the fourfold increase in inappropriate therapy in NICM patients. Our study raises important efficacy, ethical and healthcare cost questions about who should receive an ICD, and possible regional and urban center disparities.
Collapse
Affiliation(s)
- Nathan Engstrom
- College of Medicine & Dentistry, Heart, Trauma and Sepsis Research Laboratory, James Cook University, Townsville, QLD, Australia.,Cardiac Investigations, The Townsville University Hospital, Douglas, QLD, Australia
| | - Geoffrey P Dobson
- College of Medicine & Dentistry, Heart, Trauma and Sepsis Research Laboratory, James Cook University, Townsville, QLD, Australia
| | - Kevin Ng
- Cardiology Clinic, Cairns Hospital, Cairns, QLD, Australia
| | - Hayley L Letson
- College of Medicine & Dentistry, Heart, Trauma and Sepsis Research Laboratory, James Cook University, Townsville, QLD, Australia
| |
Collapse
|
23
|
Dobson GP, Letson HL. Far Forward Gaps in Hemorrhagic Shock and Prolonged Field Care: An Update of ALM Fluid Therapy for Field Use. J Spec Oper Med 2020; 20:128-134. [PMID: 32969018 DOI: 10.55460/06vt-9ih4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 09/01/2020] [Indexed: 11/09/2022]
Abstract
Future expeditionary missions are expected to occur in more remote austere environments where combat medics and casualties may have to wait up to 7 days before resupply or safe evacuation. Currently, there is no effective fluid therapy for hemorrhagic shock (HS) at the point-of-injury and continuum-of-care over this extended period. We have been developing a small-volume IV or IO ALM therapy for noncompressible HS and have shown in preclinical models that it extends survival to 3 days, reduces abdominal bleeding by 60%, blunts inflammation, corrects coagulopathy, preserves platelet function, and prevents immunodeficiency. The ALM-survival phenotype is associated with an upregulation of the master genes of metabolism and mitochrondrial biogenesis in heart and brain and a downregulation in the periphery. Future translational studies will investigate the timing and nature of the "switch" and extend survival to 7 days. We will also discuss some of the controversies of ALM resuscitation in pigs, present our Systems Hypothesis of Trauma (SHOT), and discuss future clinical safety trials before field use.
Collapse
|
24
|
Affiliation(s)
- Geoffrey P Dobson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, QLD, Australia
| |
Collapse
|
25
|
Abstract
Globally, a staggering 310 million major surgeries are performed each year; around 40 to 50 million in USA and 20 million in Europe. It is estimated that 1–4% of these patients will die, up to 15% will have serious postoperative morbidity, and 5–15% will be readmitted within 30 days. An annual global mortality of around 8 million patients places major surgery comparable with the leading causes of death from cardiovascular disease and stroke, cancer and injury. If surgical complications were classified as a pandemic, like HIV/AIDS or coronavirus (COVID-19), developed countries would work together and devise an immediate action plan and allocate resources to address it. Seeking to reduce preventable deaths and post-surgical complications would save billions of dollars in healthcare costs. Part of the global problem resides in differences in institutional practice patterns in high- and low-income countries, and part from a lack of effective perioperative drug therapies to protect the patient from surgical stress. We briefly review the history of surgical stress and provide a path forward from a systems-based approach. Key to progress is recognizing that the anesthetized brain is still physiologically ‘awake’ and responsive to the sterile stressors of surgery. New intravenous drug therapies are urgently required after anesthesia and before the first incision to prevent the brain from switching to sympathetic overdrive and activating secondary injury progression such as hyperinflammation, coagulopathy, immune activation and metabolic dysfunction. A systems-based approach targeting central nervous system-mitochondrial coupling may help drive research to improve outcomes following major surgery in civilian and military medicine.
Collapse
Affiliation(s)
- Geoffrey P Dobson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Queensland, 4811, Australia.
| |
Collapse
|
26
|
Letson HL, Granfeldt A, Jensen TH, Mattson TH, Dobson GP. Adenosine, Lidocaine, and Magnesium Support a High Flow, Hypotensive, Vasodilatory State With Improved Oxygen Delivery and Cerebral Protection in a Pig Model of Noncompressible Hemorrhage. J Surg Res 2020; 253:127-138. [PMID: 32353638 DOI: 10.1016/j.jss.2020.03.048] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 02/20/2020] [Accepted: 03/24/2020] [Indexed: 11/24/2022]
Abstract
BACKGROUND Noncompressible hemorrhage is the leading cause of preventable death in military and civilian trauma. Our aim was to examine the effect of adenosine, lidocaine, and magnesium (Mg2+; ALM) on cardiovascular and cerebral function in a porcine hepatic hemorrhage model. MATERIALS AND METHODS Pigs (59.1 ± 0.34 kg) were anesthetized, instrumented, and randomly assigned into sham (n = 6), saline controls (n = 10) or ALM (n = 10) groups before laparoscopic liver resection. After 30 min, groups received 4 mL/kg 3% NaCl ± ALM bolus (Phase 1) followed 60 min later with 3 mL/kg/h 0.9% NaCl ± ALM drip (4 h; Phase 2), then transfusion. Hemodynamics, carotid artery flow, and intracranial pressure were measured continuously. Microdialysis samples were analyzed for metabolites. RESULTS Saline controls had 20% mortality (mean survival time: 307 ± 38 min) with no ALM deaths over 6 h. Bolus administration increased mean arterial pressure (MAP) in both groups, and drip led to further increases to 62 ± 10 mmHg in controls compared with a steady fall to 47 ± 8 mmHg in ALM group at 240 min. The lower MAP was associated with a dramatic fall in systemic vascular resistance and improved oxygen delivery. ALM drip significantly increased cardiac output and stroke volume with lower dP/dtMin, indicating a less stiff heart. ALM drip also significantly decreased cerebral perfusion pressure, reduced cerebral oxygen consumption (28%), and reduced brain glycerol (60%), lactate (47%), and relative expression of hypoxia-inducible factor (38%) compared with saline controls. CONCLUSIONS ALM therapy improved cardiac function and oxygen delivery by lowering systemic vascular resistance after noncompressible hemorrhage. ALM also appeared to protect the brain at hypotensive MAPs with significantly lower cerebral perfusion pressure, lower O2 consumption, and significantly lower cortical lactate and glycerol levels compared to saline controls.
Collapse
Affiliation(s)
- Hayley L Letson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine & Dentistry, James Cook University, Townsville, Queensland, Australia
| | | | | | | | - Geoffrey P Dobson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine & Dentistry, James Cook University, Townsville, Queensland, Australia.
| |
Collapse
|
27
|
Dobson GP, Morris JL, Davenport LM, Letson HL. Traumatic-Induced Coagulopathy as a Systems Failure: A New Window into Hemostasis. Semin Thromb Hemost 2020; 46:199-214. [DOI: 10.1055/s-0039-1701018] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
AbstractTraumatic-induced coagulopathy (TIC) is often associated with significant bleeding, transfusion requirements, inflammation, morbidity, and mortality. This review considers TIC as a systems failure, not as a single-event manifestation of trauma. After briefly reviewing the meaning of TIC and the bewildering array of fibrinolysis phenotypes, we will discuss the role of platelets and fibrinogen in coagulopathy. Next, we will review the different TIC hypotheses and drill down to a single mechanistic domain comprising (1) thrombin's differential binding to thrombomodulin, (2) the expression of annexin II-S100A10 complex, and (3) the functional integrity of the endothelial glycocalyx. This triad forms the basis of the “switch” hypothesis of TIC. We will next address the potential limitations of current practice in treating a coagulation or fibrinolytic defect, and the next defect, and so on down the line, which often leads to what U.S. surgeon William C. Shoemaker considered “an uncoordinated and sometimes contradictory therapeutic outcome.” The treat-as-you-go approach using sequential, single-target treatments appears to be a by-product of decades of highly reductionist thinking and research. Lastly, we will present a unified systems hypothesis of TIC involving three pillars of physiology: the central nervous system (CNS)–cardiovascular system, the endothelial glycocalyx, and mitochondrial integrity. If CNS control of ventriculoarterial coupling is maintained close to unity following trauma, we hypothesize that the endothelium will be protected, mitochondrial energetics will be maintained, and TIC (and inflammation) will be minimized. The Systems Hypothesis of Trauma (SHOT) also helps to answer why certain groups of severely bleeding trauma patients are still dying despite receiving the best care. Currently, no drug therapy exists that targets the whole system.
