TRAUMA INDUCES INTRAVASCULAR HEMOLYSIS, EXACERBATED BY RED BLOOD CELL TRANSFUSION AND ASSOCIATED WITH DISRUPTED ARGININE-NITRIC OXIDE METABOLISM

Role of adenosine A3 receptor and endothelial nitric oxide synthase in patients with traumatic hemorrhagic shock

BACKGROUND

The aim of this research is to access the expression of adenosine A3 receptor (ADORA3) and nitric oxide synthase 3 (NOS3) genes and serum levels of ADORA3 and NOS3 in patients with multiple trauma with hemorrhagic shock.

MATERIALS AND METHODS

The study was performed at Erciyes University between November 2022 and March 2024, in a prospective and controlled manner. Patients diagnosed with traumatic hemorrhagic shock and requiring transfusion in the emergency department were selected as the patients group. Gene expressions were analyzed using quantitative real-time PCR analysis in total RNA samples and serum levels of NOS3 and ADORA3 were detected using ELISA measurements.

RESULTS

In patients with multiple trauma, adenosine A3 receptor (ADORA3) gene expression showed a significant increase at discharge when compared to healthy controls (P < 0.05). However, serum levels of ADORA3 showed significant decreases at all stages (i.e. at admission, at 24 h, and at discharge) of patients. Although no significant changes were detected in NOS3 gene expression, marked decreases in serum NOS3 levels were observed at admission and at 24 h in multiple trauma patients (P < 0.05). ADORA3 and NOS3 gene expressions were found to be significantly diminished in nonsurvivors.

CONCLUSION

The study emphasizes the importance of ADORA3 and NOS3 gene expressions in influencing shock progression in multiple trauma patients. The increase in ADORA3 gene expression may play a role in restoring vascular reactivity after traumatic shock. Decreased serum NOS3 and ADORA3 levels can contribute to the shock progression in the pathophysiology of multiple trauma.

Influence of hemolysis, lipemia and bilirubin on biobank sample quality- origin and interference in the use for extracellular vesicle (EV) and MiRNA analyses

PURPOSE

Pre-analytic interferences can influence the laboratory downstream measurements. We recognized hemolysis, lipemia and bilirubin in some of the serum/plasma samples of the NTF-Biobank from polytraumatized patients. Aim of the present study was to detect interferences, find reasons and describe the influence on downstream analyses.

METHODS

The study included serum samples of n = 88 polytraumatized patients admitted to a Level 1 Trauma Center in Germany at the ER & up to 10 days after trauma. Optical absorption spectra of UV-VIS (350-660 nm) were measured to detect hemolysis, lipemia and bilirubin. To find reasons for the interferences, clinical parameters like triglycerides (TAGs), nutrition, anaesthesia or transfusions were collected from patients' record. Extracellular vesicles (EVs) were isolated by SEC from controls, lipidemic and hemolytic samples and analysed via NTA.

RESULTS

Within 10 days after trauma 31.8% of polytraumatized patients' samples showed hemolysis, 12.5% showed increased bilirubin and 15.9% lipemia. Hemolysis occurred in samples mostly at the ER (18%) and was not associated with the number of red blood cell transfusions or the ISS. Both contaminants, hemolysis and lipemia interfered with EV/EV-miRNA measurements. EV miR-16-5p was significantly increased in patients with hemolysis. The presence of lipids further influenced the EV particle size distribution and concentration.

CONCLUSION

The optical absorption spectra measurement is an easy tool for a robust pre-analytic sample controlling for the presence of interferences. Nutrition and anaesthesia were found to be related with lipemia in samples. Hemolysis and lipemia interfered with EV/EV-miRNA analysis. Therefore, the optical absorption spectra pre-analyses should be incorporated in the EV-biobank sampling.

Elevated cell-free hemoglobin: A novel early biomarker following traumatic injury

BACKGROUND

Cell-free hemoglobin (CFH) and free heme are potent mediators of endotheliopathy and organ injury in sepsis, but their roles in other hemolytic pathologies are not well-defined. A prime example is trauma where early hemolysis may initiate damage and predict outcome. Here, we investigated the presence of plasma CFH, heme, and their major scavengers after traumatic injury.

METHODS

Adult patients who presented as highest-level activations were prospectively enrolled at a level 1 trauma center between 2021 and 2023. Venous blood was collected upon arrival (pretransfusion) and 6, 12, and 24 hours after admittance for quantification of CFH, haptoglobin, heme, and hemopexin.

