Damage control resuscitation is associated with a reduction in resuscitation volumes and improvement in survival in 390 damage control laparotomy patients. Ann Surg. 2011;254:598-605. [PMID: 21918426 DOI: 10.1097/sla.0b013e318230089e]

Survey of pediatric massive transfusion protocol practice at United States level I trauma centers: An AABB Pediatric Transfusion Medicine Subsection study

BACKGROUND

Trauma remains the leading cause of pediatric mortality in the United States. Although use of massive transfusion protocols (MTPs) in this population is widespread, optimal pediatric resuscitation is not well established. We sought to assess contemporary pediatric MTP practice in the United States.

STUDY DESIGN AND METHODS

A web-based survey was designed by the Association for the Advancement of Blood & Biotherapies (AABB) Pediatric Transfusion Medicine Subsection and distributed to select American College of Surgeons (ACS) Level I Verified pediatric trauma centers. The survey assessed current MTP policy, implementation, and recent changes in practice.

RESULTS

Response rate was 55% (22/40). Almost half of the respondents were from the South. The median RBC:plasma ratio was 1 (interquartile range 1-1.5). Protocolized fibrinogen supplementation was common while integration of antifibrinolytic therapy into MTPs was infrequent. Viscoelastic testing (VET) was available at most sites, 71% (15/21, one site did not respond), and was generally utilized on an ad-hoc basis. Roughly, a third of sites had changed their MTP in the past 3 years due to blood supply issues, and about a third reported having group O Whole Blood on-site.

CONCLUSION

MTP practice is similar throughout the United States. Though fibrinogen supplementation is common-other emerging interventions such as antifibrinolytic therapy or utilization of routine viscoelastic testing-are not widespread. Pediatric transfusion medicine experts must continue to follow practice change, as contemporary large trials begin to characterize new supportive modalities to optimize resuscitation in pediatric trauma patients.

Machine learning models predict triage levels, massive transfusion protocol activation, and mortality in trauma utilizing patients hemodynamics on admission

BACKGROUND

The effective management of trauma patients necessitates efficient triaging, timely activation of Massive Blood Transfusion Protocols (MTP), and accurate prediction of in-hospital outcomes. Machine learning (ML) algorithms have emerged as up-and-coming tools in the domains of optimizing triage decisions, improving intervention strategies, and predicting clinical outcomes, consistently outperforming traditional methodologies. This study aimed to develop, assess, and compare several ML models for the triaging processes, activation of MTP, and mortality prediction.

METHODS

In a 10-year retrospective study, the predictive capabilities of seven ML models for trauma patients were systematically assessed using on-admission patients' hemodynamic data. All patient's data were randomly divided into training (80 %) and test (20 %) sets. Employing Python for data preprocessing, feature scaling, and model development, we evaluated K-Nearest Neighbors (KNN), Logistic Regression (LR), Decision Tree (DT), Support Vector Machines (SVM) with RBF kernels, Random Forest (RF), Extreme Gradient Boosting (XGBoost), and Artificial Neural Network (ANN). We employed various imputation techniques and addressed data imbalance through down-sampling, up-sampling, and synthetic minority for the over-sampling technique (SMOTE). Hyperparameter tuning, coupled with 5-fold cross-validation, was performed. The evaluation included essential metrics like sensitivity, specificity, F1 score, accuracy, Area Under the Receiver Operating Curve (AUC ROC), and Area Under the Precision recall Curve (AUC PR), ensuring robust predictive capability.

RESULT

This study included 17,390 adult trauma patients; of them, 19.5 % (3385) were triaged at a critical level, 3.8 % (664) required MTP, and 7.7 % (1335) died in the hospital. The model's performance improved using imputation and balancing techniques. The overall models demonstrated notable performance metrics for predicting triage, MTP activation, and mortality with F1 scores of 0.75, 0.42, and 0.79, sensitivities of 0.73, 0.82, and 0.9, and AUC ROC values of 0.89, 0.95 and 0.99 respectively.

CONCLUSION

Machine learning, especially RF models, effectively predicted trauma triage, MTP activation, and mortality. Featured critical hemodynamic variables include shock indices, systolic blood pressure, and mean arterial pressure. Therefore, models can do better than individual parameters for the early management and disposition of patients in the ED. Future research should focus on creating sensitive and interpretable models to enhance trauma care.

Pre-Injury Statin Exposure is Associated With Improved Outcomes in Injured Patients That Receive Whole Blood

Introduction: Whole blood (WB) is associated with improved mortality while lowering blood product utilization. Furthermore, statin medications are associated with favorable outcomes in traumatic brain injury and risk reduction of venous thromboembolism. However, the use of statin medications has not been evaluated in those receiving WB. The objective of this study is to determine the effects of pre-injury statin exposure on patients receiving WB.Methods: Patients that underwent WB first resuscitation and received pre-injury statins were compared to those that did not receive pre-injury statins. Demographics as well as complication rates, blood product transfusion volumes, and mortality were evaluated. Univariate and multivariable analyses were used to determine independent predictors of mortality.Results: In the study period, 785 patients received WB as part of their resuscitation. One hundred and thirty five patients (17.3%) took statin medications prior to injury. Patients that were exposed to a pre-injury statin had a lower mortality rate than those that were not exposed (21.5% vs 32.5%, P = .01). After adjusting for imbalances, age, ISS, Glasgow Coma Scale, admission systolic blood pressures, and pre-injury statin use were independent predictors of mortality following multiple logistic regression. When evaluating outcomes based on statin intensity, the use of high-intensity statins was associated with lower mortality (OR: .37, 95% CI: .13-.93), whereas moderate and low-intensity statins were not.Conclusion: In patients resuscitated with WB, pre-injury statins use was associated with improved outcomes. Specifically, patients that received high-intensity pre-injury statins appeared to be the population that benefited.

Effective approaches to address noncompressible torso hemorrhage

PURPOSE OF REVIEW

Noncompressible torso hemorrhage (NCTH) is now considered as the major cause of preventable death after both severe military and civilian trauma. Around 20% of all trauma patients still die from uncontrolled exsanguination along with rapidly evolving hemostatic failure. This review highlights the most recent advances in the field and provides an outline for future research directions.

RECENT FINDINGS

The updated definition of NCTH includes a combination of high-grade anatomical torso injury, hemodynamic instability, urgent need for hemorrhage control and aggressive hemostatic resuscitation. Therapeutic concepts consider the following three aspects: control the bleeding source (close the tap), resuscitate to maintain organ perfusion and restore hemostasis (fill the tank), and increase the body's resistance against ischemia (upgrade the armor).

SUMMARY

The concepts for the early management of NCTH have substantially evolved over the last decade. The development of new devices and techniques combined with early intervention of hemostatic failure have contributed to more successful resuscitations. Future research needs to refine and validate their potential clinical application.

Mortality in hypotensive combat casualties who require emergent laparotomy in the forward deployed environment

INTRODUCTION

Mortality rates among hypotensive civilian patients requiring emergent laparotomy exceed 40%. Damage control (DCR) principles were incorporated into the military's Clinical Practice Guidelines (CPG) in 2008. We examined combat casualties requiring emergent laparotomy to characterize how mortality rates compare to hypotensive civilian trauma patients.

METHODS

The DoD Trauma Registry (2004-2020) was queried for adults who underwent combat laparotomy. Patients who were hypotensive were compared to normotensive patients. Mortality was the outcome of interest. Mortality rates before (2004-2007) and after (2009-2020) DCR CPG implementation were analyzed.

RESULTS

1051 patients were studied. Overall mortality was 6.5% for normotensive casualties and 28.7% for hypotensive casualties. Mortality decreased in normotensive patients but remained unchanged in hypotensive patients following the implementation of the DCR CPG.

CONCLUSION

Hypotensive combat casualties undergoing emergent laparotomy demonstrated a mortality rate of 29.5%. Despite many advances, mortality rates remain high in hypotensive patients requiring emergent laparotomy.

Evaluating patient factors, operative management and postoperative outcomes in trauma laparotomy patients worldwide: a protocol for a global observational multicentre trauma study

INTRODUCTION

Trauma contributes to the greatest loss of disability-adjusted life-years for adolescents and young adults worldwide. In the context of global abdominal trauma, the trauma laparotomy is the most commonly performed operation. Variation likely exists in how these patients are managed and their subsequent outcomes, yet very little global data on the topic currently exists. The objective of the GOAL-Trauma study is to evaluate both patient and injury factors for those undergoing trauma laparotomy, their clinical management and postoperative outcomes.

METHODS

We describe a planned prospective multicentre observational cohort study of patients undergoing trauma laparotomy. We will include patients of all ages who present to hospital with a blunt or penetrating injury and undergo a trauma laparotomy within 5 days of presentation to the treating centre. The study will collect system, patient, process and outcome data, following patients up until 30 days postoperatively (or until discharge or death, whichever is first). Our sample size calculation suggests we will need to recruit 552 patients from approximately 150 recruiting centres.

DISCUSSION

The GOAL-Trauma study will provide a global snapshot of the current management and outcomes for patients undergoing a trauma laparotomy. It will also provide insight into the variation seen in the time delays for receiving care, the disease and patient factors present, and patient outcomes. For current standards of trauma care to be improved worldwide, a greater understanding of the current state of trauma laparotomy care is paramount if appropriate interventions and targets are to be identified and implemented.

Hypertension during transfer is associated with poor outcomes in unstable patients with ruptured abdominal aortic aneurysm

OBJECTIVE

Limited data exist for optimal blood pressure (BP) management during transfer of patients with ruptured abdominal aortic aneurysm (rAAA). This study evaluates the effects of hypertension and severe hypotension during interhospital transfers in a cohort of patients with rAAA in hemorrhagic shock.

METHODS

We performed a retrospective, single-institution review of patients with rAAA transferred via air ambulance to a quaternary referral center for repair (2003-2019). Vitals were recorded every 5 minutes in transit. Hypertension was defined as a systolic BP of ≥140 mm Hg. The primary cohort included patients with rAAA with hemorrhagic shock (≥1 episode of a systolic BP of <90 mm Hg) during transfer. The primary analysis compared those who experienced any hypertensive episode to those who did not. A secondary analysis evaluated those with either hypertension or severe hypotension <70 mm Hg. The primary outcome was 30-day mortality.