Collapse
Affiliation(s)
- Geoffrey P. Dobson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, Queensland, Australia
| | - Jodie L. Morris
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, Queensland, Australia
| | - Lisa M. Davenport
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, Queensland, Australia
| | - Hayley L. Letson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, Queensland, Australia
| |
Collapse
|
28
|
Letson HL, Morris J, Biros E, Dobson GP. Conventional and Specific-Pathogen Free Rats Respond Differently to Anesthesia and Surgical Trauma. Sci Rep 2019; 9:9399. [PMID: 31253875 PMCID: PMC6599031 DOI: 10.1038/s41598-019-45871-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 06/12/2019] [Indexed: 02/08/2023] Open
Abstract
Specific-pathogen free (SPF) animals were introduced in the 1960s to minimize disease and infection as variables in biomedical research. Our aim was to examine differences in physiological response in rat colonies bred and housed in a conventional versus SPF facility, and implications for research. Sprague-Dawley rats were anesthetized and catheterized for blood and pressure monitoring, and electrocardiogram (ECG) leads implanted. Hematology was assessed, and coagulation profile using rotational thromboelastometry. Health screening was outsourced to Cerberus Sciences. SPF rats had significantly lower pulse pressure (38% decrease), arrhythmias and prolonged QTc (27% increase) compared to conventional rats. No arrhythmias were found in conventional rats. SPF rats had significantly higher white cell, monocyte, neutrophil and lymphocyte counts, and were hyperfibrinolytic, indicated by EXTEM maximum lysis >15%. Independent assessment revealed similar pathogen exclusion between colonies, with the exception of Proteus in SPF animals. Returning to a conventional facility restored normal host physiology. We conclude that SPF animals displayed an abnormal hemodynamic, hematological and hemostatic phenotype in response to anesthesia and surgery, and provide a number of recommendations to help standardize research outcomes and translation.
Collapse
Affiliation(s)
- Hayley L Letson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Queensland, 4811, Australia
| | - Jodie Morris
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Queensland, 4811, Australia
| | - Erik Biros
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Queensland, 4811, Australia
| | - Geoffrey P Dobson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Queensland, 4811, Australia.
| |
Collapse
|
29
|
Davenport LM, Dobson GP, Letson HL. The role of invasive monitoring in the resuscitation of major burns: a systematic review and meta-analysis. Int J Burns Trauma 2019; 9:28-40. [PMID: 31149390 PMCID: PMC6526380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 04/07/2019] [Accepted: 04/11/2019] [Indexed: 06/09/2023]
Abstract
Increasingly, in major hospitals invasive monitoring endpoints are utilised to guide the acute resuscitation of burns. The aim of this review is to evaluate effects of invasive monitoring for major burns patients (>20% total body surface area) to prevent early organ dysfunction. Five databases were searched for randomised controlled trials and cohort studies that evaluated invasive monitoring within the acute phase (first 24 hours). Invasive monitoring included transesophageal echocardiogram, central venous pressure measurement, and pulmonary artery catheterisation. Primary outcomes included multiple organ failure scores, renal and cardiac dysfunction measurements, compartment syndrome and lactate at 24 hours. Secondary outcomes included mortality and intensive care unit stay. Ten studies involving 401 major burns patients were included. Data pooled from four studies demonstrated significantly improved cardiac index at 24 hours compared to non-invasive endpoints (MD: 0.65, 95% CI: 0.46-0.82, P=0.00001). Five studies pooled showed significantly increased urine output with invasive monitoring (MD: 0.18, 95% CI: 0.03-0.34, P=0.02), whereas there was no difference in blood lactate levels (MD: -0.11, 95% CI: -0.44-0.22, P=0.43). There was a trend for lower mortality in invasive monitoring groups compared with non-invasive controls; however, the difference was not significant. There remains insufficient evidence to determine whether invasive monitoring to guide fluid resuscitation improves patient outcomes after major burn trauma. Although meta-analysis determined significantly improved cardiac index and urine output, further studies are required.
Collapse
Affiliation(s)
- Lisa M Davenport
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University Queensland 4811, Australia
| | - Geoffrey P Dobson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University Queensland 4811, Australia
| | - Hayley L Letson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University Queensland 4811, Australia
| |
Collapse
|
30
|
McCutchan A, Dobson GP, Stewart N, Letson HL, Grant AL, Jovanovic IA, Hazratwala K, Wilkinson M, McEwen P, Morris J. Absence of cytotoxic and inflammatory effects following in vitro exposure of chondrogenically-differentiated human mesenchymal stem cells to adenosine, lidocaine and Mg 2+ solution. J Exp Orthop 2019; 6:16. [PMID: 30989345 PMCID: PMC6465392 DOI: 10.1186/s40634-019-0185-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 03/22/2019] [Indexed: 12/12/2022] Open
Abstract
Background ALM solution, a combination of adenosine, lidocaine and Mg2+, is an emerging small volume therapy that has been shown to prevent and correct coagulopathy and surgery-related inflammation in preclinical models, though its application in orthopaedic surgery is yet to be demonstrated. The effect of ALM solution on chondrocytes is unknown. The aim of this preliminary study was to investigate the effect of ALM solution on viability and inflammatory responses of chondrogenically-differentiated human bone marrow-derived mesenchymal stem cells (chondro-MSC), in vitro. Methods Chondro-MSC were exposed to media only, saline (0.9% NaCl or 1.3% NaCl) only, or saline containing ALM (1 mM adenosine, 3 mM lidocaine, 2.5 mM Mg2+) or tranexamic acid (TXA, 100 mg/ml) for 1 or 4 h. Responses to ALM solutions containing higher lidocaine concentrations were also compared. Chondrocyte viability was determined using WST-8 colorimetric assays and inflammatory cytokine (TNF-α, IL-1β, IL-8) and matrix metalloproteinases (MMP-3, MMP-12, MMP-13) concentrations using multiplex bead arrays. Results The viability of chondro-MSC was significantly greater after 1 h treatment with ALM compared to saline (96.2 ± 7.9 versus 75.6 ± 7.3%). Extension of exposure times to 4 h had no significant adverse effect on cell viability after treatment with ALM (1 h, 85.4 ± 5.6 v 4 h, 74.0 ± 15.2%). Cytotoxicity was evident following exposure to solutions containing lidocaine concentrations greater than 30 mM. There were no significant differences in viability (80 ± 5.4 v 57.3 ± 16.2%) or secretion of IL-8 (60 ± 20 v 160 ± 50 pg/ml), MMP-3 (0.95 ± 0.6 v 3.4 ± 1.6 ng/ml), and MMP-13 (4.2 ± 2.4 v 9.2 ± 4.3 ng/ml) in chondro-MSC exposed to saline, ALM or TXA. Conclusions Short-term, in vitro exposure to clinically-relevant concentrations of ALM solution had no adverse inflammatory or chondrotoxic effects on human chondro-MSC, with responses comparable to saline and TXA. These findings provide support for continued evaluation of ALM solution as a possible therapeutic to improve outcomes following orthopaedic procedures.
