A multicenter evaluation of whether gender dimorphism affects survival after trauma

EFFECT OF GENDER ON 28-DAY SURVIVAL RATES AND TRANSFUSION VOLUME IN SEVERE TRAUMA PATIENTS: A MULTICENTER OBSERVATIONAL STUDY

ABSTRACT

Background: This study clarified the relationship between sex with survival and transfusion volume in severe trauma cases. Methods: A multicenter, collaborative post hoc analysis of patients with trauma in Japan was conducted. Patients aged ≥18 years with severe trauma indicated by an Injury Severity Score (ISS) of 16 or higher were enrolled. Patients were matched and analyzed by gender based on propensity score with factors determined at the time of injury. Subgroup analysis was performed on patients younger than 50 years and older than 50 years. The significance level was defined as P < 0.05. Results: The 1,189 patients included in this registry were divided into adjusted groups of 226 male and female patients each. In the main analysis, 28-day survival rates in females were significantly higher than those in males ( P = 0.046). In the subgroup analyses, there was no statistically significant prognostic effect of gender. Secondary outcomes, including transfusion volume, showed no significant gender-based variations. Logistic regression analyses consistently demonstrated that female sex was a significant favorable prognostic factor in all ages. This was true for the over-50 group on subgroup analysis, but no significant gender-prognosis relationship was identified in the under-50 age group. High ISSs were associated with poorer outcomes across all age groups. Conclusion: In severe trauma, survival at 28 days was significantly lower in males. However, this trend was not observed in patients aged <50 years. Factors other than sex hormones may be responsible for differences in posttraumatic outcomes by gender.

The beneficial roles and mechanisms of estrogens in immune health and infection disease

Multiple epidemiologic studies have revealed that gender is considered one of the important factors in the frequency and severity of certain infectious diseases, in which estrogens may play a vital role. There is growing evidence that estrogens as female sex hormone can modulate multiple biological functions outside of the reproductive system, such as in brain and cardiovascular system. However, it is largely unknown about the roles and mechanisms of estrogens/estrogen receptors in immune health and infection disease. Thence, by reading a lot of literature, we summarized the regulatory mechanisms of estrogens/estrogen receptors in immune cells and their roles in certain infectious diseases with gender differences. Therefore, estrogens may have therapeutic potentials to prevent and treat these infectious diseases, which needs further clinical investigation.

Sex-related immunity: could Toll-like receptors be the answer in acute inflammatory response?

An increasing number of studies have highlighted the existence of a sex-specific immune response, wherein men experience a worse prognosis in cases of acute inflammatory diseases. Initially, this sex-dependent inflammatory response was attributed to the influence of sex hormones. However, a growing body of evidence has shifted the focus toward the influence of chromosomes rather than sex hormones in shaping these inflammatory sex disparities. Notably, certain pattern recognition receptors, such as Toll-like receptors (TLRs), and their associated immune pathways have been implicated in driving the sex-specific immune response. These receptors are encoded by genes located on the X chromosome. TLRs are pivotal components of the innate immune system, playing crucial roles in responding to infectious diseases, including bacterial and viral pathogens, as well as trauma-related conditions. Importantly, the TLR-mediated inflammatory responses, as indicated by the production of specific proteins and cytokines, exhibit discernible sex-dependent patterns. In this review, we delve into the subject of sex bias in TLR activation and explore its clinical implications relatively to both the X chromosome and the hormonal environment. The overarching objective is to enhance our understanding of the fundamental mechanisms underlying these sex differences.

Older females have increased mortality after trauma as compared with younger females and males, associated with increased fibrinolysis

INTRODUCTION

Female sex may provide a survival benefit after trauma, possibly attributable to protective effects of estrogen. This study aimed to compare markers of coagulation between male and female trauma patients across different ages.

METHODS

Secondary analysis of a prospective cohort study that was conducted at six trauma centers. Trauma patients presenting with full trauma team activation were eligible for inclusion. Patients with a penetrating trauma or traumatic brain injury were excluded. Upon hospital arrival, blood was drawn for measurement of endothelial and coagulation markers and for rotational thromboelastometry measurement. Trauma patients were divided into four categories: males younger than 45 years, males 45 years or older, females younger than 45 years, and females 45 years or older. In a sensitivity analysis, patients between 45 and 55 years old were excluded to control for menopausal transitioning. Groups were compared with a Kruskal-Wallis test with Bonferroni correction. A logistic regression was performed to assess whether the independent effect of sex and age on mortality.

RESULTS

A total of 1,345 patients were available for analysis. Compared with the other groups, mortality was highest in females 45 years or older, albeit not independent from injury severity and shock. In the group of females 45 years or older, there was increased fibrinolysis, demonstrated by increased levels of plasmin-antiplasmin complexes with a concomitant decrease in α2-antiplasmin. Also, a modest decrease in coagulation factors II and X was observed. Fibrinogen levels were comparable between groups. The sensitivity analysis in 1,104 patients demonstrated an independent relationship between female sex, age 55 years or older, and mortality. Rotational thromboelastometry profiles did not reflect the changes in coagulation tests.

CONCLUSION

Female trauma patients past their reproductive age have an increased risk of mortality compared with younger females and males, associated with augmented fibrinolysis and clotting factor consumption. Rotational thromboelastometry parameters did not reflect coagulation differences between groups.

LEVEL OF EVIDENCE

Prognostic and Epidemiological; Level III.

Sex dimorphisms in coagulation: Implications in trauma-induced coagulopathy and trauma resuscitation

Trauma-induced coagulopathy (TIC) is one of the leading causes of preventable death in injured patients. Consequently, it is imperative to understand the mechanisms underlying TIC and how to mitigate this mortality. An opportunity for advancement stems from the awareness that coagulation demonstrates a strong sex-dependent effect. Females exhibit a relative hypercoagulability compared to males, which persists after injury and confers improved outcomes. The mechanisms underlying sex dimorphisms in coagulation and its protective effect after injury have yet to be elucidated. This review explores sex dimorphisms in enzymatic hemostasis, fibrinogen, platelets, and fibrinolysis, with implications for resuscitation of patients with TIC.

Parameters influencing health-related quality of life after severe trauma: a systematic review (part II)

INTRODUCTION

It is increasingly recognized that health-related quality of life (HRQoL) is a relevant outcome to study in populations comprising severely injured patients. Although some studies have readily demonstrated a compromised HRQoL in those patients, evidence regarding factors that predict HRQoL is scarce. This hinders attempts to prepare patient-specific plans that may aid in revalidation and improved life satisfaction. In this review, we present identified predictors of HRQoL in patients that have suffered severe trauma.

METHODS

The search strategy included a database search until the 1st of January 2022 in the Cochrane Library, EMBASE, PubMed, and Web of Science, and reference checking. Studies were eligible for inclusion when (HR)QoL was studied in patients with major, multiple, or severe injury and/or polytrauma, as defined by authors by means of an Injury Severity Score (ISS) cut-off value. The results will be discussed in a narrative manner.

RESULTS

A total of 1583 articles were reviewed. Of those, 90 were included and used for analysis. In total, 23 possible predictors were identified. The following parameters predicted reduced HRQoL in severely injured patients and came forward in at least more than three studies: higher age, female gender, lower extremity injuries, higher rate of injury severity, lower achieved educational level, presence of (pre-existing) comorbidities and mental illness, longer duration of hospital stay, and high level of disability.

CONCLUSION

Age, gender, injured body region, and severity of injury were found to be good predictors of health-related quality of life in severely injured patients. A patient-centered approach, based on individual, demographic, and disease-specific predictors, is highly recommended.

Twenty-year United States national, demographic and regional mortality trends from traumatic thoracic aortic injury, 1999 to 2019

INTRODUCTION

Traumatic Thoracic Aortic Injury (TTAI) is associated with high mortality rates and is the second leading cause of death in traumatic patients. There has been a considerable advancement in the management of TTAI with novel and improved surgical procedures and imaging modalities. The aim of this study was to determine the national demographic and regional trends in mortality associated with TTAI in the United States across twenty years, 1999 to 2019.

METHODS

The multiple cause of death data on Centers for Disease Control and Prevention Wide-Ranging Online Data for Epidemiologic Research (CDC-WONDER) database was utilized to query death certificates for TTAI from 1999 to 2019, in the United States. The International Classification of the Diseases, Tenth Revision (ICD-10) code S25.0 was used to identify and abstract data for TTAI related deaths. The data was further abstracted based on age, race, gender and Census-Bureau defined regions. The age-adjusted mortality rate (AAMR) per 100,000 population-year and Average Annual Percentage Change (AAPC) with 95 % Confidence Interval were computed. The JoinPoint software was utilized to compute the temporal trends in mortality based on a segmented change and AAPC calculation.

