Joshua B. Brown

Helicopters and the civilian trauma system: national utilization patterns demonstrate improved outcomes after traumatic injury.

BACKGROUND The role of helicopter transport (HT) in civilian trauma care remains controversial. The objective of this study was to compare patient outcomes after transport from the scene of injury by HT and ground transport using a national patient sample. METHODS Patients transported from the scene of injury by HT or ground transport in 2007 were identified using the National Trauma Databank version 8. Injury severity, utilization of hospital resources, and outcomes were compared. Stepwise logistic regression was used to determine whether transport modality was a predictor of survival or discharge to home after adjusting for covariates. RESULTS There were 258,387 patients transported by helicopter (16%) or ground (84%). Mean Injury Severity Score was higher in HT patients (15.9 ± 12.3 vs. 10.2 ± 9.5, p < 0.01), as was the percentage of patients with Injury Severity Score >15 (42.6% vs. 20.8%; odds ratio [OR], 2.83; 95% confidence interval [CI], 2.76-2.89). HT patients had higher rates of intensive care unit admission (43.5% vs. 22.9%; OR, 2.58; 95% CI, 2.53-2.64) and mechanical ventilation (20.8% vs. 7.4%; OR, 3.30; 95% CI, 3.21-3.40). HT was a predictor of survival (OR, 1.22; 95% CI, 1.17-1.27) and discharge to home (OR, 1.05; 95% CI, 1.02-1.07) after adjustment for covariates. CONCLUSIONS Trauma patients transported by helicopter were more severely injured, had longer transport times, and required more hospital resources than those transported by ground. Despite this, HT patients were more likely to survive and were more likely to be discharged home after treatment when compared with those transported by ground. Despite concerns regarding helicopter utilization in the civilian setting, this study shows that HT has merit and impacts outcome.

Debunking the survival bias myth: characterization of mortality during the initial 24 hours for patients requiring massive transfusion.

BACKGROUND Controversy surrounds the optimal ratios of blood (packed red blood cell [PRBC]), plasma (fresh frozen plasma [FFP]) and platelet (PLT) use for patients requiring massive transfusion (MT) owing to possible survival bias in previous studies. We sought to characterize mortality during the first 24 hours while controlling for time varying effects of transfusion to minimize survival bias. METHODS Data were obtained from a multicenter prospective cohort study of adults with blunt injury and hemorrhagic shock. MT was defined as 10 U of PRBC or more over 24 hours. High FFP/PRBC (≥1:1.5) and PLT/PRBC (≥1:9) ratios at 6, 12, and 24 hours were compared with low ratio groups. Cox proportional hazards regression was used to determine the independent association of high versus low ratios with mortality at 6, 12, and 24 hours while controlling for important confounders. Cox proportional hazards regression was repeated with FFP/PRBC and PLT/PRBC ratios analyzed as time-dependent covariates to account for fluctuation over time. Mortality for more than 24 hours was treated as survival. RESULTS In the MT cohort (n = 604), initial base deficit, lactate, and international normalized ratio were similar across high and low ratio groups. High 6-hour FFP/PRBC and PLT/PRBC ratios were independently associated with a reduction in mortality risk at 6, 12, and 24 hours (hazard ratio [HR] range, 0.20–0.41, p < 0.05). These findings were consistent for 12-hour and 24-hour ratios. When analyzed as time-dependent covariates, a high FFP/PRBC ratio was associated with a 68% (HR, 0.32; 95% confidence interval [CI], 0.12–0.87, p = 0.03) reduction in 24-hour mortality, and a high PLT/PRBC ratio was associated with a 96% (HR, 0.04; 95% CI, 0.01–0.94, p = 0.04) reduction in 24-hour mortality. Subgroup analysis revealed that a high 1:1 ratio (≥1:1.5) had a significant 24-hour survival benefit relative to a high 1:2 (1:1.51–1:2.50) ratio group at both 6 hours (HR, 0.19; 95% CI, 0.03–0.86, p = 0.03) and 24 hours (HR, 0.25; 95% CI, 0.06–0.95, p = 0.04), suggesting a dose-response relationship. A high FFP/PRBC or PLT/PRBC ratio was not associated with development of multiple-organ failure, nosocomial infection, or adult respiratory distress syndrome in a 28-day Cox proportional hazards regression. CONCLUSION Despite similar degrees of early shock and coagulopathy, high FFP/PRBC and PLT/PRBC ratios are associated with a survival benefit as early as 6 hours and throughout the first 24 hours, even when time-dependent fluctuations of component transfusion are accounted for. This suggests that the observed mortality benefit associated with high component transfusion ratios is unlikely owing to survivor bias and that early attainment of high transfusion ratios may significantly lower the risk of mortality in MT patients. LEVEL OF EVIDENCE Therapeutic study, level II.