Collapse
Affiliation(s)
- Andrew McCutchan
- Department of Haematology and Bone Marrow Transplantation, Townsville Hospital, Townsville, Australia
| | - Geoffrey P Dobson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, Australia
| | - Natalie Stewart
- Department of Haematology and Bone Marrow Transplantation, Townsville Hospital, Townsville, Australia
| | - Hayley L Letson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, Australia
| | - Andrea L Grant
- The Orthopaedic Research Institute of Queensland, 7 Turner St, Pimlico, Townsville, Q 4812, Australia
| | | | - Kaushik Hazratwala
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, Australia.,The Orthopaedic Research Institute of Queensland, 7 Turner St, Pimlico, Townsville, Q 4812, Australia
| | - Matthew Wilkinson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, Australia.,The Orthopaedic Research Institute of Queensland, 7 Turner St, Pimlico, Townsville, Q 4812, Australia
| | - Peter McEwen
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, Australia.,The Orthopaedic Research Institute of Queensland, 7 Turner St, Pimlico, Townsville, Q 4812, Australia
| | - Jodie Morris
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, Australia. .,The Orthopaedic Research Institute of Queensland, 7 Turner St, Pimlico, Townsville, Q 4812, Australia.
| |
Collapse
|
31
|
Morris JL, Letson HL, Gillman R, Hazratwala K, Wilkinson M, McEwen P, Dobson GP. The CNS theory of osteoarthritis: Opportunities beyond the joint. Semin Arthritis Rheum 2019; 49:331-336. [PMID: 30982553 DOI: 10.1016/j.semarthrit.2019.03.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 03/02/2019] [Accepted: 03/14/2019] [Indexed: 01/06/2023]
Abstract
Osteoarthritis (OA) is a leading cause of global disability that affects more than half of the population over 65. It is not a single disease but a progressive, inflammatory- and immune-altering multi-disease that affects the whole joint. OA has many risk factors including age, obesity, gender, lifestyle, joint morphology, metabolic dysfunction and genetic disposition. A major stumbling block in treating clinical OA has been the inability to detect its early onset and disease progression. This gap in understanding may arise from our failure to recognize that the OA patient exhibits a vulnerability to dysregulation of central feedback circuits that control sympathetic tone, inflammation, circadian rhythms (central and peripheral clocks), gut microbiome, metabolic redox and whole joint pathology. Early detection of OA and slowing its progression may come from discoveries outside the joint targeting these potentially modifiable upstream targets. We argue that future treatments may benefit from moving from a knee-centric viewpoint to a more systems-based, whole-body approach. The challenge, however, will be to better characterize these key circuits and apply this knowledge to develop new therapies and interventions.
Collapse
Affiliation(s)
- Jodie L Morris
- The Orthopaedic Research Institute of Queensland (ORIQL), Townsville 4812, Queensland, Australia; Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, 1 James Cook Drive, 4811, Queensland, Australia.
| | - Hayley L Letson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, 1 James Cook Drive, 4811, Queensland, Australia.
| | - Rhys Gillman
- The Orthopaedic Research Institute of Queensland (ORIQL), Townsville 4812, Queensland, Australia.
| | - Kaushik Hazratwala
- The Orthopaedic Research Institute of Queensland (ORIQL), Townsville 4812, Queensland, Australia.
| | - Matthew Wilkinson
- The Orthopaedic Research Institute of Queensland (ORIQL), Townsville 4812, Queensland, Australia.
| | - Peter McEwen
- The Orthopaedic Research Institute of Queensland (ORIQL), Townsville 4812, Queensland, Australia
| | - Geoffrey P Dobson
- The Orthopaedic Research Institute of Queensland (ORIQL), Townsville 4812, Queensland, Australia; Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, 1 James Cook Drive, 4811, Queensland, Australia.
| |
Collapse
|
32
|
Dobson GP, Letson HL, Biros E, Morris J. Specific pathogen-free (SPF) animal status as a variable in biomedical research: Have we come full circle? EBioMedicine 2019; 41:42-43. [PMID: 30803932 PMCID: PMC6443024 DOI: 10.1016/j.ebiom.2019.02.038] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 02/18/2019] [Indexed: 02/07/2023] Open
Affiliation(s)
- Geoffrey P Dobson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Queensland 4811, Australia.
| | - Hayley L Letson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Queensland 4811, Australia.
| | - Erik Biros
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Queensland 4811, Australia.
| | - Jodie Morris
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Queensland 4811, Australia; The Orthopaedic Research Institute of Queensland (ORIQL), Townsville, Queensland 4812, Australia.
| |
Collapse
|
33
|
Dobson GP, Letson HL, Grant A, McEwen P, Hazratwala K, Wilkinson M, Morris JL. Defining the osteoarthritis patient: back to the future. Osteoarthritis Cartilage 2018; 26:1003-1007. [PMID: 29775734 DOI: 10.1016/j.joca.2018.04.018] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 03/30/2018] [Accepted: 04/09/2018] [Indexed: 02/08/2023]
Abstract
The history of osteoarthritis (OA) is important because it can help broaden our perspective on past and present controversies. The naming of OA, beginning with Heberden's nodes, is itself a fascinating story. According to Albert Hoffa, R. Llewellyn Jones and Archibald Edward Garrod, the name OA was introduced in the mid-nineteenth century by surgeon Richard von Volkmann who distinguished it from rheumatoid arthritis and gout. Others preferred the terms 'chronical rheumatism', 'senile arthritis', 'hypertrophic arthritis' or 'arthritis deformans'. A similar narrative applies to the concept of OA affecting the whole joint vs the 'wear-and-tear' hypothesis, inflammation and the role of the central nervous system (CNS). In the late nineteenth and early twentieth centuries, the Garrods (father and son) and Hermann Senator argued that OA was a whole joint disease, and that inflammation played a major role in its progression. Garrod Jnr and John Spender also linked OA to a neurogenic lesion 'outside the joint'. The remaining twentieth century was no less dynamic, with major advances in basic science, diagnostics, treatments, surgical interventions and technologies. Today, OA is characterized as a multi-disease with inflammation, immune and CNS dysfunction playing central roles in whole joint damage, injury progression, pain and disability. In the current 'omics' era (genomics, proteomics and metabolomics), we owe a great debt to past physicians and surgeons who dared to think 'outside-the-box' to explain and treat OA. Over 130 years later, despite these developments, we still don't fully understand the underlying complexities of OA, and we still don't have a cure.