RESULTS

A total of 20,842 TTAI associated deaths occurred from 1999 to 2019 corresponding to an AAMR of 0.407(0.401-0.412) per 100,000 population-year. The overall AAMR reduced from 0.759 to 0.223 per 100,000 population-year from 1999 to 2019[average APC -6.5(-7.5; -5.5)]. The reduction was reported in both <45 age group [average APC -6.5(-7.9; -5.1)] and >45 age group [-6.2(-7.3; -5.0)]; among females [average APC -6.1(-7.8; -4.3)] and males [-6.1(-7.2; -5.0)]; among Whites [average APC -6.9(-7.8; -5.9)] and Blacks [-5.0(-7.4; -2.5)]. The reduction in mortality as per the census region was highest in the west followed by Mid-West, North-East and South [average APC -6.8(-8.6; -5.0); -6.2(-8.8; -3.6); -5.7(-7.0; -4.4); -5.5(-7.4; -3.6), respectively].

CONCLUSION

There was a significant decrease in the TTAI associated mortality trends in the United States across 1999-2019 with a consistent decline in all demographic and regional subgroups.

Long-term survival after major trauma: a retrospective nationwide cohort study from the National Health Insurance Research Database

BACKGROUND

Most trauma-related studies are focused on short-term survival and complications within the index admission, and the long-term outcomes beyond discharge are mainly unknown. The purpose of this study was to analyze the data from the National Health Insurance Research Database (NHIRD) and to assess the long-term survival of major trauma patients after being discharged from the index admission.

MATERIAL AND METHODS

This retrospective, observational study included all patients with major trauma (injury severity score ≥16) in Taiwan from 2003 to 2007, and a 10-year follow-up was conducted on this cohort. Patients aged 18-70 who survived the index admission were enrolled. Patients who survived less than one year after discharge (short survival, SS) and those who survived for more than one year (long survival, LS) were compared. Variables, including preexisting factors, injury types, and short-term outcomes and complications, were analyzed, and the 10-year Kaplan-Meier survival analysis was conducted.

RESULTS

In our study, 9896 patients were included, with 2736 in the SS group and 7160 in the LS group. Age, sex, comorbidities, low income, cardiopulmonary resuscitation event, prolonged mechanical ventilation, prolonged ICU length of stay (LOS), and prolonged hospital LOS were identified as the independent risk factors of SS. The 10-year cumulative survival for major trauma patients was 63.71%, and the most mortality (27.64%) occurred within the first year after discharge.

CONCLUSION

27.64% of patients would die one year after being discharged from major trauma. Major trauma patients who survived the index admission still had significantly worse long-term survival than the general population, but the curve flattened and resembled the general population after one year.

A COMPARATIVE ANALYSIS TO DETERMINE THE OPTIMUM HISTONE DEACETYLASE INHIBITORS AND ADMINISTRATION ROUTE FOR IMPROVING SURVIVAL AND ORGAN INJURY IN RATS AFTER HEMORRHAGIC SHOCK

ABSTRACT

Objective: Histone deacetylase inhibitors (HDACIs) have been reported to improve survival in rats with hemorrhagic shock (HS). However, no consensus exists on the most effective HDACIs and their administration routes. We herein aimed to determine the optimal HDACIs and administration route in rats with HS. Methods: Survival analysis: In experiment I, male Sprague-Dawley rats were subjected to HS (mean arterial pressure [MAP] was maintained at 30-40 mm Hg for 20 min), and intravenously injected with the following agents (n = 8 per group): (1) no treatment, (2) vehicle (VEH), (3) entinostat (MS-275), (4) [ N -((6-(Hydroxyamino)-6-oxohexyl)oxy)-3,5-dimethylbenzamide] (LMK-235), (5) tubastatin A, (6) trichostatin A (TSA), and (7) sirtinol. In experiment II, rats were intraperitoneally injected with TSA. Mechanism research: In experiments I and II, rats were observed for 3 h, after which blood samples and liver, heart, and lung tissues were harvested. Results: In experiment I, 75% rats in the VEH group but only 25% rats in the LMK-235 and sirtinol groups died within ≤5 h of treatment, whereas the survival of rats in the MS-275, tubastatin A, and TSA groups was significantly prolonged. MS-275, LMK-235, tubastatin A, and TSA significantly reduced histopathological scores, apoptosis cell numbers, and inflammatory cytokine levels. In experiment II, the survival was longer after i.v. TSA treatment than after i.p. TSA treatment, and the IL-6 levels in the heart were significantly lower in rat who received i.p. TSA treatment than in those who received i.v. TSA treatment. Conclusions: The i.v. effect was superior to the i.p. effect, while nonselective and isoform-specific classes I and IIb HDACIs had similar effects.

Sex Dimorphism in Outcome of Trauma Patients Presenting with Severe Shock: A Multicenter Cohort Study

Background: The objective of this study was to determine the association between sex and outcome among severely injured patients who were admitted in severe shock. Methods: A retrospective multicenter study was performed in trauma patients (Injury Severity Score (ISS) ≥ 16) aged ≥ 16 presenting with severe shock (Shock Index > 1.3) over a 4-year period. To determine if sex was associated with mortality, Intensive Care Unit (ICU) admission, mechanical ventilation, blood transfusion and in-hospital complications, multivariable logistic regressions were performed. Results: In total, 189 patients were admitted to the Emergency Department in severe shock. Multivariable logistic regression analysis showed that female sex was independently associated with a decreased likelihood of acute kidney injury (OR 0.184; 95% CI 0.041-0.823; p = 0.041) compared to the male sex. A significant association between female sex and mortality, ICU admission, mechanical ventilation, other complications and packed red blood cells transfusion after admission could not be confirmed. Conclusion: Female trauma patients in severe shock were significantly less likely to develop AKI during hospital stay. These results could suggest that female trauma patients may manifest a better-preserved physiologic response to severe shock when compared to their male counterparts. Prospective studies with a larger study population are warranted.

Platelet and cryoprecipitate transfusions from female donors improve coagulopathy in vitro

BACKGROUND

Females are relatively hypercoagulable compared with males, with increased platelet aggregation and improved clot dynamics. However, sex differences in coagulation have not yet been considered in transfusion guidelines. Therefore, our objective was to evaluate hemostatic differences in sex concordant and sex discordant cryoprecipitate and platelet transfusions. We hypothesized that transfusion of blood products from female donors results in improved coagulopathy compared with male blood products.

METHODS

This was a cohort study evaluating sex dimorphisms in coagulation assays and clotting factors in healthy volunteer plasma and cryoprecipitate. Sex dimorphisms in transfusions were evaluated using an in vitro coagulopathy model. Female or male platelets or single-donor cryoprecipitate was added to "recipient" whole blood after dilution of recipient blood with citrated saline to provoke a coagulopathic profile. Citrated native thromboelastography was then performed. Liquid chromatography/mass spectroscopy was performed on single-donor cryoprecipitate to evaluate sex dimorphisms in the proteome of cryoprecipitate.

RESULTS

Females have an increased proportion of functional fibrinogen. Transfusion of female-donor platelets and cryoprecipitate induces a larger decrease in R time and greater increase in angle than male-donor platelets or cryoprecipitate. Female-donor cryoprecipitate has increased factor V and factor XIII compared with male cryoprecipitate, and comprehensive proteomics revealed sex differences in several proteins with potential immunological significance.

CONCLUSION

Platelets and cryoprecipitate from female donors improve coagulopathy more than male blood products in vitro. Increased factor V and factor XIII activity as well as increased fibrinogen activity in female donors appears to drive this disparity. Sex differences in the proteome of cryoprecipitate may influence how transfusions modulate the thromboinflammation of trauma. The differing hemostatic profiles of female and male blood products suggest the potential role of sex-specific transfusions guidelines in hemostatic resuscitation.

Effects of hemodilution on coagulation function during prolonged hypotensive resuscitation in a porcine model of severe hemorrhagic shock

Background

Although hemorrhage remains the leading cause of survivable death in casualties, modern conflicts are becoming more austere limiting available resources to include resuscitation products. With limited resources also comes prolonged evacuation time, leaving suboptimal prehospital field care conditions. When blood products are limited or unavailable, crystalloid becomes the resuscitation fluid of choice. However, there is concern of continuous crystalloid infusion during a prolonged period to achieve hemodynamic stability for a patient. This study evaluates the effect of hemodilution from a 6-hour prehospital hypotensive phase on coagulation in a porcine model of severe hemorrhagic shock.

Methods

Adult male swine (n=5/group) were randomized into three experimental groups. Non-shock (NS)/normotensive did not undergo injury and were controls. NS/permissive hypotensive (PH) was bled to the PH target of systolic blood pressure (SBP) 85±5 mm Hg for 6 hours of prolonged field care (PFC) with SBP maintained via crystalloid, then recovered. Experimental group underwent controlled hemorrhage to mean arterial pressure 30 mm Hg until decompensation (Decomp/PH), followed by PH resuscitation with crystalloid for 6 hours. Hemorrhaged animals were then resuscitated with whole blood and recovered. Blood samples were collected at certain time points for analysis of complete blood counts, coagulation function, and inflammation.