Pre-Trauma Center Red Blood Cell Transfusion Is Associated with Improved Early Outcomes in Air Medical Trauma Patients

BACKGROUND Hemorrhage is the leading cause of survivable death in trauma and resuscitation strategies including early RBC transfusion have reduced this. Pre-trauma center (PTC) RBC transfusion is growing and preliminary evidence suggests improved outcomes. The study objective was to evaluate the association of PTC RBC transfusion with outcomes in air medical trauma patients. STUDY DESIGN We conducted a retrospective cohort study of trauma patients transported by helicopter to a Level I trauma center from 2007 to 2012. Patients receiving PTC RBC transfusion were matched to control patients (receiving no PTC RBC transfusion during transport) in a 1:2 ratio using a propensity score based on prehospital variables. Conditional logistic regression and mixed-effects linear regression were used to determine the association of PTC RBC transfusion with outcomes. Subgroup analysis was performed for scene transport patients. RESULTS Two-hundred and forty treatment patients were matched to 480 control patients receiving no PTC RBC transfusion. Pre-trauma center RBC transfusion was associated with increased odds of 24-hour survival (adjusted odds ratio [AOR] = 4.92; 95% CI, 1.51-16.04; p = 0.01), lower odds of shock (AOR = 0.28; 95% CI, 0.09-0.85; p = 0.03), and lower 24-hour RBC requirement (Coefficient -3.6 RBC units; 95% CI, -7.0 to -0.2; p = 0.04). Among matched scene patients, PTC RBC was also associated with increased odds of 24-hour survival (AOR = 6.31; 95% CI, 1.88-21.14; p < 0.01), lower odds of shock (AOR = 0.24; 95% CI, 0.07-0.80; p = 0.02), and lower 24-hour RBC requirement (Coefficient -4.5 RBC units; 95% CI, -8.3 to -0.7; p = 0.02). CONCLUSIONS Pre-trauma center RBC was associated with an increased probability of 24-hour survival, decreased risk of shock, and lower 24-hour RBC requirement. Pre-trauma center RBC appears beneficial in severely injured air medical trauma patients and prospective study is warranted as PTC RBC transfusion becomes more readily available.

Helicopters Improve Survival in Seriously Injured Patients Requiring Interfacility Transfer for Definitive Care

BACKGROUND Helicopter transport (HT) is frequently used for interfacility transfer of injured patients to a trauma center. The benefits of HT over ground transport (GT) in this setting are unclear. By using a national sample, the objective of this study was to assess whether HT impacted outcomes following interfacility transfer of trauma patients. METHODS Patients transferred by HT or GT in 2007 were identified using the National Trauma Databank (version 8). Injury severity, resource utilization, and survival to discharge were compared. Stepwise logistic regression was used to determine whether transport modality was a predictor of survival after adjusting for covariates. Regression analysis was repeated in subgroups with Injury Severity Score (ISS)≤15 and ISS>15. RESULTS There were 74,779 patients transported by helicopter (20%) or ground (80%). Mean ISS was higher in patients transported by helicopter (17±11 vs. 12±9; p<0.01) as was the proportion with ISS>15 (49% vs. 28%; odds ratio [OR], 2.53; 95% confidence interval [CI], 2.43-2.63). Patients transported by helicopter had higher rates of intensive care unit admission (54% vs. 29%; OR, 2.86; 95% CI, 2.75-2.96), had shorter transport time (61±55 minutes vs. 98±71 minutes; p<0.01), and had shorter overall prehospital time (135±86 minutes vs. 202±132 minutes; p<0.01). HT was not a predictor of survival overall or in patients with ISS≤15. In patients with ISS>15, HT was a predictor of survival (OR, 1.09; 95% CI, 1.02-1.17; p=0.01). CONCLUSIONS Patients transported by helicopter were more severely injured and required more hospital resources than patients transported by ground. HT offered shorter transport and overall prehospital times. For patients with ISS>15, HT was a predictor of survival. These findings should be considered when developing interfacility transfer policies for patients with severe injuries.