RESULTS

Detailed BP data were available for 271 patients, of which 125 (46.1%) had evidence of hemorrhagic shock. The mean age was 74.2 ± 9.1 years, 93 (74.4%) were male, and the median total transport time from helicopter dispatch to arrival at the treatment facility was 65 minutes (interquartile range, 46-79 minutes). Among the cohort with shock, 26.4% (n = 33) had at least one episode of hypertension. There were no significant differences in age, sex, comorbidities, AAA repair type, AAA anatomic location, fluid resuscitation volume, blood transfusion volume, or vasopressor administration between the hypertensive and nonhypertensive groups. Patients with hypertension more frequently received prehospital antihypertensives (15% vs 2%; P = .01) and pain medication (64% vs 24%; P < .001), and had longer transit times (36.3 minutes vs 26.0 minutes; P = .006). Episodes of hypertension were associated with significantly increased 30-day mortality on multivariable logistic regression (adjusted odds ratio [aOR], 4.71; 95% confidence interval [CI], 1.54-14.39; P = .007; 59.4% [n = 19] vs 40.2% [n = 37]; P = .01). Severe hypotension (46%; n = 57) was also associated with higher 30-day mortality (aOR, 2.82; 95% CI, 1.27-6.28; P = .01; 60% [n = 34] vs 32% [n = 22]; P = .01). Those with either hypertension or severe hypotension (54%; n = 66) also had an increased odds of mortality (aOR, 2.95; 95% CI, 1.08-8.11; P = .04; 58% [n = 38] vs 31% [n = 18]; P < .01). Level of hypertension, BP fluctuation, and timing of hypertension were not significantly associated with mortality.

CONCLUSIONS

Hypertensive and severely hypotensive episodes during interhospital transfer were independently associated with increased 30-day mortality in patients with rAAA with shock. Hypertension should be avoided in these patients, but permissive hypotension approaches should also maintain systolic BPs above 70 mm Hg whenever possible.

Prehospital tranexamic acid is associated with a survival benefit without an increase in complications: results of two harmonized randomized clinical trials

INTRODUCTION

Recent randomized clinical trials have demonstrated that prehospital tranexamic acid (TXA) administration following injury is safe and improves survival. However, the effect of prehospital TXA on adverse events, transfusion requirements and any dose response relationships require further elucidation.

METHODS

A secondary analysis was performed using harmonized data from two large, double-blinded, randomized prehospital TXA trials. Outcomes, including 28-day mortality, pertinent adverse events and 24-hour red cell transfusion requirements were compared between TXA and placebo groups. Regression analyses were utilized to determine the independent associations of TXA after adjusting for study enrollment, injury characteristics and shock severity across a broad spectrum of injured patients. Dose response relationships were similarly characterized based upon grams of prehospital TXA administered.

RESULTS

A total of 1744 patients had data available for secondary analysis and were included in the current harmonized secondary analysis. The study cohort had an overall mortality of 11.2% and a median injury severity score of 16 (IQR: 5-26). TXA was independently associated with a lower risk of 28-day mortality (HR: 0.72, 95% CI 0.54, 0.96, p = 0.03). Prehospital TXA also demonstrated an independent 22% lower risk of mortality for every gram of prehospital TXA administered (HR: 0.78, 95% CI 0.63, 0.96, p = 0.02). Multivariable linear regression verified that patients who received TXA were independently associated with lower 24-hour red cell transfusion requirements (β: -0.31, 95% CI -0.61, -0.01, p = 0.04) with a dose-response relationship (β: -0.24, 95% CI -0.45, -0.02, p = 0.03). There was no independent association of prehospital TXA administration on VTE, seizure, or stroke.

CONCLUSIONS

In this secondary analysis of harmonized data from two large randomized interventional trials, prehospital TXA administration across a broad spectrum of injured patients is safe. Prehospital TXA is associated with a significant 28-day survival benefit, lower red cell transfusion requirements at 24 hours and demonstrates a dose-response relationship.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level III.

Blood failure: traumatic hemorrhage and the interconnections between oxygen debt, endotheliopathy, and coagulopathy

This review explores the concept of "blood failure" in traumatic injury, which arises from the interplay of oxygen debt, the endotheliopathy of trauma (EoT), and acute traumatic coagulopathy (ATC). Traumatic hemorrhage leads to the accumulation of oxygen debt, which can further exacerbate hemorrhage by triggering a cascade of events when severe. Such events include EoT, characterized by endothelial glycocalyx damage, and ATC, involving platelet dysfunction, fibrinogen depletion, and dysregulated fibrinolysis. To manage blood failure effectively, a multifaceted approach is crucial. Damage control resuscitation strategies such as use of permissive hypotension, early hemorrhage control, and aggressive transfusion of blood products including whole blood aim to minimize oxygen debt and promote its repayment while addressing endothelial damage and coagulation. Transfusions of red blood cells, plasma, and platelets, as well as the use of tranexamic acid, play key roles in hemostasis and countering ATC. Whole blood, whether fresh or cold-stored, is emerging as a promising option to address multiple needs in traumatic hemorrhage. This review underscores the intricate relationships between oxygen debt, EoT, and ATC and highlights the importance of comprehensive, integrated strategies in the management of traumatic hemorrhage to prevent blood failure. A multidisciplinary approach is essential to address these interconnected factors effectively and to improve patient outcomes.

Missingness matters: a secondary analysis of thromboelastography measurements from a recent prehospital randomized tranexamic acid clinical trial

Background

Tranexamic acid (TXA) has been hypothesized to mitigate coagulopathy in patients after traumatic injury. Despite previous prehospital clinical trials demonstrating a TXA survival benefit, none have demonstrated correlated changes in thromboelastography (TEG) parameters. We sought to analyze if missing TEG data contributed to this paucity of findings.

Methods

We performed a secondary analysis of the Study of Tranexamic Acid During Air Medical and Ground Prehospital Transport Trial. We compared patients that received TEG (YES-TEG) and patients unable to be sampled (NO-TEG) to analyze subgroups in which to investigate TEG differences. TEG parameter differences across TXA intervention arms were assessed within subgroups disproportionately present in the NO-TEG relative to the YES-TEG cohort. Generalized linear models controlling for potential confounders were applied to findings with p<0.10 on univariate analysis.

Results

NO-TEG patients had lower prehospital systolic blood pressure (SBP) (100 (78, 140) vs 125 (88, 147), p<0.01), lower prehospital Glascow Coma Score (14 (3, 15) vs 15 (12, 15), p<0.01), greater rates of prehospital intubation (39.4% vs 24.4%, p<0.01) and greater mortality at 30 days (36.4% vs 6.8%, p<0.01). NO-TEG patients had a greater international normalized ratio relative to the YES-TEG subgroup (1.2 (1.1, 1.5) vs 1.1 (1.0, 1.2), p=0.04). Within a severe prehospital shock cohort (SBP<70), TXA was associated with a significant decrease in clot lysis at 30 min on multivariate analysis (β=-27.6, 95% CI (-51.3 to -3.9), p=0.02).

Conclusions

Missing data, due to the logistical challenges of sampling certain severely injured patients, may be associated with a lack of TEG parameter changes on TXA administration in the primary analysis. Previous demonstration of TXA's survival benefit in patients with severe prehospital shock in tandem with the current findings supports the notion that TXA acts at least partially by improving clot integrity.

Level of evidence

Level II.

Mechanism matters: mortality and endothelial cell damage marker differences between blunt and penetrating traumatic injuries across three prehospital clinical trials

Injury mechanism is an important consideration when conducting clinical trials in trauma. Mechanisms of injury may be associated with differences in mortality risk and immune response to injury, impacting the potential success of the trial. We sought to characterize clinical and endothelial cell damage marker differences across blunt and penetrating injured patients enrolled in three large, prehospital randomized trials which focused on hemorrhagic shock. In this secondary analysis, patients with systolic blood pressure < 70 or systolic blood pressure < 90 and heart rate > 108 were included. In addition, patients with both blunt and penetrating injuries were excluded. The primary outcome was 30-day mortality. Mortality was characterized using Kaplan-Meier and Cox proportional-hazards models. Generalized linear models were used to compare biomarkers. Chi squared tests and Wilcoxon rank-sum were used to compare secondary outcomes. We characterized data of 696 enrolled patients that met all secondary analysis inclusion criteria. Blunt injured patients had significantly greater 24-h (18.6% vs. 10.7%, log rank p = 0.048) and 30-day mortality rates (29.7% vs. 14.0%, log rank p = 0.001) relative to penetrating injured patients with a different time course. After adjusting for confounders, blunt mechanism of injury was independently predictive of mortality at 30-days (HR 1.84, 95% CI 1.06-3.20, p = 0.029), but not 24-h (HR 1.65, 95% CI 0.86-3.18, p = 0.133). Elevated admission levels of endothelial cell damage markers, VEGF, syndecan-1, TM, S100A10, suPAR and HcDNA were associated with blunt mechanism of injury. Although there was no difference in multiple organ failure (MOF) rates across injury mechanism (48.4% vs. 42.98%, p = 0.275), blunt injured patients had higher Denver MOF score (p < 0.01). The significant increase in 30-day mortality and endothelial cell damage markers in blunt injury relative to penetrating injured patients highlights the importance of considering mechanism of injury within the inclusion and exclusion criteria of future clinical trials.

Damage control surgery: old concepts and new indications

PURPOSE OF REVIEW

While the principles of damage control surgery - rapid hemorrhage and contamination control with correction of physiologic derangements followed by delayed definitive reconstruction - have remained consistent, forms of damage control intervention have evolved and proliferated dramatically. This review aims to provide a historic perspective of the early trends of damage control surgery as well as an updated understanding of its current state and future trends.

