Injury Severity, Arrival Physiology, Coagulopathy, and Outcomes Among the Youngest Trauma Patients

BACKGROUND

Although physiologic differences exist between younger and older children, pediatric trauma analyses are weighted toward older patients. Trauma-induced coagulopathy, determined by rapid thrombelastography (rTEG), is a predictor of outcome in trauma patients, but the significance of rTEG values among very young trauma patients remains unknown. Our objective was to identify the prehospital or physiologic factors, including rTEG values, that were associated with mortality in trauma patients younger than 5 y old.

MATERIALS AND METHODS

Patients younger than 5 y old that met the highest-level trauma activation criteria at an academic children's hospital from 2010-2016 were included. Data regarding demographics, pre-hospital management, laboratory values, injury severity, and outcome were queried. Univariate and multivariate analyses were performed comparing survivors and non-survivors.

RESULTS

A total of 356 patients were included. 60% were male, and the median age was 3 y (IQR 1-4). Overall mortality was 13% (n = 45); brain injury (91%) and hemorrhage (9%) were the causes of death. Compared to survivors, rTEG values in nonsurvivors showed longer activated clotting time and slower speed of clot formation. Clot strength was also decreased in nonsurvivors. On stepwise regression modeling, rTEG values were not significant predictors of mortality. Admission base deficit, arrival temperature, and head injury severity were identified as independent predictors of mortality.

CONCLUSIONS

While rTEG identified coagulopathy in trauma patients < 5 y old, it was not an independent predictor of mortality. Our findings suggest that trauma providers should pay close attention to admission base deficit, arrival temperature, and head injury severity when managing the youngest trauma patients.

The prehospital use of younger age whole blood is associated with an improved arrival coagulation profile

INTRODUCTION

Recent in vitro data have shown that the hemostatic profile of whole blood (WB) degrades significantly after 14 days, yet the optimal storage remains debated. We hypothesized that arrival coagulation studies would be improved in patients receiving younger WB in the prehospital setting.

METHODS

This study was approved by our institutional institutional review board. We evaluated all trauma patients who received prehospital blood products by our helicopter service between July 2017 and July 2019. "Young" WB was defined as 14 days or less. Patients who received at least 1 U of young WB were classified as YOUNG, while the remainder was classified as OLD. Continuous data are presented as medians (25th-75th interquartile range) with comparisons performed using Wilcoxon rank sum. Assessments of clinical hemostatic potential included arrival platelet cell count and rapid thrombelastography. Multivariate regression analysis was also performed (Stata 12.1; College Station, TX).

RESULTS

A total of 220 patients received prehospital WB during the study period. Of these, 153 patients received YOUNG WB, while 67 were transfused only OLD WB units. There were no differences in demographics, prehospital or arrival physiology, or Injury Severity Score among the two groups. The measures of clot initiation (activated clotting time) and kinetics (k time) were improved, as were the measures of clot acceleration/fibrinogen function (angle) and platelet function (maximum amplitude). As well, arrival platelet count was higher in the YOUNG cohort. No significant differences in postarrival transfusion were noted (p = 0.220). Multivariate analysis showed the greatest differences in maximum amplitude and α angle but failed to reach significance.

CONCLUSION

Previous in vitro data have suggested deterioration of platelet function in cold-stored WB after 14 days. The current study demonstrated decreased global hemostasis by clinically available laboratory tests, especially related to fibrinogen and platelet interactions on univariate, but not multivariate analysis. This did not translate into increased transfusion requirements. Further studies are needed to determine the optimal storage duration for cold-stored WB for transfusion in the bleeding trauma patient, as well as rule out the presence of confounding variables.

LEVEL OF EVIDENCE

Therapeutic, level IV.

The Impact of Rapid Infuser Use on the Platelet Count, Platelet Function, and Hemostatic Potential of Whole Blood

BACKGROUND

Rapid infusion pumps employing filters, roller pumps, and heat exchangers for the administration of blood products are not approved for platelets or cryoprecipitate. This technology may decrease platelet count and degrade coagulation proteins. The effect of rapid infusers on the hemostatic potential of whole blood is unknown.