Pretrauma Center Red Blood Cell Transfusion Is Associated with Reduced Mortality and Coagulopathy in Severely Injured Patients with Blunt Trauma

OBJECTIVE To evaluate the association of pretrauma center (PTC) red blood cell (RBC) transfusion with outcomes in severely injured patients. BACKGROUND Hemorrhage remains a major driver of mortality. Little evidence exists supporting PTC interventions to mitigate this. METHODS Blunt injured patients in shock arriving at a trauma center within 2 hours of injury were included from the Glue Grant database. Subjects were dichotomized by PTC RBC transfusion. Outcomes included 24-hour mortality, 30-day mortality, and trauma-induced coagulopathy [(TIC), admission international normalized ratio >1.5]. Cox regression and logistic regression determined the association of PTC RBC transfusion with outcomes. To address baseline differences, propensity score matching was used. RESULTS Of 1415 subjects, 50 received PTC RBC transfusion. Demographics and injury severity score were similar. The PTC RBC group received 1.3 units of RBCs (median), and 52% were scene transports. PTC RBC transfusion was associated with a 95% reduction in odds of 24-hour mortality [odds ratio (OR) = 0.05; 95% confidence interval (CI), 0.01-0.48; P < 0.01], 64% reduction in the risk of 30-day mortality [hazard ratio = 0.36; 95% CI, 0.15-0.83; P = 0.02], and 88% reduction in odds of TIC (OR = 0.12; 95% CI, 0.02-0.79; P = 0.03). The matched cohort included 113 subjects (31% PTC RBC group). Baseline characteristics were similar. PTC RBC transfusion was associated with a 98% reduction in odds of 24-hour mortality (OR = 0.02; 95% CI, 0.01-0.69; P = 0.04), 88% reduction in the risk of 30-day mortality (hazard ratio = 0.12; 95% CI, 0.03-0.61; P = 0.01), and 99% reduction in odds of TIC (OR = 0.01; 95% CI, 0.01-0.95; P = 0.05). CONCLUSIONS PTC RBC administration was associated with a lower risk of 24-hour mortality, 30-day mortality, and TIC in severely injured patients with blunt trauma, warranting further prospective study.

Mechanism of injury and special consideration criteria still matter: an evaluation of the national trauma triage protocol

BACKGROUND The Centers for Disease Control recently updated the National Trauma Triage Protocol. This field triage algorithm guides emergency medical service providers through four decision steps (physiologic [PHY], anatomic [ANA], mechanism, and special considerations) to identify patients who would benefit from trauma center care. The study objective was to analyze whether trauma center need (TCN) was accurately predicted solely by the PHY and ANA criteria using national data. METHODS Trauma patients aged 18 years and older were identified in the NTDB (2002-2006). PHY data and ANA injuries (International Classification of Diseases, ninth revision codes) were collected. TCN was defined as Injury Severity Score (ISS)>15, intensive care unit admission, or need for urgent surgery. Test characteristics were calculated according to steps in the triage algorithm. Logistic regression was performed to determine independent association of criteria with outcomes. Receiver operating characteristic curves were constructed for each model. RESULTS A total of 1,086,764 subjects were identified. Sensitivity of PHY criteria was highest for ISS>15 (42%) and of ANA criteria for urgent surgery (37%). By using PHY and ANA steps, sensitivity was highest (56%) and undertriage lowest (45%) for ISS>15. Undertriage for TCN based on actual treating trauma center level was 11%. CONCLUSION Current PHY and ANA criteria are highly specific for TCN but result in a high degree of undertriage when applied independently. This implies that additional factors such as mechanism of injury and the special considerations included in the Centers for Disease Control decision algorithm contribute significantly to the effectiveness of this field triage tool.