RESULTS

We studied 119 mostly male subjects (101:18) with a median age of 48 years (interquartile range [IQR], 31-64 years) and an Injury Severity Score of 22 (IQR, 11-29); the majority had suffered blunt force trauma. The 28-day mortality rate was 11%. Cell-free hemoglobin was high upon emergency department arrival (10.9 μM; IQR, 6.8-17.6) and then declined but remained elevated compared with normative levels during the monitoring period (>5 vs. ~0.2 μM). The initial drop in CFH was attributed to haptoglobin binding and clearance. Notably, there was a subgroup of patients with two- to threefold higher levels of CFH on emergency department arrival (median, 25 μM). Patients with these highest CFH levels had longer hospital stays and more frequent complications.

CONCLUSION

Cell-free hemoglobin is elevated in trauma patients very early after injury and may impact outcome. While further work is needed, early correction of hemolysis could provide benefit.

LEVEL OF EVIDENCE

Prognostic/Epidemiological Study; Level III.

Platelet releasates mitigate the endotheliopathy of trauma

BACKGROUND

Platelets are well known for their roles in hemostasis, but they also play a key role in thromboinflammatory pathways by regulating endothelial health, stimulating angiogenesis, and mediating host defense through both contact dependent and independent signaling. When activated, platelets degranulate releasing multiple active substances. We hypothesized that the soluble environment formed by trauma platelet releasates (TPR) attenuates thromboinflammation via mitigation of trauma induced endothelial permeability and metabolomic reprogramming.

METHODS

Blood was collected from injured and healthy patients to generate platelet releasates and plasma in parallel. Permeability of endothelial cells when exposed to TPR and plasma (TP) was assessed via resistance measurement by electric cell-substrate impedance sensing (ECIS). Endothelial cells treated with TPR and TP were subjected to mass spectrometry-based metabolomics.

RESULTS

TP increased endothelial permeability, whereas TPR decreased endothelial permeability when compared with untreated cells. When TP and TPR were mixed ex vivo, TPR mitigated TP-induced permeability, with significant increase in AUC compared with TP alone. Metabolomics of TPR and TP demonstrated disrupted redox reactions and anti-inflammatory mechanisms.

CONCLUSION

Trauma platelet releasates provide endothelial barrier protection against TP-induced endothelial permeability. Our findings highlight a potential beneficial action of activated platelets on the endothelium in injured patients through disrupted redox reactions and increased antioxidants. Our findings support that soluble signaling from platelet degranulation may mitigate the endotheliopathy of trauma. The clinical implications of this are that activated platelets may prove a promising therapeutic target in the complex integration of thrombosis, endotheliopathy, and inflammation in trauma.

THE IMPACT OF SCHISTOCYTE DETECTION ON MORTALITY AND ORGAN FAILURE IN PATIENTS WITH SEPSIS

ABSTRACT

Purpose : This study aimed to investigate the presence of schistocytes in patients with sepsis and its association with mortality and organ failure. Methods : We conducted a retrospective observational study at Shiga University of Medical Science Hospital, Japan, from January 2015 to April 2021. This study included patients diagnosed with sepsis or septic shock. Schistocytes were identified through daily hematological examinations. Moreover, data on mortality rates and organ failure based on Sequential Organ Failure Assessment scores were systematically collected and analyzed. Results : Schistocytes were detected in 41 of the 330 patients with sepsis. The presence of schistocytes was associated with significantly high 90-day and 1-year mortality rates (48.7% and 68.2%, respectively; P < 0.001). Patients with schistocytes exhibited higher Sequential Organ Failure Assessment scores, particularly in the coagulation and renal components, indicating more severe organ failure than that observed in patients without schistocytes. These findings persisted even after adjusting for confounding factors, such as age, sex, and baseline comorbidities. Additionally, we observed that patients with schistocytes required frequent red blood cells, further highlighting the severity of their conditions. Conclusion : Schistocytes are significantly associated with increased long-term mortality and organ failure in patients with sepsis. Their detection may provide crucial insights into disease severity, guide targeted therapeutic strategies, and potentially improve the long-term outcomes of sepsis management.

