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Ruíz‐López P, Martens A, Chantillon L, Schauvliege S. Pulmonary and laryngeal oedema before induction of anaesthesia in a sheep. Vet Record Case Reports 2022. [DOI: 10.1002/vrc2.362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Patricia Ruíz‐López
- Department of Surgery and Anaesthesia of Domestic Animals, Faculty of Veterinary Medicine University of Ghent Merelbeke Belgium
| | - Ann Martens
- Department of Surgery and Anaesthesia of Domestic Animals, Faculty of Veterinary Medicine University of Ghent Merelbeke Belgium
| | - Laurens Chantillon
- Department of Internal Medicine of Large Domestic Animals, Faculty of Veterinary Medicine University of Ghent Merelbeke Belgium
| | - Stijn Schauvliege
- Department of Surgery and Anaesthesia of Domestic Animals, Faculty of Veterinary Medicine University of Ghent Merelbeke Belgium
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Gonçalves-Ferri WA, Albuquerque AAS, Evora PM, Evora PRB. Methylene Blue not Contraindicated in Treating Hemodynamic Instability in Pediatric and Neonate Patients. Curr Pediatr Rev 2022; 18:2-8. [PMID: 34397332 DOI: 10.2174/1573396317666210816105812] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 06/14/2021] [Accepted: 06/17/2021] [Indexed: 11/22/2022]
Abstract
The present review was carried out to describe publications on the use of methylene blue (MB) in pediatrics and neonatology, discussing dose, infusion rate, action characteristics, and possible benefits for a pediatric patient group. The research was performed on the data sources PubMed, BioMed Central, and Embase (updated on Aug 31, 2020) by two independent investigators. The selected articles included human studies that evaluated MB use in pediatric or neonatal patients with vasoplegia due to any cause, regardless of the applied methodology. The MB use and 0 to 18-years-old patients with vasodilatory shock were the adopted criteria. Exclusion criteria were the use of MB in patients without vasoplegia and patients ≥ 18-years-old. The primary endpoint was the increase in mean arterial pressure (MAP). Side effects and dose were also evaluated. Eleven studies were found, of which 10 were case reports, and 1 was a randomized clinical study. Only two of these studies were with neonatal patients (less than 28 days-old), reporting a small number of cases (1 and 6). All studies described the positive action of MB on MAP, allowing the decrease of vasoactive amines in several of them. No severe side effects or death related to the use of the medication were reported. The maximum dose used was 2 mg/kg, but there was no consensus on the infusion rate and drug administration timing. Finally, no theoretical or experimental basis sustains the decision to avoid MB in children claiming it can cause pulmonary hypertension. The same goes for the concern of a possible deleterious effect on inflammatory distress syndrome.
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Affiliation(s)
- Walusa A Gonçalves-Ferri
- Department of Pediatrics, Ribeirão Preto Medical School-University of São Paulo, São Paulo, Brazil
| | - Agnes A S Albuquerque
- Department of Surgery and Anatomy, Ribeirão Preto Medical School-University of São Paulo, São Paulo, Brazil
| | - Patricia Martinez Evora
- Department of Surgery and Anatomy, Ribeirão Preto Medical School-University of São Paulo, São Paulo, Brazil
| | - Paulo R B Evora
- Department of Surgery and Anatomy, Ribeirão Preto Medical School-University of São Paulo, São Paulo, Brazil
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Abstract
Endotoxaemia is an inflammatory condition which happens due to the presence of outer cell wall layer of Gram-negative bacteria in blood circulation, containing lipopolysaccharide commonly known as endotoxin. This condition causes high mortality in affected animals and sheep are highly susceptible in this regard. Several researchers have emphasised the therapeutic regimens of endotoxaemia and its sequels in sheep. Furthermore, sheep are among the most commonly used animal species in experimental studies on endotoxaemia, and for the past five decades, ovine models have been employed to evaluate different aspects of endotoxaemia. Currently, there are several studies on experimentally induced endotoxaemia in sheep, and information regarding novel therapeutic protocols in this species contributes to better understanding and treating the condition. This review aims to specifically introduce various treatment methods of endotoxaemia in sheep.