RECENT FINDINGS

Physiologically depleted patients in shock due to both traumatic and nontraumatic causes are often treated with damage control laparotomy and surgical principles. Damage control surgery has also been shown to be safe and effective in thoracic and orthopedic injuries. Damage control resuscitation is used in conjunction with surgical source control to restore patient physiology and prevent further collapse. The overuse of damage control laparotomy, however, is associated with increased morbidity and complications. With advancing technology, catheter- and stent-based endovascular modalities are playing a larger role in the resuscitation and definitive care of patients.

SUMMARY

Optimal outcome in the care of the most severely injured patients requires judicious use of damage control surgery supplemented by advancements in resuscitation and surgical adjuncts.

Damage Control Surgery and Transfer in Emergency General Surgery

Selective non traumatic emergency surgery patients are targets for damage control surgery (DCS) to prevent or treat abdominal compartment syndrome and the lethal triad. However, DCS is still a subject of controversy. As a concept, DCS describes a series of abbreviated surgical procedures to allow rapid source control of hemorrhage and contamination in patients with circulatory shock to allow resuscitation and stabilization in the intensive care unit followed by delayed return to the operating room for definitive surgical management once the patient becomes physiologic stable. If appropriately applied, the DCS morbidity and mortality can be significantly reduced.

Could machine learning algorithms help us predict massive bleeding at prehospital level?

OBJECTIVE

Comparison of the predictive ability of various machine learning algorithms (MLA) versus traditional prediction scales (TPS) for massive hemorrhage (MH) in patients with severe traumatic injury (STI).

DESIGN

On a database of a retrospective cohort with prehospital clinical variables and MH outcome, a treatment of the database was performed to be able to apply the different AML, obtaining a total set of 473 patients (80% training, 20% validation). For modeling, proportional imputation and cross validation were performed. The predictive power was evaluated with the ROC metric and the importance of the variables using the Shapley values.

SETTING

Out-of-hospital care of patients with STI.

PARTICIPANTS

Patients with STI treated out-of-hospital by a out-of-hospital medical service from January 2010 to December 2015 and transferred to a trauma center in Madrid.

INTERVENTIONS

None.

MAIN VARIABLES OF INTEREST

Obtaining and comparing the "Receiver Operating Characteristic curve" (ROC curve) metric of four MLAs: "random forest" (RF), "vector support machine" (SVM), "gradient boosting machine" (GBM) and "neural network" (NN) with the results obtained with TPS.

RESULTS

The different AML reached ROC values higher than 0.85, having medians close to 0.98. We found no significant differences between AMLs. Each AML offers a different set of more important variables with a predominance of hemodynamic, resuscitation variables and neurological impairment.

CONCLUSIONS

MLA may be helpful in patients with HM by outperforming TPS.

Achieving balanced transfusion early in critically bleeding trauma patients: an observational study exploring the effect of attending trauma surgical presence during resuscitation

Background

After 15 years of damage control resuscitation (DCR), studies still report high mortality rates for critically bleeding trauma patients. Adherence to massive hemorrhage protocols (MHPs) based on a 1:1:1 ratio of plasma, platelets, and red blood cells (RBCs) as part of DCR has been shown to improve outcomes. We wanted to assess MHP use in the early (6 hours from admission), critical phase of DCR and its impact on mortality. We hypothesized that the presence of an attending trauma surgeon during all MHP activations from 2013 would contribute to improving institutional resuscitation strategies and patient outcomes.

Methods

We conducted a retrospective analysis of all trauma patients receiving ≥10 RBCs within 6 hours of admission and included in the institutional trauma registry between 2009 and 2019. The cohort was divided in period 1 (P1): January 2009-August 2013, and period 2 (P2): September 2013-December 2019 for comparison of outcomes.

Results

A total of 141 patients were included, 81 in P1 and 60 in P2. Baseline characteristics were similar between the groups for Injury Severity Score, lactate, Glasgow Coma Scale, and base deficit. Patients in P2 received more plasma (16 units vs. 12 units; p<0.01), resulting in a more balanced plasma:RBC ratio (1.00 vs. 0.74; p<0.01), and platelets:RBC ratio (1.11 vs. 0.92; p<0.01). All-cause mortality rates decreased from P1 to P2, at 6 hours (22% to 8%; p=0.03), at 24 hours (36% vs 13%; p<0.01), and at 30 days (48% vs 30%, p=0.03), respectively. A stepwise logistic regression model predicted an OR of 0.27 (95% CI 0.08 to 0.93) for dying when admitted in P2.

Conclusions

Achieving balanced transfusion rates at 6 hours, facilitated by the presence of an attending trauma surgeon at all MHP activations, coincided with a reduction in all-cause mortality and hemorrhage-related deaths in massively transfused trauma patients at 6 hours, 24 hours, and 30 days.

Level of evidence

IV.

Outcome of severely injured patients in a unique trauma system with 24/7 double trauma surgeon on-call service

BACKGROUND

The presence of in-house attending trauma surgeons has improved efficiency of processes in the treatment of polytrauma patients. However, literature remains equivocal regarding the influence of the presence of in-house attendings on mortality. In our hospital there is a double trauma surgeon on-call system. In this system an in-house trauma surgeon is 24/7 backed up by a second trauma surgeon to assist with urgent surgery or multiple casualties. The aim of this study was to evaluate outcome in severely injured patients in this unique trauma system.

METHODS

From 2014 to 2021, a prospective population-based cohort consisting of consecutive polytrauma patients aged ≥ 15 years requiring both urgent surgery (≤ 24h) and admission to Intensive Care Unit (ICU) was investigated. Demographics, treatment, outcome parameters and pre- and in-hospital transfer times were analyzed.

RESULTS

Three hundred thirteen patients with a median age of 44 years (71% male), and median Injury Severity Score (ISS) of 33 were included. Mortality rate was 19% (68% due to traumatic brain injury). All patients stayed ≤ 32 min in ED before transport to either CT or OR. Fifty-one percent of patients who needed damage control surgery (DCS) had a more deranged physiology, needed more blood products, were more quickly in OR with shorter time in OR, than patients with early definitive care (EDC). There was no difference in mortality rate between DCS and EDC patients. Fifty-six percent of patients had surgery during off-hours. There was no difference in outcome between patients who had surgery during daytime and during off-hours. Death could possibly have been prevented in 1 exsanguinating patient (1.7%).

CONCLUSION

In this cohort of severely injured patients in need of urgent surgery and ICU support it was demonstrated that surgical decision making was swift and accurate with low preventable death rates. 24/7 Physical presence of a dedicated trauma team has likely contributed to these good outcomes.

Neutrophil-to-lymphocyte ratio in relation to trauma severity as prognosis factors in patients with multiple injuries complicated by multiple organ dysfunction syndrome: A retrospective analysis

OBJECTIVE

This study aimed to explore potential risk factors for the occurrence of multiple organ dysfunction syndrome (MODS) in patients with multiple injuries by evaluating neutrophil-to-lymphocyte ratio (NLR)-associated trauma severity.

METHODS

This retrospective case-control study included 95 patients with multiple injuries, who were admitted to our hospital (between January 2018 and December 2020). Clinical data including gender, age, underlying disease, number of injury sites (NIS), injury severity score (ISS), hemoglobin level within 24 h of admission (HL-24h), neutrophil count (NC), white blood cell count, platelet count (PC), NLR, d-dimer level, activated partial thromboplastin time (APTT), complicated shock within 24 h of admission (CS-24h), length of stay, as well as prognostic outcome was systematically analyzed. According to MODS occurrence, patients were divided into a MODS group (n = 27) and a non-MODS group (n = 68). The risk factors affecting patients with multiple injuries complicated by MODS were identified using univariate and multivariate logistic regression analyses. Candidate risk factors were further analyzed using receiver operating characteristic (ROC) curves.

RESULTS

Univariate analysis revealed a significant difference between the MODS and non-MODA groups in terms of NIS, ISS, HL-24h, PC, APTT, d-dimer level, CS-24h, NLR, NC, prognostic outcome, and other indicators (p < .05). Multivariate logistic regression analysis showed that  d-dimer levels within 24 h of admission and ISS, NLR, and CS-24h were significantly associated with multiple injuries complicated by MODS. Compared with the non-MODS controls, the NLR in the MODS group showed a much higher level and tended to rise with the increase in ISS score, indicating a significant intergroup difference (p < .05). The ROC curve analysis results suggested that the NLR had good sensitivity and specificity for predicting the prognosis of patients with MODS with multiple injuries.

CONCLUSION

d-dimer level, ISS, NLR, and CS-24h are important risk factors for MODS in patients with multiple injuries. Notably, NLR expression may be a good indicator of injury severity and predictor of the occurrence of MODS in patients with multiple injuries. Therefore, assessment of injury severity and coagulation function, active resuscitation, as well as prevention of infection should be emphasized during treatment of multiple injuries, to reduce and prevent the risk of MODS in patients with multiple injuries.

Air Medical Blood Transfusion as a Trigger of Massive Transfusion Protocol

Air medical services can improve access to blood products at the point of injury. Studies have shown that early activation of mass transfusion protocols (MTPs) can improve the survival of trauma patients by up to 25%. There are several scoring systems to guide early activation, but the use of a single criterion has been elusive. Our study sought to determine if air medical administration of blood products was a risk factor for massive transfusion activation and utilization of prehospital vital signs for calculation of the shock index. In our retrospective study, we evaluated adult trauma patients transfused by helicopter emergency medical services (HEMS) and as a control all patients in our institution receiving the MTP. Our study found HEMS blood transfusion was not a reliable trigger for MTP, although the sample size may have limited our findings. We found that HEMS care resulted in an overall reduction in the volume of transfusion and an improvement in hemodynamic parameters upon trauma center arrival. HEMS transfusion and a higher rate of tranexamic acid administration may have contributed to these findings. Of note, the assessment of blood consumption score and shock index were nonspecific in the study populations.