RESUSCITATIVE ENDOVASCULAR BALLOON OCCLUSION OF THE AORTA: ZONE 1 REPERFUSION-INDUCED COAGULOPATHY

ABSTRACT

Objective: We sought to identify potential drivers behind resuscitative endovascular balloon occlusion of the aorta (REBOA) induced reperfusion coagulopathy using novel proteomic methods. Background: Coagulopathy associated with REBOA is poorly defined. The REBOA Zone 1 provokes hepatic and intestinal ischemia that may alter coagulation factor production and lead to molecular pathway alterations that compromises hemostasis. We hypothesized that REBOA Zone 1 would lead to reperfusion coagulopathy driven by mediators of fibrinolysis, loss of coagulation factors, and potential endothelial dysfunction. Methods: Yorkshire swine were subjected to a polytrauma injury (blast traumatic brain injury, tissue injury, and hemorrhagic shock). Pigs were randomized to observation only (controls, n = 6) or to 30 min of REBOA Zone 1 (n = 6) or REBOA Zone 3 (n = 4) as part of their resuscitation. Thromboelastography was used to detect coagulopathy. ELISA assays and mass spectrometry proteomics were used to measure plasma protein levels related to coagulation and systemic inflammation. Results: After the polytrauma phase, balloon deflation of REBOA Zone 1 was associated with significant hyperfibrinolysis (TEG results: REBOA Zone 1 35.50% versus control 9.5% vs. Zone 3 2.4%, P < 0.05). In the proteomics and ELISA results, REBOA Zone 1 was associated with significant decreases in coagulation factor XI and coagulation factor II, and significant elevations of active tissue plasminogen activator, plasmin-antiplasmin complex complexes, and syndecan-1 (P < 0.05). Conclusion: REBOA Zone 1 alters circulating mediators of clot formation, clot lysis, and increases plasma levels of known markers of endotheliopathy, leading to a reperfusion-induced coagulopathy compared with REBOA Zone 3 and no REBOA.

Cell-Free Hemoglobin in the Pathophysiology of Trauma: A Scoping Review

OBJECTIVES

Cell-free hemoglobin (CFH) is a potent mediator of endothelial dysfunction, organ injury, coagulopathy, and immunomodulation in hemolysis. These mechanisms have been demonstrated in patients with sepsis, hemoglobinopathies, and those receiving transfusions. However, less is known about the role of CFH in the pathophysiology of trauma, despite the release of equivalent levels of free hemoglobin.

DATA SOURCES

Ovid MEDLINE, Embase, Web of Science Core Collection, and BIOSIS Previews were searched up to January 21, 2023, using key terms related to free hemoglobin and trauma.

DATA EXTRACTION

Two independent reviewers selected studies focused on hemolysis in trauma patients, hemoglobin breakdown products, hemoglobin-mediated injury in trauma, transfusion, sepsis, or therapeutics.

DATA SYNTHESIS

Data from the selected studies and their references were synthesized into a narrative review.

CONCLUSIONS

Free hemoglobin likely plays a role in endothelial dysfunction, organ injury, coagulopathy, and immune dysfunction in polytrauma. This is a compelling area of investigation as multiple existing therapeutics effectively block these pathways.

The proteomic and metabolomic signatures of isolated and polytrauma traumatic brain injury

BACKGROUND

The interactions of polytrauma, shock, and traumatic brain injury (TBI) on thromboinflammatory responses remain unclear and warrant investigation as we strive towards personalized medicine in trauma. We hypothesized that comprehensive omics characterization of plasma would identify unique metabolic and thromboinflammatory pathways following TBI.

METHODS

Patients were categorized as TBI vs Non-TBI, and stratified into Polytrauma or minimally injured. Discovery 'omics was employed to quantify the top differently expressed proteins and metabolites of TBI and Non-TBI patient groups.

RESULTS

TBI compared to Non-TBI showed gene enrichment in coagulation/complement cascades and neuronal markers. TBI was associated with elevation in glycolytic metabolites and conjugated bile acids. Division into isolated TBI vs polytrauma showed further distinction of proteomic and metabolomic signatures.

CONCLUSION

Identified mediators involving in neural inflammation, blood brain barrier disruption, and bile acid building leading to TBI associated coagulopathy offer suggestions for follow up mechanistic studies to target personalized interventions.

Iron Deposition in the Bone Marrow and Spleen of Nonhuman Primates with Acute Radiation Syndrome

The risk of exposure to high levels of ionizing radiation from nuclear weapons or radiological accidents is an increasing world concern. Partial- or total-body exposure to high doses of radiation is potentially lethal through the induction of acute radiation syndrome (ARS). Hematopoietic cells are sensitive to radiation exposure; white blood cells primarily undergo apoptosis while red blood cells (RBCs) undergo hemolysis. Several laboratories demonstrated that the rapid hemolysis of RBCs results in the release of acellular iron into the blood. We recently demonstrated using a murine model of ARS after total-body irradiation (TBI) and the loss of RBCs, iron accumulated in the bone marrow and spleen, notably between 4-21 days postirradiation. Here, we investigated iron accumulation in the bone marrow and spleens from TBI nonhuman primates (NHPs) using histological stains. We observed trends in increased intracellular and extracellular brown pigmentation in the bone marrow after various doses of radiation, especially after 4-15 days postirradiation, but these differences did not reach significance. We observed a significant increase in Prussian blue-staining intracellular iron deposition in the spleen 13-15 days after 5.8-8.5 Gy of TBI. We observed trends of increased iron in the spleen after 30-60 days postirradiation, with varying doses of radiation, but these differences did not reach significance. The NHP model of ARS confirms our earlier findings in the murine model, showing iron deposition in the bone marrow and spleen after TBI.