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Affiliation(s)
- A. Chalmeh
- Department of Clinical Sciences, School of Veterinary Medicine, Shiraz University, Shiraz, Iran
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Gonçalves-Ferri WA, Albuquerque AAS, de Castro RSAP, Ferreira CHF, Oharomari LK, Silva Lessa DF, Evora PRB. Methylene Blue to Neonatal Septic Shock treatment in neonate pigs . Clinics (Sao Paulo) 2022; 77:100139. [PMID: 36459779 PMCID: PMC9706526 DOI: 10.1016/j.clinsp.2022.100139] [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] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 10/06/2022] [Accepted: 11/01/2022] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE The authors design an animal model of neonatal sepsis to analyze the treatment of neonatal septic shock with Methylene Blue (MB) in a swine model. METHODS The study design included twenty male newborn pigs divided into four groups: 1) The control group; 2) The sepsis group (induced with lipopolysaccharide); 3) The MB group, and 4) The MB-treated sepsis group. Septic shock was defined as Blood Pressure (BP) dropping 20% below the baseline value. Continuous Blood Pressure (BP), Nitric Oxide (NO) levels, cyclic Guanosine Monophosphate (cGMP), malondialdehyde acid, base excess, lactate, arterial blood gases, hematocrit, and echocardiography were analyzed. RESULTS The BP of the sepsis group treated with MB showed a slight improvement in the first hour after treatment; however, a significant difference was not observed compared to the untreated sepsis group. Besides hemodynamic stability, the current study did not show symptomatic pulmonary hypertension, suggesting that MB was safe in neonates and children. An improvement in Base Excel (BE) levels after MB administration in septic animals may indicate a possible improvement in microcirculation. CONCLUSION The MB improved biomarkers related to septic shock prognosis, although an improvement in the blood levels could not be detected. MB might be a beneficial drug for hemodynamic instability in infants.
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Affiliation(s)
| | | | | | | | - Luis K Oharomari
- Faculdade de Medicina de Ribeirão Preto (FMRP), Universidade de São Paulo, Ribeirão Preto, SP, Brazil
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Cassiano Silveira AP, Vento DA, Albuquerque AAS, Celotto AC, Tefé-Silva C, Ramos SG, Rubens de Nadai T, Rodrigues AJ, Poli-Neto OB, Evora PRB. Effects of methylene blue in acute lung injury induced by oleic acid in rats. Ann Transl Med 2016; 4:8. [PMID: 26855944 PMCID: PMC4716953 DOI: 10.3978/j.issn.2305-5839.2015.12.51] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 12/25/2015] [Indexed: 11/14/2022]
Abstract
BACKGROUND In acute lung injury (ALI), rupture of the alveolar-capillary barrier determines the protein-rich fluid influx into alveolar spaces. Previous studies have reported that methylene blue (MB) attenuates such injuries. This investigation was carried out to study the MB effects in pulmonary capillary permeability. METHODS Wistar rats were divided into five groups: (I) Sham: saline bolus; (II) MB, MB infusion for 2 h; (III) oleic acid (OA), OA bolus; (IV) MB/OA, MB infusion for 2 h, and at 5 min after from the beginning, concurrently with an OA bolus; and (V) OA/MB, OA bolus, and after 2 h, MB infusion for 2 h. After 4 h, blood, bronchoalveolar lavage (BAL), and lung tissue were collected from all groups for analysis of plasma and tissue nitric oxide, calculation of the wet weight to dry weight ratio (WW/DW), and histological examination of lung tissue. Statistical analysis was performed using nonparametric test. RESULTS Although favourable trends have been observed for permeability improvement parameters (WW/WD and protein), the results were not statistically significant. However, histological analysis of lung tissue showed reduced lesion areas in both pre- and post-treatment groups. CONCLUSIONS The data collected using this experimental model was favourable only through macroscopic and histological analysis. These observations are valid for both MB infusions before or after induction of ALI.