METHODS

Five units of low titer O+ whole blood were obtained from anonymous donors. Each unit was subjected to infusion by five different techniques: (1) gravity infusion without a filter, (2) gravity infusion with a filter, (3) Belmont rapid infuser at 70 mL/min, (4) Belmont at 100 mL/min, and (5) pressurized infusion with a pneumatic pressure bag and filter. After infusion, platelet count, platelet function, thrombin generation, and hemostatic potential were measured for each aliquot. Infusion techniques were compared, using gravity infusion without a filter as the control.

RESULTS

There was a significant decrease in platelet count from baseline (168,000) in the BELMONT70 (97,000) and BELMONT100 (94,000) groups (P < 0.05). However, there were no differences in platelet function (all P > 0.20). While there were no differences in thromboelastography parameters between control and infusion models (all P > 0.20), there were significant increases in thrombin generation parameters by CAT in both the BELMONT70 and BELMONT100 groups (all P < 0.05).

CONCLUSIONS

The use of a rapid infuser decreases the platelet count of WB but does not decrease platelet function or overall hemostatic potential. In fact, thrombin generation and thrombin potential are actually increased. Rapid infusers are safe for the transfusion of WB.

Different strokes: differences in the characteristics and outcomes of BCVI and non-BCVI strokes in trauma patients

Background

Although strokes are rare in trauma patients, they are associated with worse functional and cognitive outcomes and decreased mobility. Blunt cerebrovascular injury (BCVI)–related strokes and mortality have decreased, likely due to refined screening and treatment algorithms in trauma literature; however, there is a paucity of research addressing non-BCVI strokes in trauma. The purpose of this study is to evaluate the incidence, etiology, and risk factors of stroke in our trauma population in order to identify preventive strategies.

Methods

This study was a retrospective review of all adult trauma patients admitted to a level 1 trauma hospital who suffered a stroke during trauma admission from 2010 to 2017. Data were collected from the prospectively maintained trauma and stroke databases. Stroke etiology was determined by a vascular neurologist.

Results

Of the 43 674 adult trauma patients admitted during the study period, 99 (0.2%) were diagnosed with a stroke during the index admission. Twenty-one (21%) strokes were due to BCVI. Seventy-eight (79%) strokes were due to non-BCVI etiologies. Patients with non-BCVI strokes were older, less severely injured, and had more medical comorbidities compared with patients with a BCVI stroke. While patients with a BCVI stroke were more likely to suffer multiple traumatic injuries from MVC (76% vs 28%, p<0.001), non-BCVI strokes had more isolated extremity injuries from fall mechanism (55% vs 10%, p<0.001). Over the study period, the age and incidence of stroke and BCVI (p<0.001) increased. However, the rate of BCVI strokes decreased while the rate of non-BCVI strokes increased.

Discussion

The incidence of stroke has increased despite aggressive screening and treatment of BCVI. This increase is primarily due to non-BCVI strokes which are associated with advanced age and medical comorbidities after low mechanism traumatic injury. Medical optimization of comorbid conditions during trauma hospitalization will become increasingly important for stroke prevention as the population ages.

Level of evidence: Level III

Effect of Out-of-Hospital Tranexamic Acid vs Placebo on 6-Month Functional Neurologic Outcomes in Patients With Moderate or Severe Traumatic Brain Injury

IMPORTANCE

Traumatic brain injury (TBI) is the leading cause of death and disability due to trauma. Early administration of tranexamic acid may benefit patients with TBI.

OBJECTIVE

To determine whether tranexamic acid treatment initiated in the out-of-hospital setting within 2 hours of injury improves neurologic outcome in patients with moderate or severe TBI.

DESIGN, SETTING, AND PARTICIPANTS

Multicenter, double-blinded, randomized clinical trial at 20 trauma centers and 39 emergency medical services agencies in the US and Canada from May 2015 to November 2017. Eligible participants (N = 1280) included out-of-hospital patients with TBI aged 15 years or older with Glasgow Coma Scale score of 12 or less and systolic blood pressure of 90 mm Hg or higher.

