Association of Trauma Molecular Endotypes With Differential Response to Transfusion Resuscitation Strategies

Prehospital Post-Resuscitation Vital Sign Phenotypes are Associated with Outcomes Following Out-of-Hospital Cardiac Arrest

OBJECTIVES

The use of machine learning to identify patient 'clusters' using post-return of spontaneous circulation (ROSC) vital signs may facilitate the identification of patient subgroups at high risk of rearrest and mortality. Our objective was to use k-means clustering to identify post-ROSC vital sign clusters and determine whether these clusters were associated with rearrest and mortality.

METHODS

The ESO Data Collaborative 2018-2022 datasets were used for this study. We included adult, non-traumatic OHCA patients with >2 post-ROSC vital sign sets. Patients were excluded if they had an EMS-witnessed OHCA or were encountered during an interfacility transfer. Unsupervised (k-means) clustering was performed using minimum, maximum, and delta (last minus first) systolic blood pressure (BP), heart rate, SpO2, shock index, and pulse pressure. The assessed outcomes were mortality and rearrest. To explore the association between rearrest, mortality, and cluster, multivariable logistic regression modeling was used.

RESULTS

Within our cohort of 12,320 patients, five clusters were identified. Patients in cluster 1 were hypertensive, patients in cluster 2 were normotensive, patients in cluster 3 were hypotensive and tachycardic (n = 2164; 17.6%), patients in cluster 4 were hypoxemic and exhibited increasing systolic BP, and patients in cluster 5 were severely hypoxemic and exhibited a declining systolic BP. The overall proportion of patients who experienced mortality stratified by cluster was 63.4% (c1), 68.1% (c2), 78.8% (c3), 84.8% (c4), and 86.6% (c5). In comparison to the cluster with the lowest mortality (c1), each other cluster was associated with greater odds of mortality and rearrest.

CONCLUSIONS

Unsupervised k-means clustering yielded 5 post-ROSC vital sign clusters that were associated with rearrest and mortality.

Blood Transfusion for Major Trauma in Emergency Department

Severe bleeding is the leading cause of death in patients with major trauma admitted to the emergency department. It is estimated that about 50% of deaths happen within a few minutes of the traumatic event due to massive hemorrhage; 30% of deaths are related to neurological dysfunction and typically happen within two days of trauma; and approximately 20% of patients died of multiorgan failure and sepsis within days to weeks of the traumatic event. Over the past ten years, there has been an increased understanding of the underlying mechanisms and pathophysiology associated with traumatic bleeding leading to improved management measures. Traumatic events cause significant tissue damage, with the potential for severe blood loss and the release of cytokines and hormones. They are responsible for systemic inflammation, activation of fibrinolysis pathways, and consumption of coagulation factors. As the final results of this (more complex in real life) cascade, patients can develop tissue hypoxia, acidosis, hypothermia, and severe coagulopathy, resulting in a rapid deterioration of general conditions with a high risk of mortality. Prompt and appropriate management of massive bleeding and coagulopathy in patients with trauma remains a significant challenge for emergency physicians in their daily clinical practice. Our review aims to explore literature studies providing evidence on the treatment of hemorrhage with blood support in patients with trauma admitted to the Emergency Department with a high risk of death. Advances in blood transfusion protocols, along with improvements in other resuscitation strategies, have become one of the most important issues to face and a key topic of recent clinical research in this field.

Contemporary management of major haemorrhage in critical care

Haemorrhagic shock is frequent in critical care settings and responsible for a high mortality rate due to multiple organ dysfunction and coagulopathy. The management of critically ill patients with bleeding and shock is complex, and treatment of these patients must be rapid and definitive. The administration of large volumes of blood components leads to major physiological alterations which must be mitigated during and after bleeding. Early recognition of bleeding and coagulopathy, understanding the underlying pathophysiology related to specific disease states, and the development of individualised management protocols are important for optimal outcomes. This review describes the contemporary understanding of the pathophysiology of various types of coagulopathic bleeding; the diagnosis and management of critically ill bleeding patients, including major haemorrhage protocols and post-transfusion management; and finally highlights recent areas of opportunity to better understand optimal management strategies for managing bleeding in the intensive care unit (ICU).

Transforming research to improve therapies for trauma in the twenty-first century

Improvements have been made in optimizing initial care of trauma patients, both in prehospital systems as well as in the emergency department, and these have also favorably affected longer term outcomes. However, as specific treatments for bleeding are largely lacking, many patients continue to die from hemorrhage. Also, major knowledge gaps remain on the impact of tissue injury on the host immune and coagulation response, which hampers the development of interventions to treat or prevent organ failure, thrombosis, infections or other complications of trauma. Thereby, trauma remains a challenge for intensivists. This review describes the most pressing research questions in trauma, as well as new approaches to trauma research, with the aim to bring improved therapies to the bedside within the twenty-first century.

Commentary on gaps in prehospital trauma care: education and bioengineering innovations to improve outcomes in hemorrhage and traumatic brain injury

Hemorrhage remains the leading cause of preventable death on the battlefield and the civilian arena. Many of these deaths occur in the prehospital setting. Traumatic brain injury also represents a major source of early mortality and morbidity in military and civilian settings. The inaugural HERETIC (HEmostatic REsuscitation and Trauma Induced Coagulopathy) Symposium convened a multidisciplinary panel of experts in prehospital trauma care to discuss what education and bioengineering advancements in the prehospital space are necessary to improve outcomes in hemorrhagic shock and traumatic brain injury. The panel identified several promising technological breakthroughs, including field point-of-care diagnostics for hemorrhage and brain injury and unique hemorrhage control options for non-compressible torso hemorrhage. Many of these technologies exist but require further advancement to be feasibly and reliably deployed in a prehospital or combat environment. The panel discussed shifting educational and training paradigms to clinical immersion experiences, particularly for prehospital clinicians. The panel discussed an important balance between pushing traditionally hospital-based interventions into the field and developing novel intervention options specifically for the prehospital environment. Advancing prehospital diagnostics may be important not only to allow more targeted applications of therapeutic options, but also to identify patients with less urgent injuries that may not need more advanced diagnostics, interventions, or transfer to a higher level of care in resource-constrained environments. Academia and industry should partner and prioritize some of the promising advances identified with a goal to prepare them for clinical field deployment to optimize the care of patients near the point of injury.