Results

Throughout the 6-hour PFC, hematocrit, hemoglobin, and platelets showed significant decreases over time in the Decomp/PH group, indicating hemodilution, compared with the other groups. However, this was corrected with whole blood resuscitation. Despite the appearance of hemodilution, coagulation and perfusion parameters were not severely compromised.

Conclusions

Although significant hemodilution occurred, there was minimal impact on coagulation and endothelial function. This suggests that it is possible to maintain the SBP target to preserve perfusion of vital organs at a hemodilution threshold in resource-constrained environments. Future studies should address therapeutics that can mitigate potential hemodilutional effects such as lack of fibrinogen or platelets.

Level of evidence

Not applicable-Basic Animal Research.

The effects of sex and neuter status on trauma survival in dogs: A Veterinary Committee on Trauma registry study

OBJECTIVE

To determine the effect of sex and neuter status on trauma survival in dogs.

DESIGN

Multi-institutional prospective case series, September 2013 to March 2019, retrospectively analyzed.

SETTING

Level I and II Veterinary Trauma Centers.

ANIMALS

Consecutive sample of 2649 dogs in the American College of Veterinary Emergency and Critical Care Veterinary Committee on Trauma patient registry meeting inclusion criteria. For inclusion, dogs had to have complete data entries, be postpubertal (≥7 months age in females and ≥10 months age in males), and have sustained moderate to severe trauma (animal trauma triage [ATT] score ≥5/18). Dogs that were dead upon arrival, euthanized for financial or unknown reasons alone, or that were presented by a Good Samaritan but subsequently humanely euthanized were excluded.

MEASUREMENTS AND MAIN RESULTS

Data collected included age, sex, neuter status (intact, neutered), trauma type (blunt, penetrating, both), outcome (survived to hospital discharge, died, euthanized), and reason for euthanasia (grave prognosis, financial reasons, or both). Of 2649 eligible dogs, 56% survived to hospital discharge (n = 1469). Neutered females had a significantly higher survival rate (58.3% vs 51.3%; P = 0.03) compared to intact females, and neutered males had a significantly higher survival rate (56.6% vs 50.7%; P = 0.04) compared to intact males. There was no significant difference in survival between intact females and intact males (P = 0.87) or between neutered females and neutered males (P = 0.46). Mean cumulative ATT score was higher in intact groups and was found to be a significant predictor of survival (P < 0.01). Based on logistic models, overall odds of survival were 20.7% greater in neutered dogs.

CONCLUSIONS

Gonadectomy is associated with lower ATT scores and improved survival after moderate to severe trauma in both female and male dogs.

Cerebral Regional Tissue Oxygenation as Surrogate for Blood Loss in Nonhuman Primate Models of Shock

INTRODUCTION

Hemorrhage is the leading cause of preventable death, with a majority of mortalities in the prehospital setting. Current hemorrhage resuscitation guidelines cannot predict the critical point of intervention to activate massive transfusion (MT) and prevent cardiovascular decompensation. We hypothesized that cerebral regional tissue oxygenation (CrSO₂) would indicate MT need in nonhuman primate models of hemorrhagic shock.

METHODS

Nineteen anesthetized male rhesus macaques underwent hemorrhage via a volume-targeted (VT) or pressure-targeted (PT) method. VT animals were monitored for 30 min following 30% blood volume hemorrhage. PT animals were hemorrhaged to mean arterial pressure (MAP) of 20 mmHg and maintained for at least 60 min until decompensation. Statistics for MAP, heart rate (HR), end tidal carbon dioxide (EtCO₂), and CrSO₂ were analyzed via one- or two-way repeated-measures analysis of variance, Pearson's R, and receiver-operator curve. A P < 0.05 is considered significant.

RESULTS

Following initial hemorrhage (S0), there were no significant differences between groups. After cessation of hemorrhage in the VT group, MAP and EtCO₂ returned to baseline while CrSO₂ plateaued. The PT group maintained model-defined low MAP, suppressing EtCO₂, and significantly decreased CrSO₂ compared to the VT group by S25. Linear regression of CrSO₂versus shed blood volume demonstrated R² = 0.7539. CrSO₂ of 47% was able to detect >40% blood loss with an area under the curve of 0.9834 at 92.3% (66.7%-99.6%) sensitivity and 95.5% (84.9%-99.2%) specificity.

CONCLUSIONS

Regardless of hemorrhage modality and compensatory response, CrSO₂ correlated strongly with shed blood volume. Analysis demonstrated that CrSO₂ values below 49% indicate Advanced Trauma Life Support class IV shock (blood loss>40%). CrSO₂ at the point of care may help indicate MT need earlier and more accurately than traditional markers.

The Clinical Impact of Platelets on Post-Injury Serum Creatinine Concentration in Multiple Trauma Patients: A Retrospective Cohort Study

Background and objective: Platelets contribute to the immunological response after multiple trauma. To determine the clinical impact, this study analyzes the association between platelets and creatinine concentration as an indicator of kidney function in polytraumatized patients. Methods: We investigated all patients presenting an Injury Severity Score (ISS) ≥16 for a 2-year period at our trauma center. Platelet counts and creatinine concentrations were analyzed, and correlation analysis was performed within 10 days after multiple trauma. Results: 83 patients with a median ISS of 22 were included. Platelet count was decreased on day 3 (p ≤ 0.001) and increased on day 10 (p ≤ 0.001). Platelet count was elevated on day 10 in younger patients and diminished in severely injured patients (ISS ≥35) on day 1 (p = 0.012) and day 3 (p = 0.011). Creatinine concentration was decreased on day 1 (p = 0.003) and day 10 (p ≤ 0.001) in female patients. Age (p = 0.01), male sex (p = 0.004), and injury severity (p = 0.014) were identified as factors for increased creatinine concentration on day 1, whereas platelets (p = 0.046) were associated with decreased creatinine concentrations on day 5 after multiple trauma. Conclusions: Kinetics of platelet count and creatinine concentration are influenced by age, gender, and trauma severity. There was no clear correlation between platelet counts and creatinine concentration. However, platelets seem to have a modulating effect on creatinine concentrations in the vulnerable phase after trauma.

The Association between Skull Bone Fractures and the Mortality Outcomes of Patients with Traumatic Brain Injury

Introduction

Skull fractures are often found in patients with traumatic brain injury (TBI). Although skull fractures may indicate greater force impact and are associated with local or diffuse brain injuries, the prognostic value of skull fractures remains unclear. This retrospective study aimed to assess the association between skull fractures and mortality in patients with TBI.

Methods

This study included 5,430 TBI patients registered in the trauma registry system from January 2009 to December 2018. Clinical and demographic data including age, sex, trauma mechanisms, comorbidities, Glasgow Coma Scale (GCS) score, abbreviated injury score (AIS)-head, injury severity score (ISS), and in-hospital mortality were acquired. Multiple logistic regression and propensity score matching were used to elucidate the effect of skull fractures on mortality outcomes of TBI patients.

Results

Compared to TBI patients without skull fracture, patients with skull fractures were predominantly male, younger, had lower GCS upon arrival at the emergency room, and had higher AIS-head, ISS, and in-hospital mortality. The patients with skull fracture had 1.7-fold adjusted odds of mortality (95% confidence interval (CI): 1.27–2.25; p < 0.001) than those without skull fracture, controlling for age, sex, comorbidities, and AIS-head. Additionally, the propensity score-matched analysis of 1,023 selected paired patients revealed that skull fracture was significantly associated with increased 1.4-fold odds of risk for mortality (95% CI: 1.02–1.88; p=0.036).

Conclusions

Using a propensity score-matched cohort to attenuate the confounding effect of age, comorbidities, and injury severity, skull fracture was identified as a significant independent risk factor for mortality in patients with TBI.

Thromboelastography-Based Evaluation of Gender-Associated Hypercoagulability

BACKGROUND

Age, race, and gender differences in coagulation status of healthy volunteers have been reported in previous case series; however, rigorous multivariate analysis adjusting for these factors is lacking. We aimed to investigate the effects of age, race, and gender on baseline coagulation status in healthy volunteers.

METHODS

Thirty healthy volunteer controls with no history of bleeding or thrombotic events and no previous anticoagulant or antiplatelet use were recruited. Citrated and heparinized blood samples were drawn, and kaolin and platelet-mapping thromboelastography (TEG) assays performed.