Collapse
Affiliation(s)
- G P Dobson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, 1 James Cook Drive, James Cook University, Queensland, 4811, Australia.
| | - H L Letson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, 1 James Cook Drive, James Cook University, Queensland, 4811, Australia.
| | - A Grant
- The Orthopaedic Research Institute of Queensland (ORIQL), Mater Hospital, Pimlico, Townsville, Queensland, 4812, Australia; Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, 1 James Cook Drive, James Cook University, Queensland, 4811, Australia.
| | - P McEwen
- The Orthopaedic Research Institute of Queensland (ORIQL), Mater Hospital, Pimlico, Townsville, Queensland, 4812, Australia.
| | - K Hazratwala
- The Orthopaedic Research Institute of Queensland (ORIQL), Mater Hospital, Pimlico, Townsville, Queensland, 4812, Australia.
| | - M Wilkinson
- The Orthopaedic Research Institute of Queensland (ORIQL), Mater Hospital, Pimlico, Townsville, Queensland, 4812, Australia.
| | - J L Morris
- The Orthopaedic Research Institute of Queensland (ORIQL), Mater Hospital, Pimlico, Townsville, Queensland, 4812, Australia; Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, 1 James Cook Drive, James Cook University, Queensland, 4811, Australia.
| |
Collapse
|
34
|
Grant AL, Letson HL, Morris JL, McEwen P, Hazratwala K, Wilkinson M, Dobson GP. Tranexamic acid is associated with selective increase in inflammatory markers following total knee arthroplasty (TKA): a pilot study. J Orthop Surg Res 2018; 13:149. [PMID: 29914535 PMCID: PMC6006687 DOI: 10.1186/s13018-018-0855-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 06/05/2018] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Tranexamic acid (TXA) is commonly used in orthopedic surgery to reduce excessive bleeding and transfusion requirements. Our aim was to examine if TXA was required in all osteoarthritis patients undergoing TKA surgery, and its possible effects on systemic inflammation and coagulation properties. METHODS Twenty-three patients (Oxford Score 22-29) were recruited consecutively; 12 patients received TXA before (IV, 1.2 g/90 kg) and immediately after surgery (intra-articular, 1.4 g/90 kg). Inflammatory mediators and ROTEM parameters were measured in blood at baseline, after the first bone-cut, immediately after surgery, and postoperative days 1 and 2. RESULTS After the bone cut and surgery, TXA significantly increased MCP-1, TNF-α, IL-1β and IL-6 levels compared to non-TXA patients, which was further amplified postoperatively. During surgery, TXA significantly prolonged EXTEM clot times, indicating a thrombin-slowing effect, despite little or no change in clot amplitude or fibrinogen. TXA was associated with three- to fivefold increases in FIBTEM maximum lysis (ML), a finding counter to TXA's antifibrinolytic effect. Maximum lysis for extrinsic and intrinsic pathways was < 8%, indicating little or no hyperfibrinolysis. No significant differences were found in postoperative hemoglobin between the two groups. CONCLUSIONS TXA was associated with increased systemic inflammation during surgery compared to non-TXA patients, with further amplification on postoperative days 1 and 2. On the basis of little or no change in viscoelastic clot strength, fibrinogen or clot lysis, there appeared to be no clinical justification for TXA in our group of patients. Larger prospective, randomized trials are required to investigate a possible proinflammatory effect in TKA patients.
Collapse
Affiliation(s)
- Andrea L Grant
- The Orthopaedic Research Institute of Queensland (ORIQL), 7 Turner St, Pimlico, Townsville, Queensland, 4812, Australia.,Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, 1 James Cook Drive, Townsville, Queensland, 4811, Australia
| | - Hayley L Letson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, 1 James Cook Drive, Townsville, Queensland, 4811, Australia
| | - Jodie L Morris
- The Orthopaedic Research Institute of Queensland (ORIQL), 7 Turner St, Pimlico, Townsville, Queensland, 4812, Australia.,Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, 1 James Cook Drive, Townsville, Queensland, 4811, Australia
| | - Peter McEwen
- The Orthopaedic Research Institute of Queensland (ORIQL), 7 Turner St, Pimlico, Townsville, Queensland, 4812, Australia.,Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, 1 James Cook Drive, Townsville, Queensland, 4811, Australia
| | - Kaushik Hazratwala
- The Orthopaedic Research Institute of Queensland (ORIQL), 7 Turner St, Pimlico, Townsville, Queensland, 4812, Australia.,Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, 1 James Cook Drive, Townsville, Queensland, 4811, Australia
| | - Matthew Wilkinson
- The Orthopaedic Research Institute of Queensland (ORIQL), 7 Turner St, Pimlico, Townsville, Queensland, 4812, Australia.,Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, 1 James Cook Drive, Townsville, Queensland, 4811, Australia
| | - Geoffrey P Dobson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, 1 James Cook Drive, Townsville, Queensland, 4811, Australia.
| |
Collapse
|
35
|
Arsyad A, Sokoya E, Dobson GP. Adenosine and lidocaine (AL) combination dilates intimally damaged rat thoracic aortic rings and guinea pig mesenteric arteries: possible significance to cardiac surgery. Am J Transl Res 2018; 10:1841-1851. [PMID: 30018724 PMCID: PMC6038079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2017] [Accepted: 05/05/2017] [Indexed: 06/08/2023]
Abstract
New pharmacotherapies are required to improve vessel graft protection and prevent vasoconstriction and spasm in CABG surgery. Previously we have studied adenosine (A) and lidocaine (L) relaxation in rat aortic rings, and reported a possible crosstalk between L relaxation and adenosine A2a receptor inhibition. The aim of the present study was to examine the effect of AL combination compared to A and L alone on relaxation in intact and denuded rat aortic rings and in guinea-pig pressurized mesenteric arterial segments. Aortic rings were harvested from Sprague-Dawley rats and equilibrated in an organ bath containing modified Krebs-Henseleit (KH) solution, pH 7.4, 37°C. Rings were pre-contracted sub-maximally with 0.3 µM norepinephrine, and the effects of increasing AL, A or L (up to 1.0 mM) were examined in intact and denuded rings. Mesenteric artery segments were isolated from guinea-pigs and mounted in an arteriograph containing KH solution and pressurised to 60 mmHg. Arteries were preconstricted with 10-8 M vasopressin and AL, A, or L was administered luminally or abluminally. Diameters were measured using video-microscopy. We report in intact rat aortic rings, AL increased relaxation from 21 to 100% (0.1-1.0 mM) and relaxation was endothelium-independent. Adenosine alone was also a potent relaxant of aortic rings but, unlike AL relaxation, it was partially endothelium-dependent. In intact mesenteric artery segments, increasing luminal AL produced a potent endothelium-independent dilation (up to 90%). Adenosine dilation was endothelium-independent but not lidocaine, which produced 33% dilation only after endothelial removal. Extra-luminal AL and A led to 76% and 80% dilationin intact segments respectively, whereas L resulted in constriction (10-17%). In conclusion, we show that AL can dilate aortic rings and mesenteric artery segments by up to 90% regardless of whether the endothelium is intact. We discuss the potential translational significance of AL to improve conduit protection in cardiac surgery, and other major surgeries.