Blood component resuscitative strategies to mitigate endotheliopathy in a murine hemorrhagic shock model

BACKGROUND

Resuscitation with plasma components has been shown to improve endotheliopathy induced by hemorrhagic shock, but the optimal resuscitation strategy to preserve the endothelial glycocalyx has yet to be defined. The aim of this study was to determine if resuscitation with lactated Ringer's (LR), whole blood (WB), packed red blood cells (RBCs), platelet-rich plasma (PRP), platelet poor plasma, balanced RBC:PRP (1:1), or day 14 (d14) RBC would best minimize endothelial damage following shock.

METHODS

Male C57BL/6 mice were hemorrhaged to a goal mean arterial pressure of 25 mm Hg for 1 hour. Unshocked sham mice served as controls. Mice were then resuscitated with equal volumes of LR, WB, RBC, PRP, platelet poor plasma, 1:1, or d14 RBC and then sacrificed at 1, 4, or 24 hours (n = 5). Serum was analyzed for syndecan-1, ubiquitin C-terminal hydrolase L1, and cytokine concentrations. Lungs underwent syndecan-1 immunostaining, and lung injury scores were calculated after hematoxylin and eosin. Proteolytic cleavage of the endothelial glycocalyx was assessed by serum matrix metalloprotease 9 levels.

RESULTS

Serum syndecan-1 and ubiquitin C-terminal hydrolase L1 levels were significantly increased following resuscitation with d14 RBC compared with other groups. Early elevation in lung syndecan-1 staining was noted in LR-treated mice, while d14 mice showed decreased staining compared with sham mice following shock. Lung injury scores were significantly elevated 4 hours after resuscitation with LR and d14 RBC compared with WB. Serum matrix metalloprotease 9 levels were significantly increased at 1 and 4 hours in d14 mice compared with sham mice. Systemic inflammation was increased in animals receiving LR, 1:1, or d14 RBC.

CONCLUSION

Resuscitation with WB following hemorrhagic shock reduces endothelial syndecan-1 shedding and mitigates lung injury. Aged RBC and LR fail to attenuate endothelial injury following hemorrhagic shock. Further research will be necessary to determine the effect of each of these resuscitative fluids in a hemorrhagic shock model with the addition of tissue injury.

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

Importance

It is not clear which severely injured patients with hemorrhagic shock may benefit most from a 1:1:1 vs 1:1:2 (plasma:platelets:red blood cells) resuscitation strategy. Identification of trauma molecular endotypes may reveal subgroups of patients with differential treatment response to various resuscitation strategies.

Objective

To derive trauma endotypes (TEs) from molecular data and determine whether these endotypes are associated with mortality and differential treatment response to 1:1:1 vs 1:1:2 resuscitation strategies.

Design, Setting, and Participants

This was a secondary analysis of the Pragmatic, Randomized Optimal Platelet and Plasma Ratios (PROPPR) randomized clinical trial. The study cohort included individuals with severe injury from 12 North American trauma centers. The cohort was taken from the participants in the PROPPR trial who had complete plasma biomarker data available. Study data were analyzed on August 2, 2021, to October 25, 2022.

Exposures

TEs identified by K-means clustering of plasma biomarkers collected at hospital arrival.

Main Outcomes and Measures

An association between TEs and 30-day mortality was tested using multivariable relative risk (RR) regression adjusting for age, sex, trauma center, mechanism of injury, and injury severity score (ISS). Differential treatment response to transfusion strategy was assessed using an RR regression model for 30-day mortality by incorporating an interaction term for the product of endotype and treatment group adjusting for age, sex, trauma center, mechanism of injury, and ISS.

Results

A total of 478 participants (median [IQR] age, 34.5 [25-51] years; 384 male [80%]) of the 680 participants in the PROPPR trial were included in this study analysis. A 2-class model that had optimal performance in K-means clustering was found. TE-1 (n = 270) was characterized by higher plasma concentrations of inflammatory biomarkers (eg, interleukin 8 and tumor necrosis factor α) and significantly higher 30-day mortality compared with TE-2 (n = 208). There was a significant interaction between treatment arm and TE for 30-day mortality. Mortality in TE-1 was 28.6% with 1:1:2 treatment vs 32.6% with 1:1:1 treatment, whereas mortality in TE-2 was 24.5% with 1:1:2 treatment vs 7.3% with 1:1:1 treatment (P for interaction = .001).

Conclusions and Relevance

Results of this secondary analysis suggest that endotypes derived from plasma biomarkers in trauma patients at hospital arrival were associated with a differential response to 1:1:1 vs 1:1:2 resuscitation strategies in trauma patients with severe injury. These findings support the concept of molecular heterogeneity in critically ill trauma populations and have implications for tailoring therapy for patients at high risk for adverse outcomes.

Balanced resuscitation: application to the paediatric trauma population

PURPOSE OF REVIEW

Trauma is the leading cause of death in children over 5 years old. Early mortality is associated with trauma-induced coagulopathy (TIC), with balanced resuscitation potentially mitigating the effects of TIC. We review TIC, balanced resuscitation and the best evidence for crystalloid fluid versus early blood products, massive transfusion protocol (MTP) and the optimal ratio for blood products.

RECENT FINDINGS

Crystalloid fluids have been associated with adverse events in paediatric trauma patients. However, the best way to implement early blood products remains unclear; MTP has only shown improved time to blood products without clear clinical improvement. The indications to start blood products are also currently under investigation with several scoring systems and clinical indications being studied. Current studies on the blood product ratio suggest a 1 : 1 ratio for plasma:pRBC is likely ideal, but prospective studies are needed to further support its use.

SUMMARY

Balanced resuscitation strategies of minimal crystalloid use and early administration of blood products are associated with improved morbidity in paediatric trauma patients but unclear mortality benefit. Current evidence suggests that the utilization of MTPs with 1 : 1 plasma:pRBC ratio may improve morbidity, but more research is needed.

Ultramassive Transfusion for Trauma in the Age of Hemostatic Resuscitation: A Retrospective Single-Center Cohort From a Large US Level-1 Trauma Center, 2011-2021

BACKGROUND

Uncontrolled bleeding is a leading cause of death in trauma. In the last 40 years, ultramassive transfusion (UMT; ≥20 units of red blood cells [RBCs]/24 hours) for trauma has been associated with 50% to 80% mortality; the question remains as to whether the increasing number of units transfused in urgent resuscitation is a marker of futility. We asked whether the frequency and outcomes of UMT have changed in the era of hemostatic resuscitation.

METHODS

We performed a retrospective cohort study of all UMTs in the first 24 hours of care over an 11-year period at a major US level-1 adult and pediatric trauma center. UMT patients were identified, and a dataset was built by linking blood bank and trauma registry data, then reviewing individual electronic health records. Success in achieving hemostatic proportions of blood products was estimated as (units of plasma + apheresis-platelets-in-plasma + cryoprecipitate-pools + whole blood]/[all units given] ≥0.5. Demographics, injury type (blunt or penetrating), severity (Injury Severity Score [ISS]), severity pattern (Abbreviated Injury Scale score for head [AIS-Head] ≥4), admitting laboratory, transfusion, selected emergency department interventions, and discharge status were assessed using χ2 tests of categorical association, the Student t-test of means, and multivariable logistic regression. P <.05 was considered significant.

RESULTS

Among 66,734 trauma admissions from April 6, 2011 to December 31, 2021, we identified 6288 (9.4%) who received any blood products in the first 24 hours, 159 of whom received UMT (0.23%; 154 aged 18-90 + 5 aged 9-17), 81% in hemostatic proportions. Overall mortality was 65% (n = 103); mean ISS = 40; median time to death, 6.1 hours. In univariate analyses, death was not associated with age, sex, or more RBC units transfused beyond 20 but was associated with blunt injury, increasing injury severity, severe head injury, and failure to receive hemostatic blood product ratios. Mortality was also associated with decreased pH and evidence of coagulopathy at admission, especially hypofibrinogenemia. Multivariable logistic regression showed severe head injury, admission hypofibrinogenemia and not receiving a hemostatic resuscitation proportion of blood products as independently associated with death.

CONCLUSIONS

One in 420 acute trauma patients at our center received UMT, a historically low rate. A third of these patients lived, and UMT was not itself a marker of futility. Early identification of coagulopathy was possible, and failure to give blood components in hemostatic ratios was associated with excess mortality.

Higher center volume is significantly associated with lower mortality in trauma patients with shock

INTRODUCTION

Injured patients presenting in shock are at high risk of mortality despite numerous efforts to improve resuscitation. Identifying differences in outcomes among centers for this population could yield insights to improve performance. We hypothesized that trauma centers treating higher volumes of patients in shock would have lower risk-adjusted mortality.

METHODS

We queried the Pennsylvania Trauma Outcomes Study from 2016 to 2018 for injured patients ≥16 years of age at Level I&II trauma centers who had an initial systolic blood pressure (SBP) of <90 mmHg. We excluded patients with critical head injury (abbreviated injury score [AIS] head ≥5) and patients coming from centers with a shock patient volume of ≤10 for the study period. The primary exposure was tertile of center-level shock patient volume (low, medium, or high volume). We compared risk-adjusted mortality by tertile of volume using multivariable Cox proportional hazards model incorporating age, injury severity, mechanism, and physiology.

RESULTS

Of 1,805 included patients at 29 centers, 915 (50.7%) died. The median annual shock trauma patient volume was 9 patients for low volume centers, medium 19.5, and high 37. Median ISS was higher at high volume compared to low volume centers (22 vs 18, p <0.001). Raw mortality was 54.9% at high volume centers, 46.7% for medium, and 42.9% for low. Time elapsed from arrival to emergency department (ED) to the operating room (OR) was lower at high volume than low volume centers (median 47 vs 78 min) p = 0.003. In adjusted analysis, hazard ratio for high volume centers (referenced to low volume) was 0.76 (95% CI 0.59-0.97, p = 0.030).

CONCLUSION

After adjusting for patient physiology and injury characteristics, center-level volume is significantly associated with mortality. Future studies should seek to identify key practices associated with improved outcomes in high-volume centers. Furthermore, shock patient volume should be considered when new trauma centers are opened.