INTERVENTIONS

Three interventions were evaluated, with treatment initiated within 2 hours of TBI: out-of-hospital tranexamic acid (1 g) bolus and in-hospital tranexamic acid (1 g) 8-hour infusion (bolus maintenance group; n = 312), out-of-hospital tranexamic acid (2 g) bolus and in-hospital placebo 8-hour infusion (bolus only group; n = 345), and out-of-hospital placebo bolus and in-hospital placebo 8-hour infusion (placebo group; n = 309).

MAIN OUTCOMES AND MEASURES

The primary outcome was favorable neurologic function at 6 months (Glasgow Outcome Scale-Extended score >4 [moderate disability or good recovery]) in the combined tranexamic acid group vs the placebo group. Asymmetric significance thresholds were set at 0.1 for benefit and 0.025 for harm. There were 18 secondary end points, of which 5 are reported in this article: 28-day mortality, 6-month Disability Rating Scale score (range, 0 [no disability] to 30 [death]), progression of intracranial hemorrhage, incidence of seizures, and incidence of thromboembolic events.

RESULTS

Among 1063 participants, a study drug was not administered to 96 randomized participants and 1 participant was excluded, resulting in 966 participants in the analysis population (mean age, 42 years; 255 [74%] male participants; mean Glasgow Coma Scale score, 8). Of these participants, 819 (84.8%) were available for primary outcome analysis at 6-month follow-up. The primary outcome occurred in 65% of patients in the tranexamic acid groups vs 62% in the placebo group (difference, 3.5%; [90% 1-sided confidence limit for benefit, -0.9%]; P = .16; [97.5% 1-sided confidence limit for harm, 10.2%]; P = .84). There was no statistically significant difference in 28-day mortality between the tranexamic acid groups vs the placebo group (14% vs 17%; difference, -2.9% [95% CI, -7.9% to 2.1%]; P = .26), 6-month Disability Rating Scale score (6.8 vs 7.6; difference, -0.9 [95% CI, -2.5 to 0.7]; P = .29), or progression of intracranial hemorrhage (16% vs 20%; difference, -5.4% [95% CI, -12.8% to 2.1%]; P = .16).

CONCLUSIONS AND RELEVANCE

Among patients with moderate to severe TBI, out-of-hospital tranexamic acid administration within 2 hours of injury compared with placebo did not significantly improve 6-month neurologic outcome as measured by the Glasgow Outcome Scale-Extended.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01990768.

Predicting the need for massive transfusion in the prehospital setting

INTRODUCTION

Massive transfusion (MT) prediction scores allowed for the early identification of patients with massive hemorrhage likely to require large volumes of blood products. Despite their utility, very few MT scoring systems have shown promise in the pre-hospital setting due to their complexity and resource limitations.

AREAS COVERED

Pub med database was utilized to identify supporting literature for this review which discusses the importance of blood-based resuscitation and highlights the utility of scoring systems to predict the need of massive transfusion. MTP scoring systems effective in the prehospital setting are specifically discussed.

EXPERT OPINION

Massive transfusions scores are useful in alerting hospitals to the severity of trauma patients and organizing resources necessary for appropriate patient care but should not completely replace clinical . The opportunity exists to extend their use to the pre-hospital setting to allow for even earlier notification and to triage patients to trauma centers best able to treat severely injured.

Artificial neural networks can predict trauma volume and acuity regardless of center size and geography: A multicenter study

BACKGROUND

Trauma has long been considered unpredictable. Artificial neural networks (ANN) have recently shown the ability to predict admission volume, acuity, and operative needs at a single trauma center with very high reliability. This model has not been tested in a multicenter model with differing climate and geography. We hypothesize that an ANN can accurately predict trauma admission volume, penetrating trauma admissions, and mean Injury Severity Score (ISS) with a high degree of reliability across multiple trauma centers.

METHODS

Three years of admission data were collected from five geographically distinct US Level I trauma centers. Patients with incomplete data, pediatric patients, and primary thermal injuries were excluded. Daily number of traumas, number of penetrating cases, and mean ISS were tabulated from each center along with National Oceanic and Atmospheric Administration data from local airports. We trained a single two-layer feed-forward ANN on a random majority (70%) partitioning of data from all centers using Bayesian Regularization and minimizing mean squared error. Pearson's product-moment correlation coefficient was calculated for each partition, each trauma center, and for high- and low-volume days (>1 standard deviation above or below mean total number of traumas).