Collapse
Affiliation(s)
- Aryadi Arsyad
- Department of Physiology, Medical Faculty, Hasanuddin UniversityJl. Perintis Kemerdekaan, Km. 10, Tamalanrea Makassar 90213, Indonesia
| | - Elke Sokoya
- Department of Human Physiology, School of Medicine, Flinders UniversityGPO Box 2100, Adelaide, SA 5001, Australia
| | - Geoffrey P Dobson
- Heart, Trauma and Sepsis Research Laboratory, Australian Institute of Tropical Health and Medicine, College of Medicine and Dentistry, 1 James Cook Drive, James Cook UniversityQueensland 4811, Australia
| |
Collapse
|
36
|
Abstract
BACKGROUND Currently, no drug therapy prevents secondary injury progression after traumatic brain injury (TBI). Our aim was to investigate the effects of small-volume intravenous adenosine, lidocaine, and Mg (ALM) resuscitation fluid after moderate TBI in a rat fluid-percussion injury model. METHODS Anesthetized, mechanically ventilated male Sprague-Dawley rats (449 ± 5 g) were randomly assigned to one of four groups: (1) sham (craniotomy without TBI), (2) no-treatment, (3) saline-control, or (4) ALM therapy groups (all n = 16). A subdural probe was implanted in eight animals per group to measure cerebral blood flow. Fifteen minutes after moderate TBI was induced with lateral fluid percussion injury (2.57 atm), a single 3% NaCl ± ALM bolus (0.7 mL/kg) was injected intravenously, and after 60 minutes (Phase 1), 0.9% NaCl ± ALM stabilization "drip" (0.5 mL/kg per hour) was administered for 3 hours (Phase 2). RESULTS Mortality (without subdural brain probe) was 25% (saline controls) and 0% (ALM). Sixty minutes after bolus, ALM significantly increased cardiac function, cortical blood flow (CBF; approximately threefold) and blunted systemic inflammation compared to saline controls. Three hours after infusion drip, ALM improved left ventricular function, supported higher CBF, decreased proinflammatory cytokines systemically (IL-1β, tumor necrosis factor α, and regulated on activation, normal T cell expressed and secreted [RANTES]), increased anti-inflammatory cytokines in brain tissue (IL-10, IL-4), lowered brain injury markers (neuron-specific enolase, Syndecan-1, HMGB-1), reduced coagulopathy, increased platelet aggregation, and maintained baseline fibrinogen levels. Saline-controls were proinflammatory (brain, heart, lung, and blood) and hypocoagulable with neurogenic enlargement of the right side of the heart. Survival time significantly correlated with plasma neuron-specific enolase (p = 0.001) and CBF at 180 minutes (p = 0.009), and CBF correlated with brain anti-inflammatory cytokines (p = 0.001-0.034). CONCLUSION After moderate TBI, ALM resuscitation fluid increased survival and protected against early secondary injury by reducing coagulopathy, inflammation, and platelet dysfunction.
Collapse
Affiliation(s)
- Hayley L Letson
- From the Heart, Trauma and Sepsis Research Laboratory (H.LL, G.P.D.), College of Medicine and Dentistry. James Cook University, Townsville, Queensland, Australia
| | | |
Collapse
|
37
|
Dobson GP, Doma K, Letson HL. Clinical relevance of a p value: Does tranexamic acid save lives after trauma or postpartum hemorrhage? J Trauma Acute Care Surg 2018; 84:532-536. [DOI: 10.1097/ta.0000000000001779] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
|
38
|
Dobson GP, Arsyad A, Letson HL. The Adenosine Hypothesis Revisited: Modulation of Coupling between Myocardial Perfusion and Arterial Compliance. Front Physiol 2017; 8:824. [PMID: 29104545 PMCID: PMC5654924 DOI: 10.3389/fphys.2017.00824] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Accepted: 10/06/2017] [Indexed: 12/25/2022] Open
Abstract
For over four decades the thoracic aortic ring model has become one of the most widely used methods to study vascular reactivity and electromechanical coupling. A question that is rarely asked, however, is what function does a drug-mediated relaxation (or contraction) in this model serve in the intact system? The physiological significance of adenosine relaxation in rings isolated from large elastic conduit arteries from a wide range of species remains largely unknown. We propose that adenosine relaxation increases aortic compliance in acute stress states and facilitates ventricular-arterial (VA) coupling, and thereby links compliance and coronary artery perfusion to myocardial energy metabolism. In 1963 Berne argued that adenosine acts as a local negative feedback regulator between oxygen supply and demand in the heart during hypoxic/ischemic stress. The adenosine VA coupling hypothesis extends and enhances Berne's "adenosine hypothesis" from a local regulatory scheme in the heart to include conduit arterial function. In multicellular organisms, evolution may have selected adenosine, nitric oxide, and other vascular mediators, to modulate VA coupling for optimal transfer of oxygen (and nutrients) from the lung, heart, large conduit arteries, arterioles and capillaries to respiring mitochondria. Finally, a discussion of the potential clinical significance of adenosine modulation of VA coupling is extended to vascular aging and disease, including hypertension, diabetes, obesity, coronary artery disease and heart failure.
Collapse
Affiliation(s)
- Geoffrey P Dobson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, QLD, Australia
| | - Aryadi Arsyad
- Physiology Department, Medical Faculty, Hasanuddin University, Makassar, Indonesia
| | - Hayley L Letson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville, QLD, Australia
| |
Collapse
|
39
|
Affiliation(s)
- Hayley L Letson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville City, QLD 4811, Australia
| | - Geoffrey P Dobson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Townsville City, QLD 4811, Australia.
| |
Collapse
|
40
|
Davenport L, Letson HL, Dobson GP. Immune-inflammatory activation after a single laparotomy in a rat model: effect of adenosine, lidocaine and Mg2+ infusion to dampen the stress response. Innate Immun 2017; 23:482-494. [DOI: 10.1177/1753425917718921] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Our aim was to examine the effect of low-volume 0.9% NaCl adenosine, lidocaine and Mg2+ (ALM) ‘drip’ on early immune-inflammatory activation after a single laparotomy with no further manipulation. Male Sprague–Dawley rats were anesthetized and randomly assigned to one of the groups, baseline, 1 h infusion 0.9% NaCl ± ALM and metrics, 1 h infusion and 6-h metrics, and 6 h continuous infusion and metrics. Complete blood count, acid–base balance, systemic levels of IL-6 and IL-10, and coagulation status were measured. After 1 h, there was a disproportionate increase in circulating neutrophils between saline and ALM groups despite an identical 45% fall in lymphocytes. Disproportionate increases also occurred in platelet counts 1 h after surgery, and saline controls had increased respiratory alkalosis at 6 h with higher lactate. Systemic inflammation was also evident after 1 h in both groups (plasma IL-6 increase) and was amplified in saline-controls after 6 h. The ALM group increased anti-inflammatory cytokine IL-10. Surgery was not associated with acute coagulopathy; however, there were significant reductions in fibrinolysis. Following a single laparotomy, ALM infusion appeared to reduce stress-induced release of neutrophils and platelets into the circulation, and reduced acid–base disturbance. After 1 h, both groups had similar IL-6 levels, but ALM animals had increased IL-10, indicating improved inflammatory balance. The uncoupling of inflammation and coagulation activation but not fibrinolysis may offer a unique opportunity to investigate differential activation of innate immunity in response to sterile injury in this model.