Does the need for noncardiac surgery during ventricular assist device therapy impact clinical outcome

BACKGROUND The role of the ventricular assist device (VAD) in the management of heart failure is expanding. Despite its success, the clinical course for patients requiring noncardiac surgery (NCS) during VAD support is not well described. The objective of this study was to identify VAD patients requiring NCS (+NCS) and compare outcomes with those not requiring NCS (-NCS). METHODS Patients undergoing VAD implant from 2000 to 2007 were reviewed. NCS procedures, survival, and complications were collected. Survival at 1 year from implant, overall survival at the study conclusion, survival time from implant, and outcome of VAD therapy were compared between groups. RESULTS We enrolled 142 subjects. Demographics did not differ between groups. Twenty-five subjects (18%) underwent 27 NCS procedures. Perioperative survival was 100% and 28-day survival was 64%. Survival to discharge was 56%. Bleeding occurred in 48%. Infection occurred in 33%. Estimated blood loss was 355 mL, and the international normalized ratio at time of NCS was 1.9. Laparoscopy was performed in 3 cases. There was no difference in 1-year survival (59% vs 54%), survival at study conclusion (44% vs 46%) or survival time (517 vs 523 days) between +NCS subjects and -NCS subjects. There were similar causes of death in both groups. The +NCS group was on VAD support longer (245 vs 87 days; P < .01), and less likely to undergo heart transplantation (12% vs 35%; P < .01). CONCLUSION NCS is not uncommon during VAD therapy. Bleeding and infection were common complications. Despite this, NCS seems to be feasible and safe and does not seem to increase mortality in the VAD population.

Systolic blood pressure criteria in the National Trauma Triage Protocol for geriatric trauma: 110 is the new 90.

BACKGROUND Undertriage is a concern in geriatric patients. The National Trauma Triage Protocol (NTTP) recognized that systolic blood pressure (SBP) less than 110 mm Hg may represent shock in those older than 65 years. The objective was to evaluate the impact of substituting an SBP of less than 110 mm Hg for the current SBP of less than 90 mm Hg criterion within the NTTP on triage performance and mortality. METHODS Subjects undergoing scene transport in the National Trauma Data Bank (2010–2012) were included. The outcome of trauma center need was defined as Injury Severity Score (ISS) greater than 15, intensive care unit admission, urgent operation, or emergency department death. Geriatric (age > 65 years) and adult (age, 16–65 years) cohorts were compared. Triage characteristics and area under the curve (AUC) were compared between SBP of less than 110 mm Hg and SBP of less than 90 mm Hg. Hierarchical logistic regression was used to determine whether geriatric patients newly triaged positive under this change (SBP, 90–109 mm Hg) have a risk of mortality similar to those triaged positive with SBP of less than 90 mm Hg. RESULTS There were 1,555,944 subjects included. SBP of less than 110 mm Hg had higher sensitivity but lower specificity in geriatric (13% vs. 5%, 93% vs. 99%) and adult (23% vs. 10%, 90% vs. 98%) cohorts. AUC was higher for SBP of less than 110 mm Hg individually in both geriatric and adult (p < 0.01) cohorts. Within the NTTP, the AUC was similar for SBP of less than 110 mm Hg and SBP of less than 90 mm Hg in geriatric subjects but was higher for SBP of less than 90 mm Hg in adult subjects (p < 0.01). Substituting SBP of less than 110 mm Hg resulted in an undertriage reduction of 4.4% with overtriage increase of 4.3% in the geriatric cohort. Geriatric subjects with SBP of 90 mm Hg to 109 mm Hg had an odds of mortality similar to those of geriatric patients with SBP of less than 90 mm Hg (adjusted odds ratio, 1.03; 95% confidence interval, 0.88–1.20; p = 0.71). CONCLUSION SBP of less than 110 mm Hg increases sensitivity. SBP of less than 110 mm Hg has discrimination as good as that of SBP of less than 90 mm Hg, with superior improvements in undertriage relative to overtriage in geriatric patients. Geriatric patients newly triaged to be positive under this change have a risk of mortality similar to those under the current SBP criterion. This change in SBP criteria may be merited in geriatric patients, warranting further study to consider elevation to a Step 1 criterion in the NTTP. LEVEL OF EVIDENCE Diagnostic study, level IV.

