Rebecca Schroll

A multi-institutional analysis of prehospital tourniquet use

BACKGROUND Recent military studies demonstrated an association between prehospital tourniquet use and increased survival. The benefits of this prehospital intervention in a civilian population remain unclear. The aims of our study were to evaluate tourniquet use in the civilian population and to compare outcomes to previously published military experience. We hypothesized that incorporation of tourniquet use in the civilian population will result in an overall improvement in mortality. METHODS This is a preliminary multi-institutional retrospective analysis of prehospital tourniquet (MIA-T) use of patients admitted to nine urban Level 1 trauma centers from January 2010 to December 2013. Patient demographics and mortality from a previous military experience by Kragh et al. (Ann Surg. 2009;249:1–7) were used for comparison. Patients younger than 18 years or with nontraumatic bleeding requiring tourniquet application were excluded. Data were analyzed using a two-tailed unpaired Student’s t test with p < 0.05 as significant. RESULTS A total of 197 patients were included. Tourniquets were applied effectively in 175 (88.8%) of 197 patients. The average Injury Severity Score (ISS) for MIA-T versus military was 11 ± 12.5 versus 14 ± 10.5, respectively (p = 0.02). The overall mortality and limb amputation rates for the MIA-T group were significantly lower than previously seen in the military population at 6 (3.0%) of 197 versus 22 (11.3%) of 194 (p = 0.002) and 37 (18.8%) of 197 versus 97 (41.8%) of 232 (p = 0.0001), respectively. CONCLUSION Our study is the largest evaluation of prehospital tourniquet use in a civilian population to date. We found that tourniquets were applied safely and effectively in the civilian population. Adaptation of this prehospital intervention may convey a survival benefit in the civilian population. LEVEL OF EVIDENCE Epidemiologic study, level V.

Multicenter evaluation of temporary intravascular shunt use in vascular trauma.

BACKGROUND The indications and outcomes associated with temporary intravascular shunting (TIVS) for vascular trauma in the civilian sector are poorly understood. The objective of this study was to perform a contemporary multicenter review of TIVS use and outcomes. METHODS Patients sustaining vascular trauma, requiring TIVS insertion (January 2005 to December 2013), were retrospectively identified at seven Level I trauma centers. Clinical demographics, operative details, and outcomes were abstracted. RESULTS A total of 213 injuries (2.7%; 94.8% arterial) requiring TIVS were identified in 7,385 patients with vascular injuries. Median age was 27.0 years (range, 4–89 years), 91.0% were male, Glasgow Coma Scale (GCS) score was 15.0 (interquartile range, 4.0), Injury Severity Score (ISS) was 16.0 (interquartile range, 15.0), 26.0% had an ISS of 25 or greater, and 71.1% had penetrating injuries. The most common mechanism was gunshot wound (62.7%), followed by auto versus pedestrian (11.4%) and motor vehicle collision (6.5%). Shunts were placed for damage control in 63.4%, staged repair for combined orthopedic and vascular injuries in 36.1%, and for insufficient surgeon skill set in 0.5%. The most common vessel shunted was the superficial femoral artery (23.9%), followed by popliteal artery (18.8%) and brachial artery (13.2%). An argyle shunt (81.2%) was the most common conduit, followed by Pruitt-Inahara (9.4%). Dwell time was less than 6 hours in 61.4%, 24 hours in 86.5%, 48 hours in 95.9%, with only 4.1% remaining in place for more than 48 hours. Of the patients, 81.6% survived to definitive repair, and 79.6% survived overall. Complications included shunt thrombosis (5.6%) and dislodgment (1.4%). There was no association between dwell time and shunt thrombosis. The use of a noncommercial shunt (chest tube/feeding tube) did not impact shunt thrombosis but was an independent risk factor for subsequent graft failure. The limb salvage rate was 96.3%. No deaths could be attributed to a shunt complication. CONCLUSION In the largest civilian TIVS experience insertion to date, both damage control and staged orthopedic vascular injuries were common indications for shunting. With an acceptable complication burden and no associated mortality attributed to this technique, shunting should be considered a viable treatment option. LEVEL OF EVIDENCE Therapeutic study, level V.

Role of computed tomography angiography in the management of Zone II penetrating neck trauma in patients with clinical hard signs.