RESULTS

Thirty participants had a mean age of 37, mean body mass index of 29 kg/m², and were 47% African-American and 70% female. Women were significantly older than men (40 ± 11 y vs 28 ± 7 y, P = .002); there were no significant differences in demographics by race. Multivariate analysis of variance for the effect of age, race, and gender across TEG parameters yielded evidence for gender differences in hypercoagulability (Pillai's trace P = .02), which appear to be driven by differences in K-time, alpha angle, maximal amplitude, and G parameter. Women were hypercoagulable compared to men, as manifested by shorter K-time, steeper alpha angle, higher maximal amplitude, and larger G parameter.

DISCUSSION

Women at baseline have relatively hypercoagulable fibrin deposition kinetics, platelet contributions to clot formation, and overall clot strength compared to men, even when adjusted for age and race. Additional research is needed to specifically detail the key patient-level factors, clinical implications, and opportunities for tailored therapy related to gender-associated hypercoagulability.

State-of-the-Art Review: Sex Hormone Therapy in Trauma-Hemorrhage

ABSTRACT

Trauma-hemorrhage is the leading cause of prehospital and early in-hospital deaths, while also significantly contributing to the later development of multisystem organ dysfunction/failure and sepsis. Common and advanced resuscitative methods would potentially demonstrate benefits in the prehospital setting; however, they face a variety of barriers to application and implementation. Thus, a dialogue around a novel adjunct has arisen, sex hormone therapy. Proposed candidates include estradiol and its derivatives, metoclopramide hydrochloride/prolactin, dehydroepiandrosterone, and flutamide; with each having demonstrated a range of salutary effects in several animal model studies. Several retrospective analyses have observed a gender-based dimorphism in mortality following trauma-hemorrhage, thus suggesting that estrogens contribute to this pattern. Trauma-hemorrhage animal models have shown estrogens offer protective effects to the cardiovascular, pulmonary, hepatic, gastrointestinal, and immune systems. Additionally, a series of survival studies utilizing 17α-ethinylestradiol-3-sulfate, a potent, water-soluble synthetic estrogen, have demonstrated a significant survival benefit and beneficial effects on cardiovascular function. This review presents the findings of retrospective clinical studies, preclinical animal studies, and discusses how and why 17α-ethinylestradiol-3-sulfate should be considered for investigation within a prospective clinical trial.

An estrogen (17α-ethinyl estradiol-3-sulfate) reduces mortality in a swine model of multiple injuries and hemorrhagic shock

BACKGROUND

Although 17α-ethinyl estradiol-3-sulfate (EES) reduces mortality in animal models of controlled hemorrhage, its role in a clinically relevant injury model is unknown. We assessed the impact of EES in a swine model of multiple injuries and hemorrhage.

METHODS

The study was performed under Good Laboratory Practice, with 30 male uncastrated swine (25-50 kg) subjected to tibial fracture, pulmonary contusion, and 30% controlled hemorrhage for an hour. Animals were randomized to one of five EES doses: 0 (control), 0.3, 1, 3, and 5 mg/kg, administered postinjury. Subjects received no resuscitation and were observed for 6 hours or until death. Survival data were analyzed using Cox-proportional hazard regression. Left ventricular pressure-volume loops were used to derive preload recruitable stroke work as a measure of cardiac inotropy. Immediate postinjury preload recruitable stroke work values were compared with values at 1 hour post-drug administration.

RESULTS

Six-hour survival for the 0, 0.3, 1, 3, and 5 mg/kg groups was 0%, 50%, 33.3%, 16.7%, and 0%, respectively. Following Cox regression, the hazard (95% confidence interval) of death was significantly reduced in the 0.3 (0.22 [0.05-0.93]) and 1 (0.24 [0.06-0.89]) mg/kg groups but not the 3 (0.49 [0.15-1.64]) and 5 (0.46 [0.14-1.47]) mg/kg groups. Mean survival time was significantly extended in the 1 mg/kg group (246 minutes) versus the 0 mg/kg group (96 minutes) (p = 0.04, t test). At 1 hour post-drug administration, inotropy was significantly higher than postinjury values in the 0.3 and 1 mg/kg groups (p = 0.003 and p < 0.001, respectively). Inotropy was unchanged in the 3 and 5 mg/kg groups but significantly depressed in the control (p = 0.022).

CONCLUSION

Administration of EES even in the absence of fluid resuscitation reduces mortality and improves cardiac inotropy in a clinically relevant swine model of multiple injuries and hemorrhage. These findings support the need for a clinical trial in human trauma patients.

Therapeutically Targeting Microvascular Leakage in Experimental Hemorrhagic SHOCK: A Systematic Review and Meta-Analysis

BACKGROUND

Microvascular leakage is proposed as main contributor to disturbed microcirculatory perfusion following hemorrhagic shock and fluid resuscitation, leading to organ dysfunction and unfavorable outcome. Currently, no drugs are available to reduce or prevent microvascular leakage in clinical practice. We therefore aimed to provide an overview of therapeutic agents targeting microvascular leakage following experimental hemorrhagic shock and fluid resuscitation.

METHODS

PubMed, EMBASE.com, and Cochrane Library were searched in January 2021 for preclinical studies of hemorrhagic shock using any therapeutic agent on top of standard fluid resuscitation. Primary outcome was vascular leakage, defined as edema, macromolecule extravasation, or glycocalyx degradation. Drugs were classified by targeting pathways and subgroup analyses were performed per organ.

RESULTS

Forty-five studies, published between 1973 and 2020, fulfilled eligibility criteria. The included studies tested 54 different therapeutics mainly in pulmonary and intestinal vascular beds. Most studies induced trauma besides hemorrhagic shock. Forty-four therapeutics (81%) were found effective to reduce microvascular leakage, edema formation, or glycocalyx degradation in at least one organ. Targeting oxidative stress and apoptosis was the predominantly effective strategy (SMD: -2.18, CI [-3.21, -1.16], P < 0.0001). Vasoactive agents were found noneffective in reducing microvascular leakage (SMD: -0.86, CI [-3.07, 1.36], P = 0.45).

CONCLUSION

Pharmacological modulation of pathways involved in cell metabolism, inflammation, endothelial barrier regulation, sex hormones and especially oxidative stress and apoptosis were effective in reducing microvascular leakage in experimental hemorrhagic shock with fluid resuscitation. Future studies should investigate whether targeting these pathways can restore microcirculatory perfusion and reduce organ injury following hemorrhagic shock.

SYSTEMATIC REVIEW REGISTRATION NUMBER

CRD42018095432.

Trauma-induced coagulopathy

Uncontrolled haemorrhage is a major preventable cause of death in patients with traumatic injury. Trauma-induced coagulopathy (TIC) describes abnormal coagulation processes that are attributable to trauma. In the early hours of TIC development, hypocoagulability is typically present, resulting in bleeding, whereas later TIC is characterized by a hypercoagulable state associated with venous thromboembolism and multiple organ failure. Several pathophysiological mechanisms underlie TIC; tissue injury and shock synergistically provoke endothelial, immune system, platelet and clotting activation, which are accentuated by the 'lethal triad' (coagulopathy, hypothermia and acidosis). Traumatic brain injury also has a distinct role in TIC. Haemostatic abnormalities include fibrinogen depletion, inadequate thrombin generation, impaired platelet function and dysregulated fibrinolysis. Laboratory diagnosis is based on coagulation abnormalities detected by conventional or viscoelastic haemostatic assays; however, it does not always match the clinical condition. Management priorities are stopping blood loss and reversing shock by restoring circulating blood volume, to prevent or reduce the risk of worsening TIC. Various blood products can be used in resuscitation; however, there is no international agreement on the optimal composition of transfusion components. Tranexamic acid is used in pre-hospital settings selectively in the USA and more widely in Europe and other locations. Survivors of TIC experience high rates of morbidity, which affects short-term and long-term quality of life and functional outcome.

Valproic acid treatment rescues injured tissues after traumatic brain injury

BACKGROUND

No agents that are specifically neuroprotective are currently approved to emergently treat patients with traumatic brain injury (TBI). The histone deacetylase inhibitor, high-dose valproic acid (VPA) has been shown to have cytoprotective potential in models of combined TBI and hemorrhagic shock, but it has not been tested in an isolated TBI model. We hypothesized that VPA, administered after isolated TBI, will penetrate the injured brain, attenuate the lesion size, and activate prosurvival pathways.

METHODS

Yorkshire swine were subjected to severe TBI by cortical impact. One hour later, animals were randomized to VPA treatment (150 mg/kg delivered intravenously for 1 hour; n = 4) or control (saline vehicle; n = 4) groups. Seven hours after injury, animals were sacrificed, and brain lesion size was measured. Mass spectrometry imaging was used to visualize and quantitate brain tissue distribution of VPA. Sequential serum samples were assayed for key biomarkers and subjected to proteomic and pathway analysis.