Goal Directed Resuscitation in the Prehospital Setting: A Propensity Adjusted Analysis

BACKGROUND: The scope of prehospital (PH) interventions has expanded recently—not always with clear benefit. PH crystalloid resuscitation has been challenged, particularly in penetrating trauma. Optimal PH crystalloid resuscitation strategies remain unclear in blunt trauma as does the influence of PH hypotension. The objective was to characterize outcomes for PH crystalloid volume in patients with and without PH hypotension. METHODS: Data were obtained from a multicenter prospective study of blunt injured adults transported from the scene with ISS > 15. Subjects were divided into HIGH (>500 mL) and LOW (<=500 mL) PH crystalloid groups. Propensity‐adjusted regression determined the association of PH crystalloid group with mortality and acute coagulopathy (admission International Normalized Ratio, >1.5) in subjects with and without PH hypotension (systolic blood pressure [SBP], <90 mm Hg) after controlling for confounders. RESULTS: Of 1,216 subjects, 822 (68%) received HIGH PH crystalloid and 616 (51%) had PH hypotension. Initial base deficit and ISS were similar between HIGH and LOW crystalloid groups in subjects with and without PH hypotension. In subjects without PH hypotension, HIGH crystalloid was associated with an increase in the risk of mortality (hazard ratio, 2.5; 95% confidence interval [95% CI], 1.3–4.9; p < 0.01) and acute coagulopathy (odds ratio [OR], 2.2; 95% CI, 1.01–4.9; p = 0.04) but not in subjects with PH hypotension. HIGH crystalloid was associated with correction of PH hypotension on emergency department (ED) arrival (OR, 2.02; 95% CI, 1.06–3.88; p = 0.03). The mean corrected SBP in the ED was 104 mm Hg. Each 1 mm Hg increase in ED SBP was associated with a 2% increase in survival in subjects with PH hypotension (OR, 1.02; 95% CI, 1.01–1.03; p < 0.01). CONCLUSION: In severely injured blunt trauma patients, PH crystalloid more than 500 mL was associated with worse outcome in patients without PH hypotension but not with PH hypotension. HIGH crystalloid was associated with corrected PH hypotension. This suggests that PH resuscitation should be goal directed based on the presence or absence of PH hypotension. LEVEL OF EVIDENCE: Therapeutic study, level III.

The swinging pendulum: a national perspective of nonoperative management in severe blunt liver injury.

BACKGROUND Despite a shift toward nonoperative management (NOM) of blunt liver trauma, severe injuries continue to require operative management. Our objective was to examine current trends of NOM for severe blunt liver injury from a national perspective. METHODS Patients with blunt liver injury with Abbreviated Injury Scale (AIS) score of 4 or greater and no other major solid organ injury or pelvic fracture were identified in the National Trauma Data Bank 2002 to 2008. Attempted NOM was defined as no surgery in 6 hours or less. Failed NOM was defined as surgery in greater than 6 hours. Cox regression evaluated the association of NOM outcome with 30-day mortality after controlling for injury severity and center. Logistic regression was used to define independent predictors of failed NOM. Annual attempted and failed NOM rates were compared during the study period. RESULTS A total of 3,627 patients were identified with a median Injury Severity Score (ISS) of 29 (interquartile range, 20–38) and 20% mortality. Early operative management occurred in 20%, while initial NOM occurred in 73% of the patients. Of these, 93% had successful NOM, and 7% had failed NOM. Failed NOM was an independent predictor of mortality (hazard ratio, 1.7; 95% confidence interval, 1.1–2.6; p = 0.01). Increasing age, male sex, increasing ISS, decreasing Glasgow Coma Scale (GCS) score, hypotension, and hepatic angioembolization were independent predictors of failed NOM. The rate of attempted and failed NOM increased during the study period (p < 0.01). CONCLUSION NOM for isolated severe blunt liver injury is increasing nationally with similar increment in failure. Failed NOM was associated with higher mortality. Several predictors of failed NOM were identified including age, sex, ISS, GCS, and hypotension. These factors may allow for better patient selection and improved outcomes. LEVEL OF EVIDENCE Therapeutic study, level IV; prognostic/epidemiologic study, level III.