A metabolomic and proteomic analysis of pathologic hypercoagulability in traumatic brain injury patients after dura violation

BACKGROUND

The coagulopathy of traumatic brain injury (TBI) remains poorly understood. Contradictory descriptions highlight the distinction between systemic and local coagulation, with descriptions of systemic hypercoagulability despite intracranial hypocoagulopathy. This perplexing coagulation profile has been hypothesized to be due to tissue factor release. The objective of this study was to assess the coagulation profile of TBI patients undergoing neurosurgical procedures. We hypothesize that dura violation is associated with higher tissue factor and conversion to a hypercoagulable profile and unique metabolomic and proteomic phenotype.

METHODS

This is a prospective, observational cohort study of all adult TBI patients at an urban, Level I trauma center who underwent a neurosurgical procedure from 2019 to 2021. Whole blood samples were collected before and then 1 hour following dura violation. Citrated rapid and tissue plasminogen activator (tPA) thrombelastography (TEG) were performed, in addition to measurement of tissue factory activity, metabolomics, and proteomics.

RESULTS

Overall, 57 patients were included. The majority (61%) were male, the median age was 52 years, 70% presented after blunt trauma, and the median Glasgow Coma Score was 7. Compared with pre-dura violation, post-dura violation blood demonstrated systemic hypercoagulability, with a significant increase in clot strength (maximum amplitude of 74.4 mm vs. 63.5 mm; p < 0.0001) and a significant decrease in fibrinolysis (LY30 on tPAchallenged TEG of 1.4% vs. 2.6%; p = 0.04). There were no statistically significant differences in tissue factor. Metabolomics revealed notable increases in metabolites involved in late glycolysis, cysteine, and one-carbon metabolites, and metabolites involved in endothelial dysfunction/arginine metabolism/responses to hypoxia. Proteomics revealed notable increase in proteins related to platelet activation and fibrinolysis inhibition.

CONCLUSION

A systemic hypercoagulability is observed in TBI patients, characterized by increased clot strength and decreased fibrinolysis and a unique metabolomic and proteomics phenotype independent of tissue factor levels.

Omics markers of platelet transfusion in trauma patients

BACKGROUND

Even in the era of the COVID-19 pandemic, trauma remains the global leading cause of mortality under the age of 49. Trauma-induced coagulopathy is a leading driver of early mortality in critically ill patients, and transfusion of platelet products is a life-saving intervention to restore hemostasis in the bleeding patient. However, despite extensive functional studies based on viscoelastic assays, limited information is available about the impact of platelet transfusion on the circulating molecular signatures in trauma patients receiving platelet transfusion.

MATERIALS AND METHODS

To bridge this gap, we leveraged metabolomics and proteomics approaches to characterize longitudinal plasma samples (n = 118; up to 11 time points; total samples: 759) from trauma patients enrolled in the Control Of Major Bleeding After Trauma (COMBAT) study. Samples were collected in the field, in the emergency department (ED), and at intervals up to 168 h (7 days) post-hospitalization. Transfusion of platelet (PLT) products was performed (n = 30; total samples: 250) in the ED through 24 h post-hospitalization. Longitudinal plasma samples were subjected to mass spectrometry-based metabolomics and proteomics workflows. Multivariate analyses were performed to determine omics markers of transfusion of one, two, three, or more PLT transfusions.

RESULTS

Higher levels of tranexamic acid (TXA), inflammatory proteins, carnitines, and polyamines were detected in patients requiring PLT transfusion. Correlation of PLT units with omics data suggested sicker patients required more units and partially overlap with the population requiring transfusion of packed red blood cell products. Furthermore, platelet activation was likely increased in the most severely injured patients. Fatty acid levels were significantly lower in PLT transfusion recipients (at time of maximal transfusion: Hour 4) compared with non-recipients, while carnitine levels were significantly higher. Fatty acid levels restore later in the time course (e.g., post-PLT transfusion).

DISCUSSION

The present study provides the first multi-omics characterization of platelet transfusion efficacy in a clinically relevant cohort of trauma patients. Physiological alterations following transfusion were detected, highlighting the efficacy of mass spectrometry-based omics techniques to improve personalized transfusion medicine. More specialized clinical research studies focused on PLT transfusion, including organized pre and post transfusion sample collection and limitation to PLT products only, are required to fully understand subsequent metabolomic and proteomic alterations.