Collapse
Affiliation(s)
- Lisa Davenport
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Queensland, Australia
| | - Hayley L Letson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Queensland, Australia
| | - Geoffrey P Dobson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Queensland, Australia
| |
Collapse
|
41
|
Sharma R, Letson HL, Smith S, Dobson GP. Tranexamic acid leads to paradoxical coagulation changes during cardiac surgery: a pilot rotational thromboelastometry study. J Surg Res 2017; 217:100-112. [PMID: 28602219 DOI: 10.1016/j.jss.2017.05.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Revised: 04/19/2017] [Accepted: 05/01/2017] [Indexed: 01/09/2023]
Abstract
BACKGROUND Tranexamic acid (TXA) is increasingly used during major surgery with the goal to reduce excessive bleeding, transfusion requirements, and reexploration. Our aim was to examine the effect of TXA on coagulation at different times during cardiac surgery using rotational thromboelastometry. MATERIALS AND METHODS Nineteen adult males (EuroSCORE 4-5) were recruited consecutively for first-time cardiopulmonary bypass (CPB) surgery. Ten patients received TXA at anesthesia and nine received no TXA. Rotational thromboelastometry analysis occurred before anesthesia (baseline), after sternotomy, after CPB-heparinization and surgery, and after protamine administration-sternal closure. RESULTS A median sternotomy had no effect on clot time (CT), formation, amplitude, or lysis in non-TXA patients. In contrast, TXA patients had twofold prolonged clotting time (all-tests) and ∼30% reduced FIBTEM (A5-30) and maximum clot firmness, indicating reduced thrombin generation and lower clot fibrinogen. After CPB, CTs in both groups were prolonged, possibly linked to overheparinization. In addition, TXA patients had significantly decreased EXTEM (A5-30), suggesting lower clot strength. After protamine-sternal closure, clotting time remained prolonged in both groups, and TXA patients had a persistently 25%-33% lower FIBTEM (A5-30) and maximum clot firmness. TXA patients also had significantly reduced platelet numbers (37% from baseline), which continued Days 1 and 2. Maximum clot lysis was <10% indicating little or no hyperfibrinolysis during cardiac surgery. CONCLUSIONS In this nonrandomized, nonblinded, observational trial, patients in the TXA group displayed prolonged CTs and clot fibrinogen (FIBTEM A5-30) after sternotomy, decreased clot strength (EXTEM) after CPB/surgery, and acute thrombocytopenia after protamine-sternal closure. There was no significant decrease in clot lysis, questioning the need for TXA in this medium-risk group.
Collapse
Affiliation(s)
- Rajiv Sharma
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Queensland, Australia
| | - Hayley L Letson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Queensland, Australia
| | - Samuel Smith
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Queensland, Australia
| | - Geoffrey P Dobson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, James Cook University, Queensland, Australia.
| |
Collapse
|
42
|
Arsyad A, Dobson GP. Lidocaine relaxation in isolated rat aortic rings is enhanced by endothelial removal: possible role of K v, K ATP channels and A 2a receptor crosstalk. BMC Anesthesiol 2016; 16:121. [PMID: 27914476 PMCID: PMC5135802 DOI: 10.1186/s12871-016-0286-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 11/24/2016] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Lidocaine is an approved local anesthetic and Class 1B antiarrhythmic with a number of ancillary properties. Our aim was to investigate lidocaine's vasoreactivity properties in intact versus denuded rat thoracic aortic rings, and the effect of inhibitors of nitric oxide (NO), prostenoids, voltage-dependent Kv and KATP channels, membrane Na+/K+ pump, and A2a and A2b receptors. METHODS Aortic rings were harvested from adult male Sprague Dawley rats and equilibrated in an organ bath containing oxygenated, modified Krebs-Henseleit solution, pH 7.4, 37 °C. The rings were pre-contracted sub-maximally with 0.3 μM norepinephrine (NE), and the effect of increasing lidocaine concentrations was examined. Rings were tested for viability after each experiment with maximally dilating 100 μM papaverine. The drugs 4-aminopyridine (4-AP), glibenclamide, 5-hydroxydecanoate, ouabain, 8-(3-chlorostyryl) caffeine and PSB-0788 were examined. RESULTS All drugs tested had no significant effect on basal tension. Lidocaine relaxation in intact rings was biphasic between 1 and 10 μM (Phase 1) and 10 and 1000 μM (Phase 2). Mechanical removal of the endothelium resulted in further relaxation, and at lower concentrations ring sensitivity (% relaxation per μM lidocaine) significantly increased 3.5 times compared to intact rings. The relaxing factor(s) responsible for enhancing ring relaxation did not appear to be NO- or prostacyclin-dependent, as L-NAME and indomethacin had little or no effect on intact ring relaxation. In denuded rings, lidocaine relaxation was completely abolished by Kv channel inhibition and significantly reduced by antagonists of the MitoKATP channel, and to a lesser extent the SarcKATP channel. Curiously, A2a subtype receptor antagonism significantly inhibited lidocaine relaxation above 100 μM, but not the A2b receptor. CONCLUSIONS We show that lidocaine relaxation in rat thoracic aorta was biphasic and significantly enhanced by endothelial removal, which did not appear to be NO or prostacyclin dependent. The unknown factor(s) responsible for enhanced relaxation was significantly reduced by Kv inhibition, 5-HD inhibition, and A2a subtype inhibition indicating a potential role for crosstalk in lidocaine's vasoreactivity.
Collapse
Affiliation(s)
- Aryadi Arsyad
- Heart, Trauma and Sepsis Research Laboratory, Australian Institute of Tropical Health and Medicine, College of Medicine and Dentistry, James Cook University, 1 James Cook Drive, 4811 Queensland, Australia
- Physiology Department, Medical Faculty, Hasanuddin University, Jl. Perintis Kemerdekaan, Km. 10, 90213 Tamalanrea, Makassar Indonesia
| | - Geoffrey P. Dobson
- Heart, Trauma and Sepsis Research Laboratory, Australian Institute of Tropical Health and Medicine, College of Medicine and Dentistry, James Cook University, 1 James Cook Drive, 4811 Queensland, Australia
| |
Collapse
|
43
|
Hamaoui K, Aftab A, Gowers S, Boutelle M, Cook T, Rudd D, Dobson GP, Papalois V. An ex vivo comparison of adenosine and lidocaine solution and University of Wisconsin solution for hypothermic machine perfusion of porcine kidneys: potential for development. J Surg Res 2016; 208:219-229. [PMID: 27993213 DOI: 10.1016/j.jss.2016.08.068] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 07/29/2016] [Accepted: 08/18/2016] [Indexed: 01/13/2023]
Abstract
BACKGROUND The optimal hypothermic machine perfusion (HMP) solution has not yet been developed. An adenosine and lidocaine (AL) solution has been shown to be protective in cardiac preservation. The aim of the present study was to examine a modified AL solution with low Ca2+, 16 mM Mg2+, and 4% albumin on kidney preservation compared with University Wisconsin solution (UW). METHODS Twenty donation of organs after cardiac death porcine kidneys underwent HMP for 10 h (AL, n = 10; UW, n = 10) and then 2 h of normothermic reperfusion. Perfusion dynamics, functional parameters, histology, and real-time microdialysis were used to assess kidney responses and viability. RESULTS During HMP, modified AL-perfused kidneys maintained higher flow rates (21.5 versus 17.9 mL/min/100 g, P = 0.01), with perfusion flow index during the first 3 h 25% greater than with UW (AL = 0.50 ± 0.2, UW = 0.40 ± 0.17 mL/min/100 g/mmHg; P = 0.03), followed by an increase in UW kidneys which was not significantly different to AL over the remaining 7 h (0.54 versus 0.55 mL/min/100 g/mmHg, respectively). During warm reperfusion, there were no significant differences between the two HMP groups in creatinine clearance, oxygen, and glucose consumption between groups. Modified AL kidneys had significantly lower perfusate lactates (3.1 versus 4.1 mmol/L, P = 0.04) during reperfusion and lower cortical lactate levels (AL = 0.66 ± 0.31, UW = 0.89 ± 0.53 mM, P = 0.33). Histology showed similar degrees of reperfusion injury. CONCLUSIONS We conclude that HMP with modified AL solution showed improved perfusion compared with UW and lower perfusate lactate levels during warm reperfusion. Further modification of the AL composition is warranted and may lead to more rapid kidney stabilization and improved graft viability assessment, potentially expanding donor pools.