Achieving optimal massive transfusion ratios: The trauma white board, whole blood, and liquid plasma. Real world low-tech solutions for a high stakes issue

BACKGROUND

It is well established that achieving optimal ratios of packed red blood cells (PRBC) to fresh frozen plasma (FFP) to platelet ratios during massive transfusion leads to improved outcomes but is difficult to accomplish.

METHODS

Between September 2018 and May 2019 our level 2 trauma center implemented 3 new processes to optimize transfusion ratios during massive transfusion protocol (MTP). Two units of low titer group O whole blood (LTOWB) were added as the first step to our MTP. Second, a dry erase board whiteboard was attached to each fluid warmer for real time recording of transfusions. Last, liquid plasma was incorporated into our MTP. We performed a retrospective review evaluating PRBC:FFP ratios for patients who had the massive transfusion protocol initiated and received 4 or more units of blood.

RESULTS

A total of 50 patients had the massive transfusion protocol initiated and received 4 or more units of PRBCs and/or LTOWB within 4 h of arrival. There were 21 patients evaluated prior to protocol changes and 29 patients after the changes. In the study group mean age, sex, pulse, systolic blood pressure (SBP), and injury severity scale (ISS) on admission were not different. In the pre-protocol (preP) group 90% of patients were blunt trauma and in the post-protocol group (postP) 72% were blunt trauma, p = 0. 22. For the preP group the mean units of PRBCs was 7.6 units and FFP 4.7 units. PostP the mean units of PRBCs was 11.4 units and FFP 10.0 units. PRBC/FFP ratios were 1.7 preP and 1.2 postP, p = 0.0072.

CONCLUSION

The institution of whole blood, use of the trauma white board, and the addition of liquid plasma to our transfusion services have allowed us to approach a 1:1 transfusion ratio during the course of our massive transfusions.

Trauma-related electrolyte disturbances: From resuscitation to rhabdomyolysis

Traumatic injury results in drastic changes to a patient's normal physiology. The hormonal stress response, as well as some treatment strategies, lead to significant disruptions in electrolyte homeostasis that are important for clinicians to understand. In addition, advances in fluid resuscitation and modern transfusion practices have led to their own unique set of consequences, which we are just beginning to appreciate. Special attention is placed on rhabdomyolysis, as this distinct entity represents an extreme example of injury induced electrolyte derangements. This review describes the physiologic response to trauma and highlights some of the important electrolyte abnormalities that can be encountered while caring for the injured patient.

Metabolic systems analysis identifies a novel mechanism contributing to shock in patients with endotheliopathy of trauma (EoT) involving thromboxane A2 and LTC4

Purpose

Endotheliopathy of trauma (EoT), as defined by circulating levels of syndecan-1 ≥ 40 ng/mL, has been reported to be associated with significantly increased transfusion requirements and a doubled 30-day mortality. Increased shedding of the glycocalyx points toward the endothelial cell membrane composition as important for the clinical outcome being the rationale for this study.

Results

The plasma metabolome of 95 severely injured trauma patients was investigated by mass spectrometry, and patients with EoT vs. non-EoT were compared by partial least square-discriminant analysis, identifying succinic acid as the top metabolite to differentiate EoT and non-EoT patients (VIP score = 3). EoT and non-EoT patients' metabolic flux profile was inferred by integrating the corresponding plasma metabolome data into a genome-scale metabolic network reconstruction analysis and performing a functional study of the metabolic capabilities of each group. Model predictions showed a decrease in cholesterol metabolism secondary to impaired mevalonate synthesis in EoT compared to non-EoT patients. Intracellular task analysis indicated decreased synthesis of thromboxanA2 and leukotrienes, as well as a lower carnitine palmitoyltransferase I activity in EoT compared to non-EoT patients. Sensitivity analysis also showed a significantly high dependence of eicosanoid-associated metabolic tasks on alpha-linolenic acid as unique to EoT patients.

Conclusions

Model-driven analysis of the endothelial cells' metabolism identified potential novel targets as impaired thromboxane A2 and leukotriene synthesis in EoT patients when compared to non-EoT patients. Reduced thromboxane A2 and leukotriene availability in the microvasculature impairs vasoconstriction ability and may thus contribute to shock in EoT patients. These findings are supported by extensive scientific literature; however, further investigations are required on these findings.

Challenges in abdominal re-exploration for war casualties following on-site abdominal trauma surgery and subsequent delayed arrival to definitive medical care abroad - an unusual scenario

Background

During the Syrian civil war, patients were initially treated on-site in Syria and later transferred to medical centers in Israel. Relevant details concerning the exact nature of injury and medical/surgical care received in Syria were unavailable to clinicians in Israel. Many of these patients required abdominal re-exploration for obvious or suspected problems related to their injury. Our aim is to present our approach to abdominal trauma patients who survived initial on-site surgery and needed subsequent abdominal re-exploration abroad, in our medical center.

Methods

Clinical data from all medical records were retrospectively analyzed. Each patient underwent total body computerized tomography on arrival, revealing diverse multi-organ trauma. We divided the patient population who had abdominal trauma into 4 sub-groups according to the location in which abdominal surgical intervention was performed (abdominal surgery performed only in Syria, surgery in Syria and subsequent re-laparotomy in Israel, abdominal surgery only in Israel, and management of patients without abdominal surgical intervention). We focused on missed injuries and post-operative complications in the re-laparotomy sub-group.

Results

By July 2018, 1331 trauma patients had been admitted to our hospital, of whom 236 had suffered abdominal trauma. Life-saving abdominal intervention was performed in 138 patients in Syria before arrival to our medical center.

A total of 79 patients underwent abdominal surgery in Israel, of whom 46 (33%) required re-laparotomy. The absence of any communication between the surgical teams across the border markedly affected our medical approach. Indications for re-exploration included severe peritoneal inflammation, neglected or overlooked abdominal foreign bodies, hemodynamic instability and intestinal fistula. Mortality occurred in 37/236 patients, with severe abdominal trauma as the main cause of fatality in 10 of them (4.2%), usually following urgent re-laparotomy.

Conclusions

Lack of information about the circumstances of injury in an environment of catastrophe in Syria at the time and the absence of professional communication between the surgical teams across the border markedly dictated our medical approach. Our concerns were that some patients looked deceptively stable while others had potentially hidden injuries. We had no information on who had had definitive versus damage control surgery in Syria. The fact that re-operation was not performed by the same team responsible for initial abdominal intervention also posed major diagnostic challenges and warranted increased clinical suspicion and a change in our standard medical approach.

[Early changes within the lymphocyte population are associated with the long term prognosis in severely injured patients]

OBJECTIVE

To investigate the relationship between early lymphocyte responses and the prognosis in severely injured patients.

METHODS

Consecutive patients with severe trauma who were treated in Peking University People's Hospital Trauma Medical Center between June 2017 and June 2020 were enrolled in this restropective chart-review study. According to the responses of lymphocyte after severe injury, the patients were divided into three groups, group 1: lymphopenia-returned to normal; group 2: persistent lymphopenia; group 3: never lymphopenic, and the outcome of 28 d were recorded. Clinical data such as gender, age, base excess, mechanism of injury, Glasgow coma scale (GCS), injury severity score (ISS) and massive blood transfusion were collected. Perform statistical analysis on the collected clinical data to understand the trend of lymphocyte changes in early trauma and the relationship with prognosis. In order to eliminate the interference of age, stratification was carried out according to whether the age was ≥ 65 years old, in different age groups, they were grouped according to whether the length of stay was ≥ 28 d, and the relationship between lymphocyte trend and length of stay was discussed.

RESULTS

A total of 83 patients were included, 66 males and 17 females. The main injury mechanisms were traffic accident injuries and high-altitude fall injuries. The average ISS was (30±11) points. 65 patients had lymphopenia on the day of injury, 32 of them returned to normal on the 5th day, and the rest did not recover; the other 18 patients had normal lymphocyte levels after injury. Patients which are failure to normalize lymphopenia within the first 5 days following admission was related with the long hospitalization time and higher 28 d mortality rate. After further stratification by age, failure to normalize lymphopenia within the first 5 days following admission in the elderly group (age ≥65 years) was a risk factor for prolonged hospital stay (≥28 d), P=0.04. While in younger group, a high level of neutrophils within the first 5 d following admission was a risk factor for bad outcome.

CONCLUSION

A failure to normalize lymphopenia in severely injured patients is associated with significantly higher mortality and longer hospital stay. This study reveals lymphocytes can be used as a reliable indicator for the prognostic evaluation.

Green Plasma has a Superior Hemostatic Profile Compared With Standard Color Plasma

BACKGROUND

Limitations in available donors have dramatically reduced plasma availability over the past several decades, concurrent with increasing demand for some types of plasma. Plasma from female donors who are pregnant or taking oral contraceptives often has a green appearance, which frequently results in these units being discarded. This pilot study aimed to evaluate the hemostatic potential of green compared to standard-color plasma.

MATERIALS AND METHODS

Plasma from twelve blood group-matched female and twelve male donors was obtained from the local blood center. Six of the female and all of the male units of plasma had a normal appearance (STANDARD), while six of the female units were grossly green (GREEN). The hemostatic potential was evaluated by thrombelastography (TEG), calibrated automated thrombogram (CAT), and coagulation factor level measurements. Univariate analysis was performed using Wilcoxon Rank-Sum.

RESULTS

GREEN plasma was more procoagulant for all TEG values (r-value, k-time, angle, mA) when compared to STANDARD plasma. Differences were also observed in coagulation factor levels, with GREEN plasma having higher than STANDARD (factors II; VII, IX; X, XI, Protein S, and plasminogen); conversely, GREEN plasma had a longer lag time in CAT.

DISCUSSION

This pilot study demonstrates that female donors with green plasma have a superior hemostatic profile than standard plasma. GREEN plasma should be further investigated for its safety profile and hemostatic potential, so if it is found to be a safe and functionally non-inferior product, it should be actively re-introduced for transfusion in bleeding patients.