RESULTS

Brain lesion size was 50% smaller (p = 0.01) in the VPA-treated animals (3,837 ± 948 mm) compared with the controls (1,900 ± 614 mm). Endothelial regions had eightfold higher VPA concentrations than perivascular regions by mass spectrometry imaging, and it readily penetrated the injured brain tissues. Serum glial fibrillary acid protein was significantly lower in the VPA-treated compared with the control animals (p < 0.05). More than 500 proteins were differentially expressed in the brain, and pathway analysis revealed that VPA affected critical modulators of TBI response including calcium signaling pathways, mitochondria metabolism, and biosynthetic machinery.

CONCLUSION

Valproic acid penetrates injured brain tissues and exerts neuroprotective and prosurvival effects that resulted in a significant reduction in brain lesion size after isolated TBI. Levels of serum biomarkers reflect these changes, which could be useful for monitoring the response of TBI patients during clinical studies.

Early outcomes following trauma related to sex: A matched analysis of military service members in the department of defense trauma registry

BACKGROUND

Several studies have identified sex as a factor influencing early outcomes after trauma. With the increased representation of women in combat roles, there is a need for improved understanding of the pathophysiology of traumatic injury in women. The purpose of this study was to define sex-based differences in early combat trauma outcomes amongst military service members.

METHODS

A retrospective review of the Department of Defense Trauma Registry between 2008 and 2016 was performed. A 2:1 case control match was performed to match for Injury Severity Score, mechanism of injury, and age. The primary outcome of the study was mortality.

RESULTS

A total of 4,625 patients were included in the study, 2.2% of whom were women. Women were less significantly injured than men (Injury Severity Score, 7.7 vs. 11, p = 0.003) and more likely to sustain blunt trauma (81% vs. 62.5%, p = 0.01). After case-control matching, 202 men and 101 women were evaluated. There was no statistical difference in the primary outcome of mortality. There was no statistical difference in Glasgow Coma Scale score, crystalloid or colloid administration, Packed Red Blood Cells (PRBC), platelet, cryoprecipitate, or plasma usage between men and women.

CONCLUSION

Contrary to the civilian trauma literature, our study demonstrated no significant difference in early mortality between male and female combat casualties in a matched cohort. This finding may represent a difference in injury patterns, resuscitation practices, or lifesaving interventions in a deployed setting as compared with civilian setting. As the proportion of women involved in combat operations continues to increase, prospective studies should be performed to better define injury patterns, as well as early and late outcomes related to military trauma in the female population.

LEVEL OF EVIDENCE

Retrospective, Level IV.

The chest wall gender divide: females have better cardiopulmonary function and exercise tolerance despite worse deformity in pectus excavatum

PURPOSE

Pectus excavatum (PE) is a chest wall deformity of variable severity and symptomatology. Existing female-specific literature highlights breast asymmetry and cosmetic reconstruction. We sought to evaluate gender differences in cardiopulmonary function.

METHODS

Cardiac MRIs, pulmonary function tests (PFTs), and cardiopulmonary exercise tests (CPETs) were reviewed in 345 patients undergoing preoperative evaluation for PE. Regression modeling was used to evaluate associations between gender and clinical endpoints of cardiopulmonary function.

RESULTS

Mean age was 15.2 years, 19% were female, 98% were white. Pectus indices included median Haller Index (HI) of 4.8, mean depression index (DI) of 0.63, correction index (CI) of 33.6%, and Cardiac Compression Index (CCI) of 2.79. Cardiac assessment revealed decreased right and left ventricular ejection fraction (RVEF, LVEF) in 16% and 22% of patients, respectively. PFTs and CPETs were abnormal in ~ 30% of patients. While females had deeper PE deformities-represented by higher pectus indices-they had superior function with higher RVEF, LVEF Z-scores, FEV₁, VO₂ max, O₂ pulse, work, and breathing reserve (p < 0.05).

CONCLUSION

Despite worse PE deformity and symptomatology, females had a better cardiopulmonary function and exercise tolerance than males. Further research is needed to assess the precise mechanisms of this phenomenon and postoperative outcomes in this population.

Neuroendocrine Modulation of the Immune Response after Trauma and Sepsis: Does It Influence Outcome?

Although the treatment of multiple-injured patients has been improved during the last decades, sepsis and multiple organ failure (MOF) still remain the major cause of death. Following trauma, profound alterations of a large number of physiological systems can be observed that may potentially contribute to the development of sepsis and MOF. This includes alterations of the neuroendocrine and the immune system. A large number of studies focused on posttraumatic changes of the immune system, but the cause of posttraumatic immune disturbance remains to be established. However, an increasing number of data indicate that the bidirectional interaction between the neuroendocrine and the immune system may be an important mechanism involved in the development of sepsis and MOF. The aim of this article is to highlight the current knowledge of the neuroendocrine modulation of the immune system during trauma and sepsis.

Factors Associated With Long-term Outcomes After Injury: Results of the Functional Outcomes and Recovery After Trauma Emergencies (FORTE) Multicenter Cohort Study

OBJECTIVE

The aim of this study was to determine factors associated with patient-reported outcomes, 6 to 12 months after moderate to severe injury.

SUMMARY OF BACKGROUND DATA

Due to limitations of trauma registries, we have an incomplete understanding of factors that impact long-term patient-reported outcomes after injury. As 96% of patients survive their injuries, several entities including the National Academies of Science, Engineering and Medicine have called for a mechanism to routinely follow trauma patients and determine factors associated with survival, patient-reported outcomes, and reintegration into society after trauma.

METHODS

Over 30 months, major trauma patients [Injury Severity Score (ISS) ≥9] admitted to 3 Level-I trauma centers in Boston were assessed via telephone between 6 and 12 months after injury. Outcome measures evaluated long-term functional, physical, and mental-health outcomes. Multiple regression models were utilized to identify patient and injury factors associated with outcomes.

RESULTS

We successfully followed 1736 patients (65% of patients contacted). More than half (62%) reported current physical limitations, 37% needed help for at least 1 activity of daily living, 20% screened positive for posttraumatic stress disorder (PTSD), all SF-12 physical health subdomain scores were significantly below US norms, and 41% of patients who were working previously were unable to return to work. Age, sex, and education were associated with long-term outcomes, while almost none of the traditional measures of injury severity were.

CONCLUSION

The long-term sequelae of trauma are more significant than previously expected. Collection of postdischarge outcomes identified patient factors, such as female sex and low education, associated with worse recovery. This suggests that social support systems are potentially at the core of recovery rather than traditional measures of injury severity.

Impact of Hormonal Protection in Blunt and Penetrating Trauma: A Retrospective Analysis of the National Trauma Data Bank

Over the last decade, gender and age-related hormonal status of trauma patients have been increasingly recognized as outcome factors. In the present study, we examine a large cohort of trauma patients to better appraise the effects of gender and age on patient outcome after blunt and penetrating trauma. We hypothesize that adult females are at lower risk for complications and mortality relative to adult males after both blunt and penetrating trauma. A retrospective analysis was conducted of the National Trauma Data Bank examining hormonally active females for advantages in survival and outcome after blunt and/or penetrating trauma. Over 1.4 million incident trauma cases were identified between 2002 and 2006. Multiple logistic regressions were calculated for associations between gender and outcome, stratified by injury type, age, comorbidity, Injury Severity Score (ISS), and complications. Risk factors associated with mortality in our multiple logistic regression analyses included: penetrating trauma (odds ratio [OR, 2.31; 95% confidence interval [CI], 2.27 to 2.36); adult male (OR, 1.45; 95% CI, 1.41 to 1.49); and ISS 15 or greater (OR, 14.68; 95% CI, 14.38 to 14.98). Adult females demonstrated a survival advantage over adult males (OR, 0.69; 95% CI, 0.67 to 0.71). Adult females with ISS less than 15 demonstrated a distinct survival advantage compared with adult males after both blunt and penetrating trauma. These results warrant further investigation into the role of sex hormones in trauma.

Influence of alcohol consumption on blood coagulation in rotational thromboelastometry (ROTEM): an in-vivo study

Background

Twenty-five to 85% of trauma patients are under the influence of alcohol in addition to experiencing injury-related coagulation impairment. Viscoelastic point-of-care tests (thrombelastography [TEG], rotational thromboelastometry [ROTEM]) are popular tools for rapid hemostasis assessment and therapeutic decision-making in this and other settings. While alcohol affects these tests in-vitro, their specific effects in-vivo are unclear. Therefore, we evaluated the effects of alcohol ingestion on ROTEM parameters.

Methods

Twenty volunteers provided informed consent to drinking red wine, whisk(e)y, or vodka to a target blood alcohol concentration of 1‰ within one hour, calculated with the Widmark formula. Blood samples were collected before drinking, at a breath alcohol concentration of 0.5‰, and at 1.0‰, but no later than one hour. After each blood collection, ExTEM and FibTEM tests were performed directly "at the bedside."