Collapse
Affiliation(s)
- Karim Hamaoui
- Department of Surgery, Imperial College London, London, United Kingdom.
| | - Adeel Aftab
- Department of Surgery, Imperial College London, London, United Kingdom
| | - Sally Gowers
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | - Martyn Boutelle
- Department of Bioengineering, Imperial College London, London, United Kingdom
| | - Terry Cook
- Imperial College Renal and Transplant Centre, Hammersmith Hospital, Imperial College Healthcare NHS Trust, London, United Kingdom
| | - Donna Rudd
- College of Public Health, Medical and Vet Sciences, James Cook University, Townsville, Queensland, Australia
| | - Geoffrey P Dobson
- Heart, Trauma and Sepsis Research Laboratory, College of Medicine and Dentistry, AITHM, James Cook University, Townsville, Queensland, Australia
| | - Vassilios Papalois
- Department of Surgery, Imperial College London, London, United Kingdom; Imperial College Renal and Transplant Centre, Hammersmith Hospital, Imperial College Healthcare NHS Trust, London, United Kingdom
| |
Collapse
|
44
|
Arsyad A, Dobson GP. Adenosine relaxation in isolated rat aortic rings and possible roles of smooth muscle Kv channels, KATP channels and A2a receptors. BMC Pharmacol Toxicol 2016; 17:23. [PMID: 27211886 PMCID: PMC4876563 DOI: 10.1186/s40360-016-0067-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 04/29/2016] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND An area of ongoing controversy is the role adenosine to regulate vascular tone in conduit vessels that regulate compliance, and the role of nitric oxide (NO), potassium channels and receptor subtypes involved. The aim of our study was to investigate adenosine relaxation in rat thoracic aortic rings, and the effect of inhibitors of NO, prostanoids, Kv, KATP channels, and A2a and A2b receptors. METHODS Aortic rings were freshly harvested from adult male Sprague Dawley rats and equilibrated in an organ bath containing oxygenated, modified Krebs-Henseleit solution, 11 mM glucose, pH 7.4, 37 °C. Isolated rings were pre-contracted sub-maximally with 0.3 μM norepinephrine (NE), and the effect of increasing concentrations of adenosine (1 to 1000 μM) were examined. The drugs L-NAME, indomethacin, 4-aminopyridine (4-AP), glibenclamide, 5-hydroxydecanoate, ouabain, 8-(3-chlorostyryl) caffeine and PSB-0788 were examined in intact and denuded rings. Rings were tested for viability after each experiment. RESULTS Adenosine induced a dose-dependent, triphasic relaxation response, and the mechanical removal of the endothelium significantly deceased adenosine relaxation above 10 μM. Interestingly, endothelial removal significantly decreased the responsiveness (defined as % relaxation per μM adenosine) by two-thirds between 10 and 100 μM, but not in the lower (1-10 μM) or higher (>100 μM) ranges. In intact rings, L-NAME significantly reduced relaxation, but not indomethacin. Antagonists of voltage-dependent Kv (4-AP), sarcolemma KATP (glibenclamide) and mitochondrial KATP channels (5-HD) led to significant reductions in relaxation in both intact and denuded rings, with ouabain having little or no effect. Adenosine-induced relaxation appeared to involve the A2a receptor, but not the A2b subtype. CONCLUSIONS It was concluded that adenosine relaxation in NE-precontracted rat aortic rings was triphasic and endothelium-dependent above 10 μM, and relaxation involved endothelial nitric oxide (not prostanoids) and a complex interplay between smooth muscle A2a subtype and voltage-dependent Kv, SarcKATP and MitoKATP channels. The possible in vivo significance of the regulation of arterial compliance to left ventricular function coupling is discussed.
Collapse
Affiliation(s)
- Aryadi Arsyad
- Physiology Department, Medical Faculty, Hasanuddin University, Jl. Perintis Kemerdekaan, Km. 10, Tamalanrea, Makassar, 90213, Indonesia
| | - Geoffrey P Dobson
- Heart, Trauma and Sepsis Research Laboratory, Australian Institute of Tropical Health and Medicine, College of Medicine and Dentistry, James Cook University, 1 James Cook Drive, Queensland, 4811, Australia.
| |
Collapse
|
45
|
Onorati F, Dobson GP, San Biagio L, Abbasciano R, Fanti D, Covajes C, Menon T, Gottin L, Biancari F, Mazzucco A, Faggian G. Superior Myocardial Protection Using “Polarizing” Adenosine, Lidocaine, and Mg 2+ Cardioplegia in Humans. J Am Coll Cardiol 2016; 67:1751-3. [DOI: 10.1016/j.jacc.2015.12.071] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 12/10/2015] [Accepted: 12/22/2015] [Indexed: 10/22/2022]
|
46
|
Abstract
Despite a technically perfect procedure, surgical stress can determine the success or failure of an operation. Surgical trauma is often referred to as the "neglected step-child" of global health in terms of patient numbers, mortality, morbidity, and costs. A staggering 234 million major surgeries are performed every year, and depending upon country and institution, up to 4% of patients will die before leaving hospital, up to 15% will have serious post-operative morbidity, and 5-15% will be readmitted within 30 days. These percentages equate to around 1000 deaths and 4000 major complications every hour, and it has been estimated that 50% may be preventable. New frontline drugs are urgently required to make major surgery safer for the patient and more predictable for the surgeon. We review the basic physiology of the stress response from neuroendocrine to genomic systems, and discuss the paucity of clinical data supporting the use of statins, beta-adrenergic blockers and calcium-channel blockers. Since cardiac-related complications are the most common, particularly in the elderly, a key strategy would be to improve ventricular-arterial coupling to safeguard the endothelium and maintain tissue oxygenation. Reduced O2 supply is associated with glycocalyx shedding, decreased endothelial barrier function, fluid leakage, inflammation, and coagulopathy. A healthy endothelium may prevent these "secondary hit" complications, including possibly immunosuppression. Thus, the four pillars of whole body resynchronization during surgical trauma, and targets for new therapies, are: (1) the CNS, (2) the heart, (3) arterial supply and venous return functions, and (4) the endothelium. This is termed the Central-Cardio-Vascular-Endothelium (CCVE) coupling hypothesis. Since similar sterile injury cascades exist in critical illness, accidental trauma, hemorrhage, cardiac arrest, infection and burns, new drugs that improve CCVE coupling may find wide utility in civilian and military medicine.