Mesenchymal stem cell extracellular vesicles mitigate vascular permeability and injury in the small intestine and lung in a mouse model of hemorrhagic shock and trauma

BACKGROUND

Hemorrhagic shock and trauma (HS/T)-induced gut injury may play a critical role in the development of multi-organ failure. Novel therapies that target gut injury and vascular permeability early after HS/T could have substantial impacts on trauma patients. In this study, we investigate the therapeutic potential of human mesenchymal stem cells (MSCs) and MSC-derived extracellular vesicles (MSC EVs) in vivo in HS/T in mice and in vitro in Caco-2 human intestinal epithelial cells.

METHODS

In vivo, using a mouse model of HS/T, vascular permeability to a 10-kDa dextran dye and histopathologic injury in the small intestine and lungs were measured among mice. Groups were (1) sham, (2) HS/T + lactated Ringer's (LR), (3) HS/T + MSCs, and (4) HS/T + MSC EVs. In vitro, Caco-2 cell monolayer integrity was evaluated by an epithelial cell impedance assay. Caco-2 cells were pretreated with control media, MSC conditioned media (CM), or MSC EVs, then challenged with hydrogen peroxide (H2O2).

RESULTS

In vivo, both MSCs and MSC EVs significantly reduced vascular permeability in the small intestine (fluorescence units: sham, 456 ± 88; LR, 1067 ± 295; MSC, 765 ± 258; MSC EV, 715 ± 200) and lung (sham, 297 ± 155; LR, 791 ± 331; MSC, 331 ± 172; MSC EV, 303 ± 88). Histopathologic injury in the small intestine and lung was also attenuated by MSCs and MSC EVs. In vitro, MSC CM but not MSC EVs attenuated the increased permeability among Caco-2 cell monolayers challenged with H2O2.

CONCLUSION

Mesenchymal stem cell EVs recapitulate the effects of MSCs in reducing vascular permeability and injury in the small intestine and lungs in vivo, suggesting MSC EVs may be a potential cell-free therapy targeting multi-organ dysfunction in HS/T. This is the first study to demonstrate that MSC EVs improve both gut and lung injury in an animal model of HS/T.

Physiology dictated treatment after severe trauma: timing is everything

INTRODUCTION

Damage control strategies in resuscitation and (fracture) surgery have become standard of care in the treatment of severely injured patients. It is suggested that damage control improves survival and decreases the incidence of organ failure. However, these strategies can possibly increase the risk of complications such as infections. Indication for damage control procedures is guided by physiological parameters, type of injury, and the surgeon's experience. We analyzed outcomes of severely injured patients who underwent emergency surgery.

METHODS

Severely injured patients, admitted to a level-1 trauma center ICU from 2016 to 2020 who were in need of ventilator support and required immediate surgical intervention ( ≤24 h) were included. Demographics, treatment, and outcome parameters were analyzed.

RESULTS

Hundred ninety-five patients were identified with a median ISS of 33 (IQR 25-38). Ninety-seven patients underwent immediate definitive surgery (ETC group), while 98 patients were first treated according to damage control principles with abbreviated surgery (DCS group). Although ISS was similar in both groups, DCS patients were younger, suffered from more severe truncal injuries, were more frequently in shock with more severe acidosis and coagulopathy, and received more blood products. ETC patients with traumatic brain injury needed more often a craniotomy. Seventy-four percent of DCS patients received definitive surgery in the second surgical procedure. There was no difference in mortality, nor any other outcome including organ failure and infections.

CONCLUSIONS

When in severely injured patients treatment is dictated by physiology into either early definitive surgery or damage control with multiple shorter procedures stretched over several days combined with aggressive resuscitation with blood products, outcome is comparable in terms of complications.

Factors Associated With Increased Mortality in Severe Abdominopelvic Injury

BACKGROUND

Associated injuries are thought to increase mortality in patients with severe abdominopelvic trauma. This study aimed to identify clinical factors contributing to increased mortality in patients with severe abdominopelvic trauma, with the hypothesis that a greater number of concomitant injuries would result in increased mortality.

METHODS

This was a retrospective review of the Trauma Quality Improvement Program (TQIP) database of patients ≥ 18 years with severe abdominopelvic trauma defined as having an abdominal Abbreviated Injury Score (AIS) ≥ 3 with pelvic fractures and/or iliac vessel injury (2015-2017). Primary outcome was in-hospital mortality based on concomitant body region injuries. Secondary outcomes included mortality at 6 h, 6 to 24 h, and after 24 h based on concomitant injuries, procedures performed, and transfusion requirements.

RESULTS

A total of 185,257 patients were included in this study. Survivors had more severely injured body regions than non-survivors (4 vs. 3, P < 0.001). Among those who died within 6 h, 28.5% of patients required a thoracic procedure and 43% required laparotomy compared to 6.3% and 22.1% among those who died after 24 h (P < 0.001). Head AIS ≥ 3 was the only body region that significantly contributed to overall mortality (OR 1.26, P < 0.001) along with laparotomy (OR 3.02, P < 0.001), neurosurgical procedures (2.82, P < 0.001) and thoracic procedures (2.28, P < 0.001). Non-survivors who died in < 6 h and 6-24 h had greater pRBC requirements than those who died after 24 h (15.5 and 19.5 vs. 8 units, P < 0.001).

CONCLUSION

Increased number of body regions injured does not contribute to greater mortality. Uncontrolled noncompressible torso hemorrhage rather than the burden of concomitant injuries is the major contributor to the high mortality associated with severe abdominopelvic injury.

Personalized modulation of coagulation factors using a thrombin dynamics model to treat trauma-induced coagulopathy

Current trauma-induced coagulopathy resuscitation protocols use slow laboratory measurements, rules-of-thumb, and clinician gestalt to administer large volumes of uncharacterized, non-tailored blood products. These one-size-fits-all treatment approaches have high mortality. Here, we provide significant evidence that trauma patient survival 24 h after hospital admission occurs if and only if blood protein coagulation factor concentrations equilibrate at a normal value, either from inadvertent plasma-based modulation or from innate compensation. This result motivates quantitatively guiding trauma patient coagulation factor levels while accounting for protein interactions. Toward such treatment, we develop a Goal-oriented Coagulation Management (GCM) algorithm, a personalized and automated ordered sequence of operations to compute and specify coagulation factor concentrations that rectify clotting. This novel GCM algorithm also integrates new control-oriented advancements that we make in this work: an improvement of a prior thrombin dynamics model that captures the coagulation process to control, a use of rapidly-measurable concentrations to help predict patient state, and an accounting of patient-specific effects and limitations when adding coagulation factors to remedy coagulopathy. Validation of the GCM algorithm's guidance shows superior performance over clinical practice in attaining normal coagulation factor concentrations and normal clotting profiles simultaneously.

Staying on target: Maintaining a balanced resuscitation during damage-control resuscitation improves survival

BACKGROUND

Damage-control resuscitation (DCR) improves survival in severely bleeding patients. However, deviating from balanced transfusion ratios during a resuscitation may limit this benefit. We hypothesized that maintaining a balanced resuscitation during DCR is independently associated with improved survival.

METHODS

This was a secondary analysis of the Prospective Observational Multicenter Major Trauma Transfusion (PROMMTT) study. Patients receiving >3 U of packed red blood cells (PRBCs) during any 1-hour period over the first 6 hours and surviving beyond 30 minutes were included. Linear regression assessed the effect of percent time in a high-ratio range on 24-hour survival. We identified an optimal ratio and percent of time above the target ratio threshold by Youden's index. We compared patients with a 6-hour ratio above the target and above the percent time threshold (on-target) with all others (off-target). Kaplan-Meier analysis assessed the combined effect of blood product ratio and percent time over the target ratio on 24-hour and 30-day survival. Multivariable logistic regression identified factors independently associated with 24-hour and 30-day survival.

RESULTS

Of 1,245 PROMMTT patients, 524 met the inclusion criteria. Optimal targets were plasma/PRBC and platelet/PRBC of 0.75 (3:4) and ≥40% time spent over this threshold. For plasma/PRBC, on-target (n = 213) versus off-target (n = 311) patients were younger (median, 31 years; interquartile range, [22-50] vs. 40 [25-54]; p = 0.002) with similar injury burdens and presenting physiology. Similar patterns were observed for platelet/PRBC on-target (n = 116) and off-target (n = 408) patients. After adjusting for differences, on-target plasma/PRBC patients had significantly improved 24-hour (odds ratio, 2.25; 95% confidence interval, 1.20-4.23) and 30-day (odds ratio, 1.97; 95% confidence interval, 1.14-3.41) survival, while on-target platelet/PRBC patients did not.

CONCLUSION

Maintaining a high ratio of plasma/PRBC during DCR is independently associated with improved survival. Performance improvement efforts and prospective studies should capture time spent in a high-ratio range.

LEVEL OF EVIDENCE

Epidemiologic/prognostic study, level II; Therapeutic, level IV.

Platelet to erythrocyte transfusion ratio and mortality in massively transfused trauma patients. A systematic review and meta-analysis

BACKGROUND

Platelet transfusion during major hemorrhage is important and often embedded in massive transfusion protocols. However, the optimal ratio of platelets to erythrocytes (platelet-rich plasma [PLT]/red blood cell [RBC] ratio) remains unclear. We hypothesized that high PLT/RBC ratios, as compared with low PLT/RBC ratios, are associated with improved survival in patients requiring massive transfusion.

METHODS

Four databases (Pubmed, CINAHL, EMBASE, and Cochrane) were systematically screened for literatures published until January 21, 2021, to determine the effect of PLT/RBC ratio on the primary outcome measure mortality at 1 hour to 6 hours and 24 hours and at 28 days to 30 days. Studies comparing various PLT/RBC ratios were included in the meta-analysis. Secondary outcomes included intensive care unit length of stay and in-hospital length of stay and total blood component use. The study protocol was registered in PROSPERO under number CRD42020165648.

RESULTS

The search identified a total of 8903 records. After removing the duplicates and second screening of title, abstract, and full text, a total of 59 articles were included in the analysis. Of these articles, 12 were included in the meta-analysis. Mortality at 1 hour to 6 hours, 24 hours, and 28 days to 30 days was significantly lower for high PLT/RBC ratios as compared with low PLT/RBC ratios.