RESULTS

There were 5,410 days included. There were 43,380 traumas, including 4,982 penetrating traumas. The mean ISS was 11.78 (SD = 6.12). On the training partition, we achieved R = 0.8733. On the testing partition (new data to the model), we achieved R = 0.8732, with a combined R = 0.8732. For high- and low-volume days, we achieved R = 0.8934 and R = 0.7963, respectively.

CONCLUSION

An ANN successfully predicted trauma volumes and acuity across multiple trauma centers with very high levels of reliability. The correlation was highest during periods of peak volume. This can potentially provide a framework for determining resource allocation at both the trauma system level and the individual hospital level.

LEVEL OF EVIDENCE

Care Management, level IV.

Age-Dependent Association of Occult Hypoperfusion and Outcomes in Trauma

BACKGROUND

Occult hypoperfusion (OH), or global hypoperfusion with normal vital signs, is a risk factor for poor outcomes in elderly trauma patients. We hypothesized that OH is associated with worse outcomes than shock in both young and elderly trauma patients.

METHODS

We conducted a single-center cohort study of adult (16 years or older) trauma patients from 2016 to 2018 with base excess measured on arrival. Perfusion states were defined as shock if heart rate was >120 beats/min or systolic blood pressure was <90 mmHg; OH if base excess was < -2 mmol/L, heart rate was <120 beats/min, and systolic blood pressure was >90 mmHg; and normal for all others. Patients were stratified as young (younger than 55 years) or elderly (55 years or older). Bayesian regression was used to assess the relationship between arrival perfusion state and mortality or serious complication.

RESULTS

Of 3,126 included patients, 808 were elderly. Rates of shock (33% and 31%) and OH (25% and 23%) were similar in young and elderly patients, respectively. OH on arrival was associated with higher odds of mortality or serious complication than normal perfusion, regardless of age group. Compared with shock, OH was associated with an odds ratio of 1.21 (95% CI, 0.97 to 1.52, posterior probability 96%) for poor outcomes in elderly patients and an odds ratio of 0.52 (95% CI, 0.42 to 0.65, posterior probability <1%) for poor outcomes in younger patients. Findings were similar on sensitivity analysis, excluding shock patients with base excess ≥ -2 mmol/L.

CONCLUSIONS

In elderly but not younger patients, OH is associated with worse outcomes than shock. Although shock parameters might need to be redefined in elderly patients, more attention is necessary for the diagnosis and treatment of all hypoperfused states in this age group.

Supplementation with antithrombin III ex vivo optimizes enoxaparin responses in critically injured patients

BACKGROUND

The high incidence of venous thromboembolism (VTE) following trauma persists in spite of aggressive thromboprophylaxis strategies. Approximately half of VTE patients do not achieve the recommended anti-FXa response to enoxaparin anticoagulation (0.1-0.4 IU/mL), however, research to explain or correct this phenomenon is lacking. We hypothesized that antithrombin III (AT) deficiency is associated with poor enoxaparin responsiveness in trauma patients that develop VTE which can be reversed through supplementation with AT.

METHODS AND FINDINGS

A retrospective cohort study was performed on plasma collected from trauma patients who did and did not develop pulmonary embolism (PE) as well as healthy volunteers. AT levels, thrombin generation, and anti-FXa levels were measured in the collected plasma at baseline and in response to supplementation with AT concentrate at 120-200% or plasma (30% volume). A total of 54 PE patients and 46 non-PE patients were enrolled in this study for analysis. Compared to healthy volunteers, trauma patients had lower levels of AT, elevated thrombin generation, and lower anti-FXa levels in response to enoxaparin. Moreover, thrombin generation was higher and responses to enoxaparin were lower in patients who developed PE compared to those who did not develop PE. We found that supplementation with AT, but not plasma, increased AT levels and improved enoxaparin-mediated inhibition of thrombin generation.

CONCLUSIONS

Supplementation with AT may provide a novel adjunct therapy to increase the effectiveness of enoxaparin thromboprophylaxis and reduce the incidence of VTE in the trauma population.