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Evora PRB, Alves Junior L, Ferreira CA, Menardi AC, Bassetto S, Rodrigues AJ, Scorzoni Filho A, Vicente WVDA. Twenty years of vasoplegic syndrome treatment in heart surgery. Methylene blue revised. Braz J Cardiovasc Surg 2015; 30:84-92. [PMID: 25859872 PMCID: PMC4389523 DOI: 10.5935/1678-9741.20140115] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [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: 04/24/2014] [Accepted: 10/12/2014] [Indexed: 11/20/2022] Open
Abstract
Objective This study was conducted to reassess the concepts established over the past 20
years, in particular in the last 5 years, about the use of methylene blue in the
treatment of vasoplegic syndrome in cardiac surgery. Methods A wide literature review was carried out using the data extracted from: MEDLINE,
SCOPUS and ISI WEB OF SCIENCE. Results The reassessed and reaffirmed concepts were 1) MB is safe in the recommended doses
(the lethal dose is 40 mg/kg); 2) MB does not cause endothelial dysfunction; 3)
The MB effect appears in cases of NO up-regulation; 4) MB is not a
vasoconstrictor, by blocking the cGMP pathway it releases the cAMP pathway,
facilitating the norepinephrine vasoconstrictor effect; 5) The most used dosage is
2 mg/kg as IV bolus, followed by the same continuous infusion because plasma
concentrations sharply decrease in the first 40 minutes; and 6) There is a
possible "window of opportunity" for MB's effectiveness. In the last five years,
major challenges were: 1) Observations about side effects; 2) The need for
prophylactic and therapeutic guidelines, and; 3) The need for the establishment of
the MB therapeutic window in humans. Conclusion MB action to treat vasoplegic syndrome is time-dependent. Therefore, the great
challenge is the need, for the establishment the MB therapeutic window in humans.
This would be the first step towards a systematic guideline to be followed by
possible multicenter studies.
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Affiliation(s)
- Paulo Roberto Barbosa Evora
- Department of Surgery and Anatomy, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Lafaiete Alves Junior
- Department of Surgery and Anatomy, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Cesar Augusto Ferreira
- Department of Surgery and Anatomy, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Antônio Carlos Menardi
- Department of Surgery and Anatomy, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Solange Bassetto
- Department of Surgery and Anatomy, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Alfredo José Rodrigues
- Department of Surgery and Anatomy, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Adilson Scorzoni Filho
- Department of Surgery and Anatomy, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
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Talley Watts L, Long JA, Boggs RC, Manga H, Huang S, Shen Q, Duong TQ. Delayed Methylene Blue Improves Lesion Volume, Multi-Parametric Quantitative Magnetic Resonance Imaging Measurements, and Behavioral Outcome after Traumatic Brain Injury. J Neurotrauma 2015; 33:194-202. [PMID: 25961471 DOI: 10.1089/neu.2015.3904] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Traumatic brain injury (TBI) remains a primary cause of death and disability in both civilian and military populations worldwide. There is a critical need for the development of neuroprotective agents that can circumvent damage and provide functional recovery. We previously showed that methylene blue (MB), a U.S. Food and Drug Administration-grandfathered drug with energy-enhancing and antioxidant properties, given 1 and 3 h post-TBI, had neuroprotective effects in rats. This study aimed to further investigate the neuroprotection of delayed MB treatment (24 h postinjury) post-TBI as measured by lesion volume and functional outcomes. Comparisons were made with vehicle and acute MB treatment. Multi-modal magnetic resonance imaging and behavioral studies were performed at 1 and 3 h and 2, 7, and 14 days after an impact to the primary forelimb somatosensory cortex. We found that delaying MB treatment 24 h postinjury still minimized lesion volume and functional deficits, compared to vehicle-treated animals. The data further support the potential for MB as a neuroprotective treatment, especially when medical teatment is not readily available. MB has an excellent safety profile and is clinically approved for other indications. MB clinical trials on TBI can thus be readily explored.
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Affiliation(s)
- Lora Talley Watts
- 1 Research Imaging Institute, University of Texas Health Science Center , San Antonio, Texas.,2 Departments of Cellular and Structure Biology, University of Texas Health Science Center , San Antonio, Texas.,3 Department of Neurology, University of Texas Health Science Center , San Antonio, Texas
| | - Justin Alexander Long
- 1 Research Imaging Institute, University of Texas Health Science Center , San Antonio, Texas
| | - Robert Cole Boggs
- 1 Research Imaging Institute, University of Texas Health Science Center , San Antonio, Texas
| | - Hemanth Manga
- 1 Research Imaging Institute, University of Texas Health Science Center , San Antonio, Texas
| | - Shiliang Huang
- 1 Research Imaging Institute, University of Texas Health Science Center , San Antonio, Texas
| | - Qiang Shen
- 1 Research Imaging Institute, University of Texas Health Science Center , San Antonio, Texas
| | - Timothy Q Duong
- 1 Research Imaging Institute, University of Texas Health Science Center , San Antonio, Texas.,3 Department of Neurology, University of Texas Health Science Center , San Antonio, Texas.,4 Department of Ophthalmology, University of Texas Health Science Center , San Antonio, Texas.,5 Research Division, South Texas Veterans Health Care System , San Antonio, Texas
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Abstract
Postperfusion lung syndrome is rare but can be lethal. The underlying mechanism
remains uncertain but triggering inflammatory cascades have become an accepted
etiology. A better understanding of the pathophysiology and the roles of inflammatory
mediators in the development of the syndrome is imperative in the determination of
therapeutic options and promotion of patients' prognosis and survival. Postperfusion
lung syndrome is similar to adult respiratory distress syndrome in clinical features,
diagnostic approaches and management strategies. However, the etiologies and
predisposing risk factors may differ between each other. The prognosis of the
postperfusion lung syndrome can be poorer in comparison to acute respiratory distress
syndrome due to the secondary multiple organ failure and triple acid-base imbalance.