Decreased Glycocalyx Shedding on Presentation in Hemorrhaging Geriatric Trauma Patients

INTRODUCTION

Plasma levels of syndecan-1 (Sdc-1), a biomarker of endothelial glycocalyx (EG) damage, correlate with worse outcomes in trauma patients. However, EG injury is not well characterized in injured older adults (OA). The aims of this study were to characterize Sdc-1 shedding in OA trauma patients relative to younger adults (YA) and determine associations with putative regulators of EG sheddases.

METHODS

We performed a secondary analysis of data from the Pragmatic, Randomized Optimal Platelet, and Plasma Ratios (PROPPR) trial, stratifying bluntly injured subjects into OA and YA groups based on upper age quartile (57 y). Plasma Sdc-1 levels were compared in OA and YA at hospital arrival through postinjury day 3, and the independent association between age and Sdc-1 level at arrival was determined after adjusting for differences in gender, shock index (SI), and pre-existing comorbidities. In a follow-up analysis, case-control matching was used to create populations of OA and YA with equivalent SI and injury severity score. Levels of Sdc-1 were compared between these matched groups, and the relationships with candidate regulators of EG shedding were assessed.

RESULTS

Of 680 subjects in the Pragmatic, Randomized Optimal Platelet, and Plasma Ratios trial, 350 (51%) had blunt injuries, and 92 (26.3%) of these were OA. Plasma Sdc-1 levels at arrival, 2 h, and 6 h were significantly lower in OA compared to YA (all P < 0.05). After adjusting for sex, pre-existing morbidities and SI, age was associated with decreased Sdc-1 levels at arrival. In the matched analyses, Sdc-1, high-mobility group box 1 and tissue inhibitor of metalloproteinase-2 levels were lower in OA compared to YA. Both high-mobility group box-1 and tissue inhibitor of metalloproteinase-2 significantly correlated with arrival Sdc-1 and were inversely associated with age.

CONCLUSIONS

This study indicates that increased age is independently associated with decreased Sdc-1 levels among patients with blunt injuries. Suppressed plasma levels of sheddases in relation to diminished Sdc-1 shedding suggest that mechanisms regulating EG cleavage may be impaired in injured older adults. These findings provide novel insight into the age-dependent impact of injury on the vascular endothelium, which could have important implications for the clinical management of older adults following trauma.

Point-of-care, goal-directed management of bleeding in trauma patients

PURPOSE OF REVIEW

The purpose of this review is to consider the clinical value of point-of-care (POC) testing in coagulopathic trauma patients with traumatic brain injury (TBI) and trauma-induced coagulopathy (TIC).

RECENT FINDINGS

Patients suffering from severe TBI or TIC are at risk of developing pronounced haemostatic disorders. Standard coagulation tests (SCTs) are insufficient to reflect the complexity of these coagulopathies. Recent evidence has shown that viscoelastic tests (VETs) identify haemostatic disorders more rapidly and in more detail than SCTs. Moreover, VET results can guide coagulation therapy, allowing individualised treatment, which decreases transfusion requirements. However, the impact of VET on mortality remains uncertain. In contrast to VETs, the clinical impact of POC platelet function testing is still unproven.

SUMMARY

POC SCTs are not able to characterise the complexity of trauma-associated coagulopathy. VETs provide a rapid estimation of underlying haemostatic disorders, thereby providing guidance for haemostatic therapy, which impacts allogenic blood transfusion requirements. The value of POC platelet function testing to identify platelet dysfunction and guide platelet transfusion is still uncertain.

Trans-Omics analysis of post injury thrombo-inflammation identifies endotypes and trajectories in trauma patients

Understanding and managing the complexity of trauma-induced thrombo-inflammation necessitates an innovative, data-driven approach. This study leveraged a trans-omics analysis of longitudinal samples from trauma patients to illuminate molecular endotypes and trajectories that underpin patient outcomes, transcending traditional demographic and physiological characterizations. We hypothesize that trans-omics profiling reveals underlying clinical differences in severely injured patients that may present with similar clinical characteristics but ultimately have very different responses to treatment and clinical outcomes. Here we used proteomics and metabolomics to profile 759 of longitudinal plasma samples from 118 patients at 11 time points and 97 control subjects. Results were used to define distinct patient states through data reduction techniques. The patient groups were stratified based on their shock severity and injury severity score, revealing a spectrum of responses to trauma and treatment that are fundamentally tied to their unique underlying biology. Ensemble models were then employed, demonstrating the predictive power of these molecular signatures with area under the receiver operating curves of 80 to 94% for key outcomes such as INR, ICU-free days, ventilator-free days, acute lung injury, massive transfusion, and death. The molecularly defined endotypes and trajectories provide an unprecedented lens to understand and potentially guide trauma patient management, opening a path towards precision medicine. This strategy presents a transformative framework that aligns with our understanding that trauma patients, despite similar clinical presentations, might harbor vastly different biological responses and outcomes.