Procoagulant in vitro effects of clinical cellular therapeutics in a severely injured trauma population

Clinical trials in trauma populations are exploring the use of clinical cellular therapeutics (CCTs) like human mesenchymal stromal cells (MSC) and mononuclear cells (MNC). Recent studies demonstrate a procoagulant effect of these CCTs related to their expression of tissue factor (TF). We sought to examine this relationship in blood from severely injured trauma patients and identify methods to reverse this procoagulant effect. Human MSCs from bone marrow, adipose, and amniotic tissues and freshly isolated bone marrow MNC samples were tested. TF expression and phenotype were quantified using flow cytometry. CCTs were mixed individually with trauma patients' whole blood, assayed with thromboelastography (TEG), and compared with healthy subjects mixed with the same cell sources. Heparin was added to samples at increasing concentrations until TEG parameters normalized. Clotting time or R time in TEG decreased relative to the TF expression of the CCT treatment in a logarithmic fashion for trauma patients and healthy subjects. Nonlinear regression curves were significantly different with healthy subjects demonstrating greater relative decreases in TEG clotting time. In vitro coadministration of heparin normalized the procoagulant effect and required dose escalation based on TF expression. TF expression in human MSC and MNC has a procoagulant effect in blood from trauma patients and healthy subjects. The procoagulant effect is lower in trauma patients possibly because their clotting time is already accelerated. The procoagulant effect due to MSC/MNC TF expression could be useful in the bleeding trauma patient; however, it may emerge as a safety release criterion due to thrombotic risk. The TF procoagulant effect is reversible with heparin.

Extracorporeal life support in pediatric trauma: a systematic review

Introduction

Extracorporeal membrane oxygenation (ECMO) was once thought to be contraindicated in trauma patients, however ECMO is now used in adult patients with post-traumatic acute respiratory distress syndrome (ARDS) and multisystem trauma. Despite acceptance as a therapy for the severely injured adult, there is a paucity of evidence supporting ECMO use in pediatric trauma patients.

Methods

An electronic literature search of PubMed, MEDLINE, and the Cochrane Database of Collected Reviews from 1972 to 2018 was performed. Included studies reported on ECMO use after trauma in patients ≤18 years of age and reported outcome data. The Institute of Health Economics quality appraisal tool for case series was used to assess study quality.

Results

From 745 studies, four met inclusion criteria, reporting on 58 pediatric trauma patients. The age range was <1–18 years. Overall study quality was poor with only a single article of adequate quality. Twenty-nine percent of patients were cannulated at adult centers, the remaining at pediatric centers. Ninety-one percent were cannulated for ARDS and the remaining for cardiovascular collapse. Overall 60% of patients survived and the survival rate ranged from 50% to 100%. Seventy-seven percent underwent venoarterial cannulation and the remaining underwent veno-venous cannulation.

Conclusion

ECMO may be a therapeutic option in critically ill pediatric trauma patients. Consideration should be made for the expansion of ECMO utilization in pediatric trauma patients including its application for pediatric patients at adult trauma centers with ECMO capabilities.

Fibrinolysis Shutdown in Trauma: Historical Review and Clinical Implications

Despite over a half-century of recognizing fibrinolytic abnormalities after trauma, we remain in our infancy in understanding the underlying mechanisms causing these changes, resulting in ineffective treatment strategies. With the increased utilization of viscoelastic hemostatic assays (VHAs) to measure fibrinolysis in trauma, more questions than answers are emerging. Although it seems certain that low fibrinolytic activity measured by VHA is common after injury and associated with increased mortality, we now recognize subphenotypes within this population and that specific cohorts arise depending on the specific time from injury when samples are collected. Future studies should focus on these subtleties and distinctions, as hypofibrinolysis, acute shutdown, and persistent shutdown appear to represent distinct, unique clinical phenotypes, with different pathophysiology, and warranting different treatment strategies.