Collapse
Affiliation(s)
- Geoffrey P Dobson
- Heart, Trauma and Sepsis Research Laboratory, Australian Institute of Tropical Health and Medicine, College of Medicine and Dentistry, James Cook University , Townsville, QLD , Australia
| |
Collapse
|
47
|
Granfeldt A, Letson HL, Dobson GP, Shi W, Vinten-Johansen J, Tønnesen E. Adenosine, lidocaine and Mg2+ improves cardiac and pulmonary function, induces reversible hypotension and exerts anti-inflammatory effects in an endotoxemic porcine model. Crit Care 2014; 18:682. [PMID: 25497775 PMCID: PMC4301798 DOI: 10.1186/s13054-014-0682-y] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Accepted: 11/20/2014] [Indexed: 12/24/2022]
Abstract
Introduction The combination of Adenosine (A), lidocaine (L) and Mg2+ (M) (ALM) has demonstrated cardioprotective and resuscitative properties in models of cardiac arrest and hemorrhagic shock. This study evaluates whether ALM also demonstrates organ protective properties in an endotoxemic porcine model. Methods Pigs (37 to 42 kg) were randomized into: 1) Control (n = 8) or 2) ALM (n = 8) followed by lipopolysaccharide infusion (1 μg∙kg-1∙h-1) for five hours. ALM treatment consisted of 1) a high dose bolus (A (0.82 mg/kg), L (1.76 mg/kg), M (0.92 mg/kg)), 2) one hour continuous infusion (A (300 μg∙kg-1 ∙min-1), L (600 μg∙kg-1 ∙min-1), M (336 μg∙kg-1 ∙min-1)) and three hours at a lower dose (A (240∙kg-1∙min-1), L (480 μg∙kg-1∙min-1), M (268 μg∙kg-1 ∙min-1)); controls received normal saline. Hemodynamic, cardiac, pulmonary, metabolic and renal functions were evaluated. Results ALM lowered mean arterial pressure (Mean value during infusion period: ALM: 47 (95% confidence interval (CI): 44 to 50) mmHg versus control: 79 (95% CI: 75 to 85) mmHg, P <0.0001). After cessation of ALM, mean arterial pressure immediately increased (end of study: ALM: 88 (95% CI: 81 to 96) mmHg versus control: 86 (95% CI: 79 to 94) mmHg, P = 0.72). Whole body oxygen consumption was significantly reduced during ALM infusion (ALM: 205 (95% CI: 192 to 217) ml oxygen/min versus control: 231 (95% CI: 219 to 243) ml oxygen/min, P = 0.016). ALM treatment reduced pulmonary injury evaluated by PaO2/FiO2 ratio (ALM: 388 (95% CI: 349 to 427) versus control: 260 (95% CI: 221 to 299), P = 0.0005). ALM infusion led to an increase in heart rate while preserving preload recruitable stroke work. Creatinine clearance was significantly lower during ALM infusion but reversed after cessation of infusion. ALM reduced tumor necrosis factor-α peak levels (ALM 7121 (95% CI: 5069 to 10004) pg/ml versus control 11596 (95% CI: 9083 to 14805) pg/ml, P = 0.02). Conclusion ALM infusion induces a reversible hypotensive and hypometabolic state, attenuates tumor necrosis factor-α levels and improves cardiac and pulmonary function, and led to a transient drop in renal function that was reversed after the treatment was stopped.
Collapse
Affiliation(s)
- Asger Granfeldt
- Department of Anesthesiology, Aarhus University Hospital, Nørrebrogade 44 building 21 1st floor 8000, Aarhus, Denmark. .,Department of Anesthesiology, Regional Hospital of Randers, Skovlyvej 1, 8930, Randers, Denmark.
| | - Hayley L Letson
- Heart, Trauma & Sepsis Research Laboratory, Australian Institute of Tropical Health and Medicine, School of Medicine and Dentistry, James Cook University, Pharmacy and Medical Research Building 47, Rm 113B, Townsville, Queensland, Australia.
| | - Geoffrey P Dobson
- Heart, Trauma & Sepsis Research Laboratory, Australian Institute of Tropical Health and Medicine, School of Medicine and Dentistry, James Cook University, Pharmacy and Medical Research Building 47, Rm 113B, Townsville, Queensland, Australia.
| | - Wei Shi
- The Cardiothoracic Research Laboratory, Carlyle Fraser Heart Center, Emory University School of Medicine, 387 Technology Circle Suite 180, Atlanta, Georgia 30313, USA.
| | - Jakob Vinten-Johansen
- The Cardiothoracic Research Laboratory, Carlyle Fraser Heart Center, Emory University School of Medicine, 387 Technology Circle Suite 180, Atlanta, Georgia 30313, USA.
| | - Else Tønnesen
- Department of Anesthesiology, Aarhus University Hospital, Nørrebrogade 44 building 21 1st floor 8000, Aarhus, Denmark.
| |
Collapse
|
48
|
|
49
|
Djabir Y, Letson HL, Dobson GP. Adenosine, lidocaine, and Mg2+ (ALM™) increases survival and corrects coagulopathy after eight-minute asphyxial cardiac arrest in the rat. Shock 2014; 40:222-32. [PMID: 23846412 DOI: 10.1097/shk.0b013e3182a03566] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
INTRODUCTION No drug therapy has demonstrated improved survival following cardiac arrest (CA) of cardiac or noncardiac origin. In an effort to translate the cardiorescue properties of Adenocaine (adenosine and lidocaine) and magnesium sulfate (ALM) from cardiac surgery and hemorrhagic shock to resuscitation, we examined the effect of ALM on hemodynamic rescue and coagulopathy following asphyxial-induced CA in the rat. METHODS Nonheparinized animals (400-500 g, n = 39) were randomly assigned to 0.9% saline (n = 12) and 0.9% saline ALM (n = 10) groups. After baseline data were acquired, the animal was surface cooled (33°C-34°C) and the ventilator line clamped for 8 min inducing CA; 0.5 mL of solution was injected intravenously followed by 60-s chest compressions (300/min), and rats were rewarmed. Return of spontaneous circulation (ROSC), mean arterial pressure, heart rate, and rectal temperature were recorded for 2 h. Additional rats were randomized for rotation thromboelastometry measurements (n = 17). RESULTS Rats treated with ALM had a significant survival benefit (100% ALM vs. 67% controls achieved ROSC) and generated a higher mean arterial pressure than did controls after 75 min (81 vs. 72 mmHg at 120 min, P < 0.05). In all rats, rotation thromboelastometry lysis index decreased during CA, implying hyperfibrinolysis. Control ROSC survivors displayed hypocoagulopathy (prolonged EXTEM/INTEM clotting time, clot formation time, prothrombin time, activated partial thromboplastin time), decreased maximal clot firmness, lowered elasticity, and lowered clot amplitudes but no change in lysis index. These coagulation abnormalities were corrected by ALM at 120 min after ROSC. CONCLUSIONS Small bolus of 0.9% NaCl ALM improved survival and hemodynamics following nonhemorrhagic, asphyxial CA and corrected prolonged clot times and clot retraction compared with controls.
Collapse
Affiliation(s)
- Yulia Djabir
- Heart and Trauma Research Laboratory, Physiology and Pharmacology, James Cook University, Queensland, Australia
| | | | | |
Collapse
|
50
|
Griffin M, Letson HL, Dobson GP. Optimization of the rodent model of polymicrobial sepsis. Int Immunopharmacol 2014; 19:405. [PMID: 24485942 DOI: 10.1016/j.intimp.2014.01.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Accepted: 01/17/2014] [Indexed: 11/24/2022]
Affiliation(s)
- Maddison Griffin
- Heart, Trauma & Sepsis Research Laboratory, Australian Institute of Tropical Health and Medicine, School of Medicine and Dentistry, James Cook University, Townsville, Queensland, Australia 4811.
| | - Hayley L Letson
- Heart, Trauma & Sepsis Research Laboratory, Australian Institute of Tropical Health and Medicine, School of Medicine and Dentistry, James Cook University, Townsville, Queensland, Australia 4811.
| | - Geoffrey P Dobson
- Heart, Trauma & Sepsis Research Laboratory, Australian Institute of Tropical Health and Medicine, School of Medicine and Dentistry, James Cook University, Townsville, Queensland, Australia 4811.
| |
Collapse
|