Current management strategies are focusing on attenuating inflammatory responses and
preventing from pulmonary ischemia-reperfusion injury. Choices of cardiopulmonary
bypass circuit and apparatus, innovative cardiopulmonary bypass techniques, modified
surgical maneuvers and several pharmaceutical agents can be potential preventive
strategies for acute lung injury during cardiopulmonary bypass.
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Affiliation(s)
- Shi-Min Yuan
- Teaching Hospital, The First Hospital of Putian, Fujian Medical University, Putian, China
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Abstract
BACKGROUND We recently reported that post-pneumonectomy pulmonary oedema (PPO) occurs after ventilating the remaining lung with excessive tidal volumes. Studies in small animals have indicated that nitric oxide (NO) release increases in hyper-inflated lungs, but confirmatory evidence from larger animals is still lacking. We hypothesized that PPO could be prevented by methylene blue (MB), an inhibitor of NO synthase. METHODS Sheep were subjected to a right-sided pneumonectomy (PE) and randomly assigned to a protectively ventilated group ((PROTV group, n=7) with tidal volumes of 6 ml/kg at 20 inflations/min and a positive end-expiratory pressure (PEEP) of 2 cmH(2)O, and two groups undergoing 'injurious ventilation' (INJV) with tidal volumes of 12 ml/kg and zero end-expiratory pressure (ZEEP), a control group (INJV group, n=7) and a treatment group subjected to MB 1 h after PE (INJV+MB group, n=7). Haemodynamic variables, lung mechanics, blood gases and plasma nitrites and nitrates (NOx) were determined. RESULTS PE reduced pulmonary blood volume, extravascular lung water (EVLWI) and quasistatic lung compliance in all groups, in parallel with a rise in peak airway pressure (P<0.05). In the INJV group, pulmonary arterial pressure, EVLWI and pulmonary vascular permeability index increased and arterial oxygenation decreased towards cessation of the experiments. These changes were not antagonized by MB. Plasma NOx increased in all the groups compared with baseline, but with no intergroup difference. CONCLUSION MB did not reduce PPO and accumulation of NOx in sheep subjected to ventilation with excessive tidal volumes and ZEEP.
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Affiliation(s)
- E V Suborov
- Department of Anaesthesiology, Institute of Clinical Medicine, Faculty of Health Sciences, University of Tromsø, Tromsø, Norway
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Waerhaug K, Kuzkov VV, Kuklin VN, Mortensen R, Nordhus KC, Kirov MY, Bjertnaes LJ. Inhaled aerosolised recombinant human activated protein C ameliorates endotoxin-induced lung injury in anaesthetised sheep. Crit Care 2009; 13:R51. [PMID: 19356243 PMCID: PMC2689497 DOI: 10.1186/cc7777] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/07/2009] [Revised: 04/02/2009] [Accepted: 04/08/2009] [Indexed: 01/06/2023]
Abstract
Introduction We recently demonstrated that intravenously infused recombinant human activated protein C (APC) attenuates ovine lipopolysaccharide (LPS)-induced lung injury. In this study, our aim was to find out whether treatment with inhaled aerosolised APC (inhAPC) prevents formation of increased lung densities and oedema and derangement of oxygenation during exposure to LPS. Methods Sheep were anaesthetised during placement of intravascular introducers. After one to four days of recovery from instrumentation, the animals were re-anaesthetised, endotracheally intubated and mechanically ventilated throughout a six-hour experiment where the sheep underwent quantitative lung computed tomography. Sheep were randomly assigned to one of three groups: a sham-operated group (n = 8) receiving inhaled aerosolised saline from two hours after the start of the experiment; a LPS group (n = 8) receiving an intravenous infusion of LPS 20 ng/kg per hour and, after two hours, inhaled aerosolised saline over the next four hours; a LPS+inhAPC group (n = 8) receiving an intravenous infusion of LPS 20 ng/kg per hour and, after two hours, aerosolised APC 48 μg/kg per hour inhaled throughout the experiment. Data were analysed with analysis of variance; P less than 0.05 was regarded as significant. Results An infusion of LPS was associated with a reduction of well-aerated lung volume and a rapid fall in arterial oxygenation that were both significantly antagonised by inhaled APC. Pulmonary vascular pressures and extravascular lung water index increased significantly during exposure to LPS, but inhaled APC had no effect on these changes. Conclusions Inhalation of aerosolised APC attenuates LPS-induced lung injury in sheep by preventing a decline in the volume of aerated lung tissue and improving oxygenation.