Whole Blood for Resuscitation in Adult Civilian Trauma in 2017: A Narrative Review

After a hiatus of several decades, the concept of cold whole blood (WB) is being reintroduced into acute clinical trauma care in the United States. Initial implementation experience and data grew from military medical applications, followed by more recent development and data acquisition in civilian institutions. Anesthesiologists, especially those who work in acute trauma facilities, are likely to be presented with patients either receiving WB from the emergency department or may have WB as a therapeutic option in massive transfusion situations. In this focused review, we briefly discuss the historical concept of WB and describe the characteristics of WB, including storage, blood group compatibility, and theoretical hemolytic risks. We summarize relevant recent retrospective military and preliminary civilian efficacy as well as safety data related to WB transfusion, and describe our experience with the initial implementation of WB transfusion at our level 1 trauma hospital. Suggestions and collective published experience from other centers as well as ours may be useful to those investigating such a program. The role of WB as a significant therapeutic option in civilian trauma awaits further prospective validation.

Can trauma surgeons keep up? A prospective cohort study comparing outcomes between patients with traumatic brain injury cared for in a trauma versus neuroscience intensive care unit

Background

Although many patients with traumatic brain injury (TBI) are admitted to trauma intensive care units (ICUs), some question whether outcomes would improve if their care was provided in neurocritical care units. We sought to compare characteristics and outcomes of patients with TBI admitted to and cared for in a trauma versus neuroscience ICU.

Methods

We conducted a prospective cohort study of adult (≥18 years of age) blunt trauma patients with TBI admitted to a trauma versus neuroscience ICU between May 2015 and December 2016. We used multivariable logistic regression to estimate an adjusted odds ratio (OR) comparing 30-day mortality between cohorts.

Results

In total, 548 patients were included in the study, including 207 (38%) who were admitted to the trauma ICU and 341 (62%) to the neuroscience ICU. When compared with neuroscience ICU admissions, patients admitted to the trauma ICU were more likely to have sustained their injuries from a high-speed mechanism (71% vs. 34%) and had a higher Injury Severity Score (ISS) (median 25 vs. 16) despite a similar head Abbreviated Injury Scale score (3 vs. 3, p=0.47) (all p<0.05). Trauma ICU patients also had a lower initial Glasgow Coma Scale score (5 vs. 15) and systolic blood pressure (128 mm Hg vs. 136 mm Hg) and were more likely to have fixed or unequal pupils at admission (13% vs. 8%) (all p<0.05). After adjusting for age, ISS, a high-speed mechanism of injury, fixed or unequal pupils at admission, and field intubation, the odds of 30-day mortality was 70% lower among patients admitted to the trauma versus neuroscience ICU (adjusted OR=0.30, 95% CI 0.11 to 0.82).

Conclusions

Despite a higher injury burden and worse neurological examination and hemodynamics at presentation, patients admitted to the trauma ICU had a lower adjusted 30-day mortality. This finding may relate to improved care of associated injuries in trauma versus neuroscience ICUs.

Level of evidence

Prospective comparative study, level II.

Risk Factors for the Development of Acute Respiratory Distress Syndrome Following Hemorrhage

BACKGROUND

The Pragmatic Randomized Optimal Platelet and Plasma Ratios (PROPPR) study evaluated the effects of plasma and platelets on hemostasis and mortality after hemorrhage. The pulmonary consequences of resuscitation strategies that mimic whole blood, remain unknown.

METHODS

A secondary analysis of the PROPPR study was performed. Injured patients predicted to receive a massive transfusion were randomized to 1:1:1 versus 1:1:2 plasma-platelet-red blood cell ratios at 12 Level I North American trauma centers. Patients with survival >24 h, an intensive care unit (ICU) stay, and a recorded PaO2/FiO2 (P/F) ratio were included. Acute respiratory distress syndrome (ARDS) was defined as a P/F ratio < 200, with bilateral pulmonary infiltrates, and adjudicated by investigators.

RESULTS

Four hundred fifty-four patients were reviewed (230 received 1:1:1, 224 1:1:2). Age, sex, injury mechanism, and regional abbreviated injury scale (AIS) scores did not differ between cohorts. Tidal volume, positive end-expiratory pressure, and lowest P/F ratio did not differ. No significant differences in ARDS rates (14.8% vs. 18.4%), ventilator-free (24 vs. 24) or ICU-free days (17.5 vs. 18), hospital length of stay (22 days vs. 18 days), or 30-day mortality were found (28% vs. 28%). ARDS was associated with blunt injury (OR 3.61 [1.53-8.81] P < 0.01) and increasing chest AIS (OR 1.40 [1.15-1.71] P < 0.01). Each 500 mL of crystalloid infused during hours 0 to 6 was associated with a 9% increase in the rate of ARDS (OR 1.09 [1.04-1.14] P < 0.01). Blood given at 0 to 6 or 7 to 24 h were not risk factors for lung injury.