Results

All participants had a blood alcohol concentration (BAC) of 0.00‰ at the beginning. The mean BACs at the second and third collection were 0.48 and 0.76‰, respectively. There were no significant differences in the ExTEM parameters. FibTEM measurements showed a significant difference at the A10 value (13.0 vs. 14.0 mm, P = 0.014) and a trend at the maximum amplitude (maximum clot firmness 13.7 vs. 16.2 mm, P = 0.075). We saw no significant differences in fibrinolysis parameters and no hyperfibrinolysis in our ROTEM measurements.

Conclusions

Ethanol ingestion can impair early fibrin polymerization. These results might be of special relevance in trauma and support routine application of ROTEM/TEG in such cases.

Evaluation of prolonged 'Permissive Hypotension': results from a 6-hour hemorrhage protocol in swine

Background

Tactical Combat Casualty Care guidelines for hemorrhage recommend resuscitation to systolic blood pressure (SBP) of 85±5 mm Hg during prehospital care. Success depends on transport to definitive care within the ‘golden hour’. As future conflicts may demand longer prehospital/transport times, we sought to determine safety of prolonged permissive hypotension (PH).

Methods

Adult male swine were randomized into three experimental groups. Non-shock (NS)/normotensive underwent anesthesia only. NS/PH was bled to SBP of 85±5 mm Hg for 6 hours of prolonged field care (PFC) with SBP maintained via crystalloid, then recovered. Experimental group underwent controlled hemorrhage to mean arterial pressure 30 mm Hg until decompensation (Decomp/PH), followed by 6 hours of PFC. Hemorrhaged animals were then resuscitated with whole blood and observed for 24 hours. Physiologic variables, blood, tissue samples, and neurologic scores were collected.

Results

Survival of all groups was 100%. Fluid volumes to maintain targeted SBP in PFC were significantly higher in the hemorrhage group than sham groups. After 24 hours’ recovery, no significant differences were observed in neurologic scores or cerebrospinal fluid markers of brain injury. No significant changes in organ function related to treatment were observed during PFC through recovery, as assessed by serum chemistry and histological analysis.

Conclusions

After 6 hours, a prolonged PH strategy showed no detrimental effect on survival or neurologic outcome despite the increased ischemic burden of hemorrhage. Significant fluid volume was required to maintain SBP—a potential logistic burden for prehospital care. Further work to define maximum allowable time of PH is needed.

Study type

Translational animal model.

Level of evidence

N/A.

Is there an association between female gender and outcome in severe trauma? A multi-center analysis in the Netherlands

INTRODUCTION

Little evidence suggest that female gender is associated with a lower risk of mortality in severely injured patients, especially in premenopausal women. Previous clinical studies have shown contradictory results regarding protective effects of gender on outcome after severe trauma. The objective of this study was to determine the association between gender and outcome (mortality and Intensive Care Unit (ICU) admission) among severely injured patients in the Netherlands.

METHODS

A retrospective multicentre study was performed including all polytrauma patients (Injury Severity Score (ISS) ≥16) admitted to the ED of three level 1 trauma centres, between January 1st, 2006 and December 31st, 2014. Data on age, gender, mechanism of injury, ISS, Abbreviated Injury Scale (AIS), prehospital intubation, Revised Trauma Score (RTS), systolic blood pressure (SBP) and Glasgow Coma Scale (GCS) upon admission at the Emergency Department was collected from three Regional Trauma Registries. To determine whether gender was an independent predictor of mortality and ICU admission, logistic regression analysis was performed.

RESULTS

Among 6865 trauma patients, male patients had a significantly higher ISS compared to female patients (26.3 ± 10.2 vs 25.3 ± 9.7, P = < 0.0001). Blunt trauma was significantly more common in the female group (95.2% vs 92.3%, P = < 0.0001). Males aged 16- to 44-years had a significant higher in-hospital mortality rate (10.4% vs 13.4%, P = 0.046). ICU admission rate was significantly lower in females (49.3% vs 54.5%, P = < 0.0001). In the overall group, logistic regression did not show gender as an independent predictor for in-hospital mortality (OR 1.020 (95% CI 0.865-1.204), P = 0.811) or mortality within 24 h (OR 1.049 (95% CI 0.829-1.327), P = 0.693). However, male gender was associated with an increased likelihood for ICU admission in the overall group (OR 1.205 (95% CI 1.046-1.388), P = 0.010).

CONCLUSION

The current study shows that in this population of severely injured patients, female sex is associated with a lower in-hospital mortality rate among those aged 16- to 44-years. Furthermore, female sex is independently associated with an overall decreased likelihood for ICU admission. More research is needed to examine the physiologic background of this protective effect of female sex in severe trauma.

Gender differences in trauma, shock and sepsis

Despite efforts in prevention and intensive care, trauma and subsequent sepsis are still associated with a high mortality rate. Traumatic injury remains the main cause of death in people younger than 45 years and is thus a source of immense social and economic burden. In recent years, the knowledge concerning gender medicine has continuously increased. A number of studies have reported gender dimorphism in terms of response to trauma, shock and sepsis. However, the advantageous outcome following trauma-hemorrhage in females is not due only to sex. Rather, it is due to the prevailing hormonal milieu of the victim. In this respect, various experimental and clinical studies have demonstrated beneficial effects of estrogen for the central nervous system, the cardiopulmonary system, the liver, the kidneys, the immune system, and for the overall survival of the host. Nonetheless, there remains a gap between the bench and the bedside. This is most likely because clinical studies have not accounted for the estrus cycle. This review attempts to provide an overview of the current level of knowledge and highlights the most important organ systems responding to trauma, shock and sepsis. There continues to be a need for clinical studies on the prevailing hormonal milieu following trauma, shock and sepsis.

Histone deacetylase inhibitors: Isoform selectivity improves survival in a hemorrhagic shock model

BACKGROUND

Hemorrhage is a leading preventable cause of death. Nonselective histone deacetylase inhibitors (HDACIs), such as valproic acid (VPA), have been shown to improve outcomes in hemorrhagic shock (HS). The HDACs can be divided into four functional classes (I, IIa/IIb, III, and IV). Classes I, IIa/IIb, and III have previously been implicated in the pathophysiology of HS. This study aimed to determine which HDAC class, or classes, are responsible for the survival benefit observed with nonselective HDACIs.

METHODS

Survival study: Sprague-Dawley rats were subjected to lethal HS (50% hemorrhage) and randomized to the following groups (n = 8): (1) no treatment, (2) normal saline vehicle, (3) cyclodextrin vehicle, (4) MS275 (class I HDACI), (5) VPA (class I/IIa HDACI), (6) MC1568 (class IIa HDACI), (7) ACY1083 (class IIb HDACI), and (8) EX527 (class III HDACI). Survival was monitored for 24 hours. Mechanistic study: Sprague-Dawley rats were subjected to sublethal HS (40% hemorrhage) and randomized to the same groups (n = 3), excluding EX527, based on results of the survival study. Tissues were harvested at 3 hours posttreatment, and expression of phosphorylated-AKT, β-catenin, acetylated histones H3 and H4, and acetylated α-tubulin were analyzed in myocardial tissue.

RESULTS

Survival rate was 12.5% in the untreated group, and did not improve with vehicle or MS275 treatment. EX527 improved survival to 50%, although this did not achieve statistical significance (p = 0.082). However, treatment with VPA, MC1568, and ACY1083 improved survival rates to 87.5%, 75%, and 75%, respectively (p < 0.05). The VPA-induced acetylation of both histones H3 and H4, while MC1568 and ACY1083 increased acetylation of histone H4. ACY1083 also induced acetylation of α-tubulin. All treatment groups, except MS275, increased phosphorylated-AKT, and β-catenin.

CONCLUSION

Inhibition of HDAC classes IIa or IIb, but not class I, activates prosurvival pathways, which may be responsible for the improved outcomes in rodent models of HS.

Predictors of Vasopressin Responsiveness in Critically Ill Adults

BACKGROUND

Vasopressin is commonly used as an adjunct vasopressor in shock. However, response to vasopressin varies among critically ill patients.

OBJECTIVE

To identify patient-specific factors that are associated with vasopressin responsiveness in critically ill adults.

METHODS

This retrospective, multicenter study included adult patients who were admitted to an intensive care unit (ICU) and received vasopressin for shock. Patients were excluded if they received vasopressin for less than 30 minutes, if vasopressin was initiated prior to ICU arrival, or if an additional vasopressor was initiated within 30 minutes of starting vasopressin. Responsiveness was defined as an increase in mean arterial pressure of ≥10 mm Hg or the ability to taper a concurrent catecholamine vasopressor. Patient-specific factors evaluated in a multivariate analysis included age, gender, ethnicity, body mass index, type of shock, serum pH, Sequential Organ Failure Assessment (SOFA) score, and use of stress-dose steroids. These variables were also evaluated in a subgroup analysis of patients with septic shock.