CONCLUSION

Higher PLT/RBC ratios are associated with significantly lower 1-hour to 6-hour, 24-hour, 28-day to 30-day mortalities as compared with lower PLT/RBC ratios. The optimal PLT/RBC ratio for massive transfusion in trauma patients is approximately 1:1.

LEVEL OF EVIDENCE

Systematic review and meta-analysis, therapeutic Level III.

Trauma Prehospital Hypothermia Prevention and Treatment: An Observational Study

BACKGROUND

Hypothermia in trauma patients causes increased morbidity and mortality. Swift recognition and treatment are important to prevent any further heat loss. In addition, patient discomfort from cold decreases satisfaction with care. The administration of active and passive rewarming measures is important in the prevention and treatment of hypothermia, but their use in prehospital trauma patients in Portugal has not been previously reported.

OBJECTIVE

To assess the prevalence of hypothermia, the impact of rewarming measures, and the management of the discomfort caused by cold.

METHODS

This is a prospective cohort study conducted in Immediate Life Support Ambulances in Portugal between March 1, 2019, and April 30, 2020.

RESULTS

This study included records of 586 trauma patients; of whom, 66.2% were men. Cranioencephalic trauma was the most common trauma observed, followed by lower limb and thoracic traumas. Mean body temperature increased 0.12 °C between the first and last assessments (p < .05). Most patients experiencing a level of discomfort of 5 or more on a 0-10 scale reported improvement (from 17.2% to 2.4% after nurses' intervention). Warmed intravenous fluids proved to be effective (p < .05) in increasing body temperature, and passive rewarming measures were effective in preventing hypothermia.

CONCLUSIONS

Hypothermia management has to consider the initial temperature, the season, the available rewarming measures, and the objectives to be achieved. The optimization of resources for the monitoring and treatment of hypothermia should be a priority in prehospital assistance. The implementation of rewarming measures improves patients' outcomes and decreases the discomfort caused by cold in prehospital care.

Risk factors for abdominal surgical site infection after exploratory laparotomy among combat casualties

BACKGROUND

Surgical site infections (SSIs) are well-recognized complications after exploratory laparotomy for abdominal trauma; however, little is known about SSI development after exploration for battlefield abdominal trauma. We examined SSI risk factors after exploratory laparotomy among combat casualties.

METHODS

Military personnel with combat injuries sustained in Iraq and Afghanistan (June 2009 to May 2014) who underwent laparotomy and were evacuated to participating US military hospitals were included. Log-binominal regression was used to identify SSI risk factors.

RESULTS

Of 4,304 combat casualties, 341 patients underwent a total of 1,053 laparotomies. Abdominal SSIs were diagnosed in 49 patients (14.4%): 8% with organ space SSI, 4% with deep incisional SSI, and 4% with superficial SSIs (4 patients had multiple SSIs). Patients with SSIs had more colorectal (p < 0.001), small bowel (p = 0.010), duodenum (p = 0.006), pancreas (p = 0.032), and abdominal vascular injuries (p = 0.040), as well as prolonged open abdomen (p = 0.004) and more infections diagnosed before the SSI (or final exploratory laparotomy) versus non-SSI patients (p < 0.001). Sustaining colorectal injuries (risk ratio [RR], 3.20; 95% confidence interval [CI], 1.58-6.45), duodenum injuries (RR, 6.71; 95% CI, 1.73-25.58), and being diagnosed with prior infections (RR, 10.34; 95% CI, 5.05-21.10) were independently associated with any SSI development. For either organ space or deep incisional SSIs, non-intra-abdominal infections, fecal diversion, and duodenum injuries were independently associated, while being injured via an improvised explosive device was associated with reduced likelihood compared with penetrating nonblast (e.g., gunshot wounds) injuries. Non-intra-abdominal infections and hypotension were independently associated with organ space SSIs development alone, while sustaining blast injuries were associated with reduced likelihood.

CONCLUSION

Despite severity of injuries and the battlefield environment, the combat casualty laparotomy SSI rate is relatively low at 14%, with similar risk factors and rates reported following severe civilian trauma.

LEVEL OF EVIDENCE

Epidemiological, level III.

Role of albumin on endothelial basement membrane and hemostasis in a rat model of hemorrhagic shock

BACKGROUND

We sought to determine the extent of loss of endothelial basement membrane (BM), leukocyte recruitment, and changes in coagulation after hemorrhagic shock, followed by limited-volume resuscitation (LVR) with 5% albumin (ALB).

METHODS

Anesthetized rats were bled 40% of blood volume and assigned to treatment groups: untreated (n = 6), LVR with normal saline (NS; n = 8), or LVR with ALB (n = 8). Sham rats (n = 6) underwent all procedures except hemorrhage or resuscitation. Blood samples were assayed for active proteases, such as metalloproteinase 9 (MMP-9) and a disintegrin and metalloproteinase 10 (ADAM-10), BM-type heparan sulfate proteoglycan (perlecan), cell count, and coagulation function. Leukocyte transmigration was used to estimate the net efficiency of leukocyte recruitment in cremaster venules.

RESULTS

Hemorrhage significantly lowered red cell count, but white cell and platelet counts did not change (vs. sham). Ionized calcium in plasma was significantly reduced in untreated and remained so after NS. In contrast, ionized calcium was normalized after ALB. Plasma expansion after NS and ALB further reduced leukocyte and platelet counts. Metalloproteinase 9, ADAM-10, and perlecan were significantly higher in untreated rats (vs. sham). Albumin normalized MMP-9, ADAM-10, and perlecan levels, while NS further increased MMP-9, ADAM-10, and perlecan (vs. sham). Transmigrated leukocytes doubled in the untreated group and remained elevated after NS (vs. sham) but normalized after ALB. Albumin reduced every stage of the leukocyte recruitment process to sham levels.

CONCLUSION

Despite similar plasma expansion, NS weakened platelet function contrary to ALB. Plasma expansion with ALB resulted in restoration of BM integrity and attenuation of leukocyte recruitment to tissues, in contrast to NS. Albumin plays a critical role in restoring BM integrity, attenuating leukocyte recruitment to tissues, and optimizing hemostasis by increasing ionized calcium in plasma.

Resuscitative Strategies to Modulate the Endotheliopathy of Trauma: From Cell to Patient

Clinical data has supported the early use of plasma in high ratios of plasma to red cells to patients in hemorrhagic shock. The benefit from plasma seems to extend beyond its hemostatic effects to include protection to the post-shock dysfunctional endothelium. Resuscitation of the endothelium by plasma and one of its major constituents, fibrinogen, involves cell surface stabilization of syndecan-1, a transmembrane proteoglycan and the protein backbone of the endothelial glycocalyx. The pathogenic role of miRNA-19b to the endothelium is explored along with the PAK-1-mediated intracellular pathway that may link syndecan-1 to cytoskeletal protection. Additionally, clinical studies using fibrinogen and cyroprecipitate to aid in hemostasis of the bleeding patient are reviewed and new data to suggest a role for plasma and its byproducts to treat the dysfunctional endothelium associated with nonbleeding diseases is presented.

Bioelectrical impedance analysis-guided fluid management promotes primary fascial closure after open abdomen: a randomized controlled trial

BACKGROUND

Fluid overload (FO) after resuscitation is frequent and contributes to adverse outcomes among postinjury open abdomen (OA) patients. Bioelectrical impedance analysis (BIA) is a promising tool for monitoring fluid status and FO. Therefore, we sought to investigate the efficacy of BIA-directed fluid resuscitation among OA patients.

METHODS

A pragmatic, prospective, randomized, observer-blind, single-center trial was performed for all trauma patients requiring OA between January 2013 and December 2017 to a national referral center. A total of 140 postinjury OA patients were randomly assigned in a 1:1 ratio to receive either a BIA-directed fluid resuscitation (BIA) protocol that included fluid administration with monitoring of hemodynamic parameters and different degrees of interventions to achieve a negative fluid balance targeting the hydration level (HL) measured by BIA or a traditional fluid resuscitation (TRD) in which clinicians determined the fluid resuscitation regimen according to traditional parameters during 30 days of ICU management. The primary outcome was the 30-day primary fascial closure (PFC) rate. The secondary outcomes included the time to PFC, postoperative 7-day cumulative fluid balance (CFB) and adverse events within 30 days after OA. The Kaplan-Meier method and the log-rank test were utilized for PFC after OA. A generalized linear regression model for the time to PFC and CFB was built.

RESULTS

A total of 134 patients completed the trial (BIA, n = 66; TRD, n = 68). The BIA patients were significantly more likely to achieve PFC than the TRD patients (83.33% vs. 55.88%, P < 0.001). In the BIA group, the time to PFC occurred earlier than that of the TRD group by an average of 3.66 days (P < 0.001). Additionally, the BIA group showed a lower postoperative 7-day CFB by an average of 6632.80 ml (P < 0.001) and fewer complications.

CONCLUSION

Among postinjury OA patients in the ICU, the use of BIA-guided fluid resuscitation resulted in a higher PFC rate and fewer severe complications than the traditional fluid resuscitation strategy.

Battlefield Medicine: Anesthesia and Critical Care in the Combat Zone

The US Military Joint Trauma System has been developed to mitigate the harsh conditions under which medical providers care for combat casualties and provide continuity of care from the battlefield to US medical centers. We review the components of this system with emphasis on combat trauma care under fire and the role of the anesthesiologist and intensivist in this continuum of care. An important link in the chain of survival is the Air Force Critical Care Aeromedical Transport Team, which provides critical care while transporting casualties from the theater to higher levels of care outside the war zone and home.

Cryoprecipitate attenuates the endotheliopathy of trauma in mice subjected to hemorrhagic shock and trauma

BACKGROUND

Plasma has been shown to mitigate the endotheliopathy of trauma. Protection of the endothelium may be due in part to fibrinogen and other plasma-derived proteins found in cryoprecipitate; however, the exact mechanisms remain unknown. Clinical trials are underway investigating early cryoprecipitate administration in trauma. In this study, we hypothesize that cryoprecipitate will inhibit endothelial cell (EC) permeability in vitro and will replicate the ability of plasma to attenuate pulmonary vascular permeability and inflammation induced by hemorrhagic shock and trauma (HS/T) in mice.