CONCLUSION

Acute crystalloid exposure, but not blood products, is a potentially modifiable risk factor for the prevention of ARDS following hemorrhage.

Platelet transfusions improve hemostasis and survival in a substudy of the prospective, randomized PROPPR trial

Transfusing platelets during massive hemorrhage is debated because of a lack of high-quality evidence concerning outcomes in trauma patients. The objective of this study was to examine the effect of platelet transfusions on mortality in severely injured trauma patients. This work analyzed PROPPR (Pragmatic, Randomized Optimal Platelet and Plasma Ratios) trial patients who received only the first cooler of blood products, which either did or did not contain platelets. Primary outcomes were all-cause mortality at 24 hours and 30 days and hemostasis. Secondary outcomes included cause of death, complications, and hospital-, intensive care unit (ICU)-, and ventilator-free days. Continuous variables were compared using Wilcoxon rank sum tests. Categorical variables were compared using Fisher's exact tests. There were 261 PROPPR patients who achieved hemostasis or died before receiving a second cooler of blood products (137 received platelets and 124 did not). Patients who received platelets also received more total plasma (median, 3 vs 2 U; P < .05) by PROPPR intervention design. There were no differences in total red blood cell transfusions between groups. After controlling for plasma volume, patients who received platelets had significantly decreased 24-hour (5.8% vs 16.9%; P < .05) and 30-day mortality (9.5% vs 20.2%; P < .05). More patients in the platelet group achieved hemostasis (94.9% vs 73.4%; P < .01), and fewer died as a result of exsanguination (1.5% vs 12.9%; P < .01). Patients who received platelets had a shorter time on mechanical ventilation (P < .05); however, no differences in hospital- or ICU-free days were observed. In conclusion, early platelet administration is associated with improved hemostasis and reduced mortality in severely injured, bleeding patients. This trial was registered at www.clinicaltrials.gov as # NCT01545232.

The hyperfibrinolytic phenotype is the most lethal and resource intense presentation of fibrinolysis in massive transfusion patients

BACKGROUND

Among bleeding patients, we hypothesized that the hyperfibrinolytic (HF) phenotype would be associated with the highest mortality, whereas shutdown (SD) patients would have the greatest complication burden.

METHODS

Severely injured patients predicted to receive a massive transfusion at 12 Level I trauma centers were randomized to one of two transfusion ratios as described in the Pragmatic, Randomized, Optimal Platelet and Plasma Ratio trial. Fibrinolysis phenotypes were determined based on admission clot lysis at 30 minutes (LY30): SD ≤0.8%, physiologic (PHYS) 0.9-2.9%, and HF ≥3%. Univariate and multivariate analysis was performed. Logistic regression was used to adjust for age, gender, arrival physiology, shock, injury severity, center effect, and treatment arm.

RESULTS

Among the 680 patients randomized, 547(80%) had admission thrombelastography (TEG) values available to determine fibrinolytic phenotypes. Compared to SD and PHYS, HF patients had higher Injury Severity Score (25 vs. 25 vs. 34), greater base deficit (-8 vs. -6 vs. -12) and were more uniformly hypocoagulable on admission by PT, PTT, and TEG values; all p <0.001. HF patients also received more red blood cells, plasma, and platelets (at 3, 6, and 24 hours); had fewer ICU-, ventilator-, and hospital-free days; and had higher 24-hour and 30-day mortality. There were no differences in complications between the three phenotypes. Multivariate logistic regression demonstrated that HF on admission was associated with a threefold higher mortality (OR 3.06, 95% CI 1.57-5.95, p = 0.001).

CONCLUSIONS

Previous data have shown that both the SD and HF phenotypes are associated with increased mortality and complications in the general trauma population. However, in a large cohort of bleeding patients, HF was confirmed to be a much more lethal and resource-intense phenotype. These data suggest that further research into the understanding of SD and HF is warranted to improve outcomes in this patient population.

LEVEL OF EVIDENCE

Prognostic, level II.