RESULTS

Of 1619 patients screened, 400 patients were included, with 231 identified as vasopressin responsive and 169 as nonresponsive. Vasopressin used as an adjunct vasopressor, as opposed to first line, during shock was the only variable associated with vasopressin responsiveness (odds ratio [OR] = 1.71; 95% CI = 1.10 to 2.65). Among the subgroup of patients with septic shock, female patients had a higher odds of responding than male patients (OR = 2.10; 95% CI = 1.12 to 3.95).

CONCLUSIONS

Vasopressin initiated as an adjunct vasopressor, as opposed to first-line therapy, was associated with response.

Sex-based differences in outcomes after severe injury: an analysis of blunt trauma patients in China

BACKGROUND

Experimental research suggests that females have a higher survival rate after trauma, although this claim is controversial. This study sought to determine the role of sex on mortality among trauma patients in China.

METHODS

The study enrolled 1789 trauma patients who visited the Emergency Intensive Care Unit of the First Affiliated Hospital of Zhengzhou University during 2015 and 2016. A retrospective data analysis was performed to determine sex-based differences after blunt trauma. Patients were stratified by age and injury severity (using the Injury Severity Score). Multiple logistic regression was used to analyze the association between sex and post-injury complications and mortality.

RESULTS

Female trauma patients experienced a significantly lower risk of mortality than males (odds ratio, 0.931; 95% confidence interval, 0.883-0.982). This survival advantage of females was particularly notable in the 'younger than 45 years' age group. Sex-based differences were also found in the occurrence of life-threatening complications after trauma.

CONCLUSION

This study demonstrated that females are more likely to survival after severe blunt trauma and also have less inpatient complications than men, suggesting an important role for sex hormones after severe traumatic injury.

Sex differences in the pro-inflammatory cytokine response to endotoxin unfold in vivo but not ex vivo in healthy humans

Clinical data indicate that inflammatory responses differ across sexes, but the mechanisms remain elusive. Herein, we assessed in vivo and ex vivo cytokine responses to bacterial endotoxin in healthy men and women to elucidate the role of systemic and cellular factors underlying sex differences in inflammatory responses. Participants received an i.v. injection of low-dose endotoxin (0.4 ng/kg body mass), and plasma TNF-α and IL-6 responses were analyzed over a period of 6 h. In parallel, ex vivo cytokine production was measured in endotoxin-stimulated blood samples obtained immediately before in vivo endotoxin administration. As glucocorticoids (GCs) play an important role in the negative feedback regulation of the inflammatory response, we additionally analyzed plasma cortisol concentrations and ex vivo GC sensitivity of cytokine production. Results revealed greater in vivo pro-inflammatory responses in women compared with men, with significantly higher increases in plasma TNF-α and IL-6 concentrations. In addition, the endotoxin-induced rise in plasma cortisol was more pronounced in women. In contrast, no sex differences in ex vivo cytokine production and GC sensitivity were observed. Together, these findings demonstrate major differences in in vivo and ex vivo responses to endotoxin and underscore the importance of systemic factors underlying sex differences in the inflammatory response.

Predicting survival after acute civilian penetrating brain injuries: The SPIN score

OBJECTIVE

To identify predictors associated with survival in civilian penetrating traumatic brain injury (pTBI) utilizing a contemporary, large, diverse 2-center cohort, and to develop a parsimonious survival prediction score for pTBI.

METHODS

Our cohort comprised 413 pTBI patients retrospectively identified from the local trauma registries at 2 US level 1 trauma centers, of which one was predominantly urban and the other predominantly rural. Predictors of in-hospital and 6-month survival identified in univariate and multivariable logistic regression were used to develop the simple Surviving Penetrating Injury to the Brain (SPIN) score.

RESULTS

The mean age was 33 ± 16 years and patients were predominantly male (87%). Survival at hospital discharge as well as 6 months post pTBI was 42.4%. Higher motor Glasgow Coma Scale subscore, pupillary reactivity, lack of self-inflicted injury, transfer from other hospital, female sex, lower Injury Severity Score, and lower international normalized ratio were independently associated with survival (all p < 0.001; model area under the curve 0.962). Important radiologic factors associated with survival were also identified but their addition to the full multivariable would have resulted in model overfitting without much gain in the area under the curve.

CONCLUSIONS

The SPIN score, a logistic regression-based clinical risk stratification scale estimating survival after pTBI, was developed in this large, diverse 2-center cohort. While this preliminary clinical survival prediction tool does not include radiologic factors, it may support clinical decision-making after civilian pTBI if external validation confirms the probability estimates.

Impaired Immune Response in Elderly Burn Patients: New Insights Into the Immune-senescence Phenotype

OBJECTIVE

Comparing the inflammatory and immunological trajectories in burned adults versus burned elderly patients to gain novel insights and better understanding why elderly have poor outcomes.

SUMMARY BACKGROUND DATA

Despite receiving the same treatment and clinical consideration as all other burn patients, elderly patients continue to have substantially poorer outcomes compared with adults. In light of an aging population, gaining a better understanding of their susceptibility to complications and creating new treatment strategies is imperative.

METHODS

We included 130 burn patients (94 adults: <65 years old and 36 elderly: ≥65 years old) and 10 healthy controls in this study. Immune activity and expression was assessed using bioplex at various time points. Clinical outcomes such as infection, sepsis, and mortality were prospectively collected.

RESULTS

Elderly burn patients had significantly lower burn size but significantly higher Baux scores. Morbidity and mortality was significantly increased in the elderly cohort. Immune biomarkers indicated that elderly are immune compromised and unable to respond with the expected inflammatory response during the early phase after injury. This trajectory changes to a hyperinflammatory pattern during the later phase after burn. These findings are even more pronounced when comparing sepsis versus nonsepsis patients as well as survivors versus nonsurvivors in the elderly.

CONCLUSIONS

Elderly burned patients mount a delayed immune and dampened inflammatory response early after burn injury that changes to an augmented response at later time points. Late-onset sepsis and nonsurvivors had an immune exhaustion phenotype, which may represent one of the main mediators responsible for the striking mortality in elderly.

Men and women differ in inflammatory and neuroendocrine responses to endotoxin but not in the severity of sickness symptoms

Impaired mood and increased anxiety represent core symptoms of sickness behavior that are thought to be mediated by pro-inflammatory cytokines. Moreover, excessive inflammation seems to be implicated in the development of mood/affective disorders. Although women are known to mount stronger pro-inflammatory responses during infections and are at higher risk to develop depressive and anxiety disorders compared to men, experimental studies on sex differences in sickness symptoms are scarce. Thus, the present study aimed at comparing physiological and psychological responses to endotoxin administration between men and women. Twenty-eight healthy volunteers (14 men, 14 women) were intravenously injected with a low dose (0.4 ng/kg) of lipopolysaccharide (LPS) and plasma concentrations of cytokines and neuroendocrine factors as well as negative state emotions were measured before and until six hours after LPS administration. Women exhibited a more profound pro-inflammatory response with significantly higher increases in tumor necrosis factor (TNF)-α and interleukin (IL)-6. In contrast, the LPS-induced increase in anti-inflammatory IL-10 was significantly higher in men. The cytokine alterations were accompanied by changes in neuroendocrine factors known to be involved in inflammation regulation. Endotoxin injection induced a significant increase in noradrenaline, without evidence for sex differences. The LPS-induced increase in cortisol was significantly higher in woman, whereas changes in dehydroepiandrosterone were largely comparable. LPS administration also increased secretion of prolactin, but only in women. Despite these profound sex differences in inflammatory and neuroendocrine responses, men and women did not differ in endotoxin-induced alterations in mood and state anxiety or non-specific sickness symptoms. This suggests that compensatory mechanisms exist that counteract the more pronounced inflammatory response in women, preventing an exaggerated sickness response. Disturbance of these compensatory mechanisms by environmental factors such as stress may promote the development of affective disorders in women.

Do male and female trauma patients receive the same prehospital care?: an observational follow-up study

BACKGROUND

Trauma-related mortality can be lowered by efficient prehospital care. Less is known about whether gender influences the prehospital trauma care provided. The aim of this study was to explore gender-related differences in prehospital trauma care of severely injured trauma patients, with a special focus on triage, transportation, and interventions.

METHODS

We performed a retrospective observational study based on local trauma registries and hospital and ambulance records in Stockholm County, Sweden. A total of 383 trauma patients (279 males and 104 females) > 15 years of age with an Injury Severity Score (ISS) of > 15 transported to emergency care hospitals in the Stockholm area were included.

RESULTS

Male patients had a 2.75 higher odds ratio (95 % CI, 1.2-6.2) for receiving the highest prehospital priority compared to females on controlling for injury mechanism and vital signs on scene. No significant difference between genders was detected regarding other aspects of the prehospital care provided.