METHODS

In vitro, barrier permeability of ECs subjected to thrombin challenge was measured by transendothelial electrical resistance. In vivo, using an established mouse model of HS/T, we compared pulmonary vascular permeability among mice resuscitated with (1) lactated Ringer's solution (LR), (2) fresh frozen plasma (FFP), or (3) cryoprecipitate. Lung tissue from the mice in all groups was analyzed for markers of vascular integrity, inflammation, and inflammatory gene expression via NanoString messenger RNA quantification.

RESULTS

Cryoprecipitate attenuates EC permeability and EC junctional compromise induced by thrombin in vitro in a dose-dependent fashion. In vivo, resuscitation of HS/T mice with either FFP or cryoprecipitate attenuates pulmonary vascular permeability (sham, 297 ± 155; LR, 848 ± 331; FFP, 379 ± 275; cryoprecipitate, 405 ± 207; p < 0.01, sham vs. LR; p < 0.01, LR vs. FFP; and p < 0.05, LR vs. cryoprecipitate). Lungs from cryoprecipitate- and FFP-treated mice demonstrate decreased lung injury, decreased infiltration of neutrophils and activation of macrophages, and preserved pericyte-endothelial interaction compared with LR-treated mice. Gene analysis of lung tissue from cryoprecipitate- and FFP-treated mice demonstrates decreased inflammatory gene expression, in particular, IL-1β and NLRP3, compared with LR-treated mice.

CONCLUSION

Our data suggest that cryoprecipitate attenuates the endotheliopathy of trauma in HS/T similar to FFP. Further investigation is warranted on active components and their mechanisms of action.

Trauma Laparotomy in the UK: A Prospective National Service Evaluation

BACKGROUND

Trauma patients requiring abdominal operation have considerable morbidity and mortality, yet no specific quality indicators are measured in the trauma systems of the UK. The aims of this study were to describe the characteristics and outcomes of patients undergoing emergency abdominal operation and key processes of care.

STUDY DESIGN

A prospective multicenter service evaluation was conducted within all of the major trauma centers in the UK. The study was conducted during 6 months beginning in January 2019. Patients of any age undergoing laparotomy or laparoscopy within 24 hours of injury were included. Existing standards for related emergent conditions were used.

RESULTS

The study included 363 patients from 34 hospitals. The majority were young men with no comorbidities who required operation to control bleeding (51%). More than 90% received attending-delivered care in the emergency department (318 of 363) and operating room (321 of 363). The overall mortality rate was 9%. Patients with blunt trauma had a greater risk of death compared with patients with penetrating injuries (16.6% vs 3.8%; risk ratio 4.3; 95% CI, 2.0 to 9.4). Patients in which the Major Hemorrhage Protocol (MHP) was activated and who received a blood transfusion (n = 154) constituted a high-risk subgroup, accounting for 45% of the study cohort but 97% of deaths and 96% of blood components transfused. The MHP subgroup had expedited timelines from emergency department arrival to knife to skin (MHP: median 119 minutes [interquartile range 64 to 218 minutes] vs no MHP: median 211 minutes [interquartile range 135 to 425 minutes]; p < 0.001).

CONCLUSIONS

The majority of trauma patients requiring emergency abdominal operation received a high standard of expedited care in a maturing national trauma system. Despite this, mortality and resource use among high-risk patients remains considerable.

Direct Peritoneal Resuscitation Improves Survival in a Murine Model of Combined Hemorrhage and Burn Injury

INTRODUCTION

Combined burn injury and hemorrhagic shock are a common cause of injury in wounded warfighters. Current protocols for resuscitation for isolated burn injury and isolated hemorrhagic shock are well defined, but the optimal strategy for combined injury is not fully established. Direct peritoneal resuscitation (DPR) has been shown to improve survival in rats after hemorrhagic shock, but its role in a combined burn/hemorrhage injury is unknown. We hypothesized that DPR would improve survival in mice subjected to combined burn injury and hemorrhage.

MATERIALS AND METHODS

Male C57/BL6J mice aged 8 weeks were subjected to a 7-second 30% total body surface area scald in a 90°C water bath. Following the scald, mice received DPR with 1.5 mL normal saline or 1.5 mL peritoneal dialysis solution (Delflex). Control mice received no peritoneal solution. Mice underwent a controlled hemorrhage shock via femoral artery cannulation to a systolic blood pressure of 25 mm Hg for 30 minutes. Mice were then resuscitated to a target blood pressure with either lactated Ringer's (LR) or a 1:1 ratio of packed red blood cells (pRBCs) and fresh frozen plasma (FFP). Mice were observed for 24 hours following injury.

RESULTS

Median survival time for mice with no DPR was 1.47 hours in combination with intravascular LR resuscitation and 2.08 hours with 1:1 pRBC:FFP. Median survival time significantly improved with the addition of intraperitoneal normal saline or Delflex. Mice that received DPR followed by 1:1 pRBC:FFP required less intravascular volume than mice that received DPR with LR, pRBC:FFP alone, and LR alone. Intraperitoneal Delflex was associated with higher levels of tumor necrosis factor alpha and macrophage inflammatory protein 1 alpha and lower levels of interleukin 10 and intestinal fatty acid binding protein. Intraperitoneal normal saline resulted in less lung injury 1 hour postresuscitation, but increased to similar severity of Delflex at 4 hours.

CONCLUSIONS

After a combined burn injury and hemorrhage, DPR leads to increased survival in mice. Survival was similar with the use of normal saline or Delflex. DPR with normal saline reduced the inflammatory response seen with Delflex and delayed the progression of acute lung injury. DPR may be a valuable strategy in the treatment of patients with combined burn injury and hemorrhage.

Is fresh, leucodepleted, whole blood transfusion superior to blood component transfusion in pediatric patients undergoing spinal deformity surgeries? A prospective, randomized study analyzing postoperative serological parameters and clinical recovery

Purpose

To compare the effectiveness of fresh whole blood (FWB) and blood component transfusion in improving clinical outcome and serological parameters in the early postoperative period following spinal deformity surgery.

Methods

Patients undergoing major spinal deformity surgeries involving ≥ 6 levels of fusion and expected blood loss ≥ 750 ml between September 2017 and August 2018 were included in the study. The patients were randomized into two groups: FWBG and CG, receiving fresh whole blood and component transfusions, respectively.

Results

A total of 65 patients with spinal deformities of different etiologies were included. The mean age was 14.0 and 14.9 years in FWB and CG, respectively. All other preoperative parameters were comparable. The mean fusion levels and surgical time were 11.1 and 221.20 min in FWB, as compared with 10.70 and 208.74minutes in CG, respectively. Intraoperative blood losses were 929 ml (FWBG) and 847 ml(CG), and the mean volumes of transfusion were 1.90 (FWBG) and 1.65 units (CG). FWBG was significantly superior to CG in the following clinical and laboratory parameters: duration of oxygen dependence [36.43 (FWBG) vs. 43.45 h (CG); P = 0.0256], mean arterial pH [7.442 (FWBG) vs. 7.394 (CG); p < 0.001], interleukin-6 [30.04 (FWBG) vs. 35.10 (CG); p < 0.019], mean duration of HDU stay [40.6 hours (FWBG) vs 46.51 hours (CG); p = 0.0234] and postoperative facial puffiness [7/30 in FWBG vs. 18/35 (CG) (P < 0.02)].

Conclusion

FWB transfusion can potentially improve the immediate postoperative outcome in patients undergoing major spinal deformity surgeries by reducing the duration of intensive care unit stay and oxygen dependence. The other potential benefits of this practice, based on our study, include a reduced inflammatory response (reduced lactate and IL-6) and postoperative facial puffiness. However, further large-scale validation studies in future are necessary to precisely determine the role of FWB in spine surgeries.

Level of evidence II

Diagnostic: individual cross-sectional studies with the consistently applied reference standard and blinding.

Dynamic impact of transfusion ratios on outcomes in severely injured patients: Targeted machine learning analysis of the Pragmatic, Randomized Optimal Platelet and Plasma Ratios randomized clinical trial

BACKGROUND

Massive transfusion protocols to treat postinjury hemorrhage are based on predefined blood product transfusion ratios followed by goal-directed transfusion based on patient's clinical evolution. However, it remains unclear how these transfusion ratios impact patient outcomes over time from injury.

METHODS

The Pragmatic, Randomized Optimal Platelet and Plasma Ratios (PROPPR) is a phase 3, randomized controlled trial, across 12 Level I trauma centers in North America. From 2012 to 2013, 680 severely injured patients required massive transfusion. We used semiparametric machine learning techniques and causal inference methods to augment the intent-to-treat analysis of PROPPR, estimating the dynamic relationship between transfusion ratios and outcomes: mortality and hemostasis at different timepoints during the first 24 hours after admission.

RESULTS

In the intention-to-treat analysis, the 1:1:1 group tended to have decreased mortality, but with no statistical significance. For patients in whom hemostasis took longer than 2 hours, the 1:1:1 ratio was associated with a higher probability of hemostasis, statistically significant from the 4 hour on. In the per-protocol, actual-transfusion-ratios-received analysis, during four successive time intervals, no significant association was found between the actual ratios and mortality. When comparing patient groups who received both high plasma/PRBC and high platelet/PRBC ratios to the group of low ratios in both, the relative risk of achieving hemostasis was 2.49 (95% confidence interval, 1.19-5.22) during the third hour after admission, suggesting a significant beneficial impact of higher transfusion ratios of plasma and platelets on hemostasis.

CONCLUSION

Our results suggest that the impact of transfusion ratios on hemostasis is dynamic. Overall, the transfusion ratios had no significant impact on mortality over time. However, receiving higher ratios of platelets and plasma relative to red blood cells hastens hemostasis in subjects who have yet to achieve hemostasis within 3 hours after hospital admission.

LEVEL OF EVIDENCE

Therapeutic IV.