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Affiliation(s)
- Kristine Waerhaug
- Department of Anesthesiology, Institute of Clinical Medicine, Faculty of Medicine, University of Tromsø, N-9037 Tromsø, Norway
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Abstract
The majority of nitric oxide (NO) effects in the respiratory system are caused by stimulation of soluble guanylyl cyclase (sGC) with subsequent increase of cyclic guanosine monophosphate (cGMP) production. The importance of this mechanism of NO action in airway hyperreactivity (AHR) pathogenesis is unknown. Therefore, the aim of our experiment was to examine the changes of airway reactivity enhanced by toluene vapor exposure in the presence or inhibition of sGC activity in guinea pigs. Animals were treated with a nonspecific sGC inhibitor, methylene blue, in a dose of 50 or 100 mg/kg body weight, administered by intraperitoneal injection 30 min before or after exposure to toluene vapors. The toluene exposure lasted 2 hr in each of 3 consecutive days under in vivo conditions. Thereafter, the tracheal and lung tissue smooth muscle response to cumulative doses of mediators (histamine or acetylcholine) was recorded under in vitro conditions. The exposure to toluene vapors significantly increased the airway reactivity to both mediators in comparison with the healthy animal group. The administration of methylene blue decreased the amplitude of airway smooth muscle contraction in toluene-induced hyperreactivity. The decreases were dependent on the inhibitor doses, on a regimen of administration (before or after toluene inhalation), the level of the respiratory system (trachea, lung), and the bronchoconstrictor mediators. Our results suggest that the interaction between NO and sGC may be important for airway reactivity changes, but other mechanisms of NO action are important in AHR pathogenesis, too.
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Affiliation(s)
- Martina Antosová
- Department of Nursing, Comenius University Bratislava, Jessenius Faculty of Medicine, Martin, Slovakia.
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Kuklin VN, Kirov MY, Evgenov OV, Sovershaev MA, Sjöberg J, Kirova SS, Bjertnaes LJ. Novel endothelin receptor antagonist attenuates endotoxin-induced lung injury in sheep. Crit Care Med 2004; 32:766-73. [PMID: 15090960 DOI: 10.1097/01.ccm.0000114575.08269.f6] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [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: 11/26/2022]
Abstract
OBJECTIVE To evaluate the cardiopulmonary effects of the novel endothelin receptor antagonist tezosentan in endotoxin-induced lung injury in sheep and to assess the dose response to tezosentan and endothelin-1 in healthy sheep. DESIGN Prospective, randomized, controlled experimental study. SETTING University animal laboratory. SUBJECTS Twenty-one yearling sheep. INTERVENTIONS Seventeen awake, chronically instrumented sheep were subjected to intravenous infusion of Ringer's lactate for 24 hrs. The animals were randomly assigned to a sham-operated group (n = 3), a lipopolysaccharide group (n = 7) receiving an intravenous infusion of Escherichia coli lipopolysaccharide 15 ng x kg x min, and a tezosentan group (n = 7) subjected to lipopolysaccharide and, from 4 hrs, an intravenous injection of tezosentan 3 mg/kg followed by infusion of 1 mg x kg x hr. In addition, four healthy sheep, exposed to an intravenous infusion of endothelin-1 at 20 ng x kg x min, after 1 hr received tezosentan in stepwise increasing doses of 0.5, 1, and 2 mg x kg x hr that were maintained for 1 hr each. After a 4-hr recovery, the sheep received infusions of tezosentan at the same dose rates as a pretreatment to endothelin-1. MEASUREMENTS AND MAIN RESULTS In the sham-operated sheep, all cardiopulmonary variables remained unchanged. Lipopolysaccharide caused pulmonary hypertension, increased extravascular lung water index, and induced arterial hypoxemia. Tezosentan decreased the increments in pulmonary