CONCLUSIONS

This study indicated that prehospital prioritization among severely injured late adolescent and adult trauma patients differs between genders. Knowledge of a more diffuse presentation of symptoms in female trauma patients despite severe injury may help to adapt and improve prehospital trauma care for this group.

Gender-Specific Effects on Immune Response and Cardiac Function after Trauma Hemorrhage and Sepsis

Background

Studies in human as well as animal models indicate a gender-specific responsiveness of the immune and organ systems with regard to shock, trauma, and sepsis.

Methods

A literature review was performed.

Results

Cell-mediated immune responses and cardiovascular functions are suppressed in males following trauma hemorrhage, whereas they are maintained or even enhanced in females in the proestrus state of the estrus cycle. Experimental studies have demonstrated that divergent immune responses in males and females following adverse circulatory conditions are mediated by the gender-specific hormones testosterone and estrogen. Several clinical trials, however, failed to demonstrate a significant association of gender and inflammatory response. This may be explained by the heterogeneity of the population in terms of their hormonal status at the time of injury.

Conclusions

With regard to the underlying mechanisms, receptors for sex hormones have been identified on various immune cells, suggesting direct effects of these hormones on immune function. Alternatively, indirect effects of sex steroids such as changes in cardiovascular responses or androgen- and estrogen-synthesizing enzymes might contribute to gender-specific immune responses. Clinical studies suggest that sex hormones, such as dehydroepiandrosterone, modulate the function of peripheral blood mononuclear cells also following abdominal surgery. Thus, sex hormones, receptor antagonists, and sex steroid-synthesizing enzymes might be useful in the future for modulating the complex immune responses after trauma hemorrhage and sepsis.

Prehospital Care of Burn Patients and Trajectories on Survival

We sought to identify factors associated with the prognosis and survival of burn patients by analyzing data related to the prehospital treatment of burn patients transferred directly to the burn unit from the accident site. We also aimed to assess the role of prehospital physicians and paramedics providing care to major burn patients. This study included adult burn patients with severe burns treated between 2006 and 2010. Prehospital patient records and clinical data collected during treatment were analyzed, and the Injury Severity Scale (ISS) was calculated. Patients were grouped into two cohorts based on the presence or absence of a physician during the prehospital phase. Data were analyzed with reference to survival by multivariable regression model. Specific inclusion criteria resulted in a sample of 67 patients. The groups were comparable with regard to age, gender, and injury etiology. Patients treated by prehospital physicians (group 1, n = 49) were more severely injured than patients treated by paramedics (group 2, n = 18) in terms of total burn surface area (%TBSA) (32% vs. 17%, p = 0.033), ISS (25 vs. 8, p < 0.000), and inhalation injuries (51% vs. 16%, p = 0.013), and presented with a higher pulse rate, lower systolic blood pressure, and lower median pH. Age, gender, %TBSA, and ISS were significantly associated with survival in both groups. Survival at 30 days was associated with age, gender, the amount of intravenous fluids (in liters) received during the first 24 hours, and the final %TBSA. Variables found to be independently associated by multivariable regression model with 30 day mortality were age, female gender, and final TBSA. We identified prehospital prognostic factors affecting patient outcomes. Based on the results from this study, our current EMS system is capable of identifying seriously injured burn patients who may benefit from physician attendance at the injury scene.

Disability After Deployment Injury: Are Women and Men Service Members Different?

BACKGROUND

Civilian trauma literature suggests sexual dimorphism in outcomes after trauma. Because women represent an increasing demographic among veterans, the question remains if war trauma outcomes, like civilian trauma outcomes, differ between genders.

QUESTIONS/PURPOSES

(1) Do women service members develop different conditions resulting in long-term disability compared with men service members after injuries sustained during deployment? (2) Do women service members have more or less severe disability after deployment injury compared with men service members? (3) Are men or women more likely to return to duty after combat injury?

METHODS

The Department of Defense Trauma Registry was queried for women injured during deployment from 2001 to 2011. The subjects were then queried in the Physical Evaluation Board database to determine each subject's return-to-duty status and what disabling conditions and disability percentages were assigned to those who did not return to duty. Frequency of disabling conditions, disability percentages, and return-to-duty rates for 368 women were compared with a previously published cohort of 450 men service members, 378 of whom had orthopaedic injuries.

RESULTS

Women who were unable to return to duty had a higher frequency of arthritic conditions (58% [48 of 83] of women versus 35% [133 of 378] of men, p=0.002; relative risk [RR], 1.64; 95% confidence interval [CI], 1.307-2.067) and lower frequencies of general chronic pain (1% [one of 83] of women versus 19% [59 of 378] of men, p<0.001; RR, 0.08; 95% CI, 0.011-0.549) and neurogenic pain disorders (1% [one of 83] of women versus 7% [27 of 378] of men, p=0.0410; RR, 0.169; 95% CI, 0.023-1.224). Women had more severely rated posttraumatic stress disorder (PTSD) compared with men (38%±23% versus 19%±17%). Forty-eight percent (64 of 133) of battle-injured women were unable to return to active duty, resulting in a lower return-to-duty rate compared with men (34% [450 of 1333]; p=0.003).

CONCLUSIONS

After deployment-related injury, women have higher rates of arthritis, lower rates of pain disorders, and more severely rated PTSD compared with men. Women are unable to return to duty more often than men injured in combat. These results suggest some difference between men's and women's outcomes after deployment injury, important information for military and Veterans Administration providers seeking to minimize postdeployment disability.

LEVEL OF EVIDENCE

Level III, prognostic study.

Predictors of 1 year mortality in adult injured patients admitted to the trauma center

BACKGROUND

Traditional approach to predicting trauma-related mortality utilizes scores based on anatomical, physiological, or a combination of both types of criteria. However, several factors are reported in literature to predict mortality independent of severity scores. The objectives of the study were to identify predictors of 1 year mortality and determine their magnitude and significance of association in a resource constrained scenario.

MATERIALS AND METHODS

Prospective observational study enrolled 572 patients. Information regarding factors known to affect mortality was recorded. Other factors which may be important in resource constrained settings were also included. This included referral from a peripheral hospital, number of surgeries performed on the patient, and his socioeconomic status (below poverty line (BPL) card). Patients were followed till death or upto a period of 1year. Logistic regression, actuarial survival analysis, and Cox proportionate hazard model were used to identify predictors of 1year mortality. Limited estimate of external validity of the study was obtained using bootstrapping.

RESULTS

Age of patient, Injury Severity Score (ISS), abnormal activated partial thromboplastin time (APTT), Glasgow Coma Scale (GCS) score at admission, and systolic blood pressure (BP) at admission were found to significantly predict mortality on logistic regression and Cox proportionate hazard models. Abnormal respiratory rate at admission was found to significantly predict mortality in the logistic regression model, but no such association was seen in Cox proportionate hazard model. Bootstrapping of the logistic regression model and Cox proportionate hazard model provide us with a set of factors common to both the models. These were age, ISS, APTT, and GCS score at admission.

CONCLUSION

Multivariate analysis (logistic and Cox proportionate hazard analysis) and subsequent bootstrapping provide us with a set of factors which may be considered as valid predictors universally. However, since bootstrapping only provides limited estimates of external validity, there is a need to test these factors against the well accepted requirements of external validity namely population, ecological, and temporal validity.

Association between male sex and increased mortality after falls

OBJECTIVES

Whether sex affects the mortality of trauma patients remains unknown. The hypothesis of this study was that sex was associated with altered mortality rates in trauma.

METHODS

A retrospective review of trauma patients' records in the Japan Trauma Data Bank was conducted (n = 80,813) from 185 major emergency hospitals across Japan. The primary outcome variable was in-hospital mortality within 28 days. Secondary outcome variables included serious injuries to different body regions with an Abbreviated Injury Scale of ≥3.

RESULTS

In the analysis of 80,813 trauma patients, males had significantly greater 28-day mortality compared to females (adjusted p = 0.0072, odds ratio [OR] = 1.14, 95% confidence interval [CI] = 1.06 to 1.23) via logistic regression analysis adjusted for age, mechanism, Injury Severity Score, Revised Trauma Score, and potential preexisting risk factors. Of 10 injury categories examined, sex significantly affected in-hospital 28-day mortality rate in falls (adjusted p < 0.0001, OR = 1.34, 95% CI = 1.19 to 1.52). Further analysis of three fall subcategories by falling distance revealed that male patients who fell from ground level had significantly higher 28-day mortality (adjusted p < 0.0001, OR = 1.75, 95% CI = 1.43 to 2.14) and a significantly greater frequency of serious injury to the head, thorax, abdomen, and spine, but a lower frequency of serious injury to the extremities, compared to female patients.

CONCLUSIONS

Compared to female trauma patients, male trauma patients had greater 28-day mortality. In particular, ground-level falls had a significant sex difference in mortality, with serious injury to different body regions. Sex differences appeared to be important for fatalities from ground-level falls.