vascular resistance and extravascular lung water index by as much as 60% and 70%, respectively. In parallel, tezosentan ameliorated arterial hypoxemia, increased cardiac index, attenuated the decrease in stroke volume index, and reduced systemic vascular resistance. Compared with the lipopolysaccharide group, tezosentan further increased plasma concentrations of endothelin-1. In healthy animals, the administration of endothelin-1 induced systemic and pulmonary hypertension, increased extravascular lung water index, and evoked bradycardia and a decrease in cardiac index. These changes were attenuated by tezosentan infused at 1 and 2 mg x kg x hr. CONCLUSIONS In an ovine model of endotoxin-induced lung injury, tezosentan ameliorates pulmonary hypertension, lung edema, cardiac dysfunction, and arterial hypoxemia. Tezosentan counteracts the hemodynamic effects of endothelin-1 in a dose-dependent manner.
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Affiliation(s)
- Vladimir N Kuklin
- Departments of Anesthesiology, Faculty of Medicine, University of Tromsø, Norway.
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Kirov MY, Evgenov OV, Bjertnaes LJ. Combination of intravenously infused methylene blue and inhaled nitric oxide ameliorates endotoxin-induced lung injury in awake sheep. Crit Care Med 2003; 31:179-86. [PMID: 12545013 DOI: 10.1097/00003246-200301000-00028] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [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: 11/25/2022]
Abstract
OBJECTIVE To evaluate the effects of a combination of methylene blue, an inhibitor of the nitric oxide pathway, and inhaled nitric oxide on endotoxin-induced acute lung injury in awake sheep. DESIGN Prospective, randomized, controlled experimental study. SETTING University animal laboratory. SUBJECTS Twenty-four yearling, awake sheep. INTERVENTIONS The sheep were anesthetized and instrumented with vascular catheters. After 1 wk of recovery, the animals underwent tracheotomy and were subjected to intravenous infusions of endotoxin 10 ng x kg-1 x min-1 and isotonic saline 3 mL x kg-1 x hr-1 for 8 hrs. The sheep were randomly assigned to three groups of eight animals each: a) the control group received endotoxin and saline; b) the INO group received endotoxin, saline, and inhaled nitric oxide 40 ppm for 5 hrs; and c) the MB/INO group received endotoxin, saline, and methylene blue 3 mg/kg as an intravenous bolus injection followed by a continuous infusion of 3 mg x kg-1 x min-1 for 6 hrs in combination with inhaled nitric oxide 40 ppm for 5 hrs. MEASUREMENTS AND MAIN RESULTS Hemodynamic variables and blood gases were determined hourly. In the early phase of endotoxemia (0-2 hrs), methylene blue/inhaled nitric oxide reduced the increments in pulmonary arterial pressure, pulmonary microvascular pressure, and pulmonary vascular resistance index by 60% compared with the controls and to a greater extent than did inhaled nitric oxide alone. During the late phase, all the preceding variables returned closely to baseline following inhaled nitric oxide or methylene blue/inhaled nitric oxide but remained remarkably elevated in the control group. Inhaled nitric oxide and methylene blue/inhaled nitric oxide reduced the increase in extravascular lung water by 40% and 80%, respectively. Inhaled nitric oxide transiently attenuated the increase in venous admixture and did not prevent a decrease in arterial oxygenation. In the methylene blue/inhaled nitric oxide group, blood gases remained unchanged from baseline. CONCLUSIONS In sheep, methylene blue/inhaled nitric oxide protects more efficiently against acute lung injury than inhaled nitric oxide alone, as indicated by a milder pulmonary hypertension, less extravascular lung water accumulation, and maintained gas exchange.
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Affiliation(s)
- Mikhail Y Kirov
- Department of Anesthesiology, Faculty of Medicine, University of Tromsø, Norway
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