BACKGROUND The Western Trauma Association (WTA) describes the management of Zone 2 penetrating neck trauma (PNT) and recommends neck exploration (NE) for patients with clinical hard signs (HS). We hypothesize that in stable patients with HS, the management of PNT augmented by computed tomography angiography (CTA) results in fewer negative NE results. METHODS This was a 4-year retrospective review of adult patients with Zone 2 PNT at a Level I trauma center. Stable patients with WTA-defined HS (airway compromise, massive subcutaneous emphysema/air bubbling through wound, expanding/pulsatile hematoma, active bleeding, shock, focal neurologic deficit, and hematemesis) who underwent CTA instead of emergent exploration were identified. Sensitivity, specificity, positive predictive value, and negative predictive value for CTA were calculated. A comparison was made between the rates of negative NE results in patients with HS who received a CTA versus the rate that would have occurred in the same patients if the WTA algorithm had been followed. Missed injury rates were also compared. RESULTS Of 183 PNT patients, 23 had HS and underwent CTA. Of the 23, 5 had a positive CTA findings and underwent NE, while 17 had a negative CTA findings and did not require NE. There was one false-negative in a patient who developed an expanding hematoma following negative neck CTA finding. Sensitivity, specificity, positive predictive value, and negative predictive value for CTA in the presence of HS were found to be 83%, 100%, 100%, and 94%, respectively. The addition of CTA to the WTA algorithm for this patient group significantly decreased the rate of negative NE (0 of 23 vs. 18 of 23, p < 0.001) without a significant increase in the rate of missed injury (1 of 23 vs. 0 of 23, p = 0.323). The use of CTA prevented 17 unnecessary NEs. CONCLUSION CTA addition to the management of hemodynamically stable patients with HS in PNT significantly decreased the rate of negative NE result without increasing missed injury rate. Prospective study of CTA addition to the WTA algorithm is needed. LEVEL OF EVIDENCE Care management/therapeutic study, level IV.

Multi-institutional analysis of neutrophil-to-lymphocyte ratio (NLR) in patients with severe hemorrhage: A new mortality predictor value

BACKGROUND The neutrophil/lymphocyte ratio (NLR) has been associated as a predictor for increased mortality in critically ill patients. We sought to determine the relationship between NLR and outcomes in adult trauma patients with severe hemorrhage requiring the initiation of massive transfusion protocol (MTP). We hypothesized that the NLR would be a prognostic indicator of mortality in this population. METHODS This was a multi-institutional retrospective cohort study of adult trauma patients (≥18 years) with severe hemorrhage who received MTP between November 2014 and November 2015. Differentiated blood cell counts obtained at days 3 and 10 were used to obtain NLR. Receiver operating characteristic (ROC) curve analysis assessed the predictive capacity of NLR on mortality. To identify the effect of NLR on survival, Kaplan-Meier (KM) survival analysis and Cox regression models were used. RESULTS A total of 285 patients with severe hemorrhage managed with MTP were analyzed from six participating institutions. Most (80%) were men, 57.2% suffered blunt trauma. Median (IQR) age, Injury Severity Score, and Glasgow Coma Scale were 35 (25–47), 25 (16–36), and 9 (3–15), respectively. Using ROC curve analysis, optimal NLR cutoff values of 8.81 at day 3 and 13.68 at day 10 were calculated by maximizing the Youden index. KM curves at day 3 (p = 0.05) and day 10 (p = 0.02) revealed an NLR greater than or equal to these cutoff values as a marker for increased in-hospital mortality. Cox regression models failed to demonstrate an NLR over 8.81 as predictive of in-hospital mortality at day 3 (p = 0.056) but was predictive for mortality if NLR was greater than 13.68 at day 10 (p = 0.036). CONCLUSIONS NLR is strongly associated with early mortality in patients with severe hemorrhage managed with MTP. Further research is needed to focus on factors that can ameliorate NLR in this patient population. LEVEL OF EVIDENCE Prognostic study, level III.

Implications of the Trauma Quality Improvement Project inclusion of nonsurvivable injuries in performance benchmarking

BACKGROUND The Trauma Quality Improvement Project (TQIP) uses an injury prediction model for performance benchmarking. We hypothesize that at a Level I high-volume penetrating trauma center, performance outcomes will be biased due to inclusion of patients with nonsurvivable injuries. METHODS Retrospective chart review was conducted for all patients included in the institutional TQIP analysis from 2013 to 2014 with length of stay (LOS) less than 1 day to determine survivability of the injuries. Observed (O)/expected (E) mortality ratios were calculated before and after exclusion of these patients. Completeness of data reported to TQIP was examined. RESULTS Eight hundred twenty-six patients were reported to TQIP including 119 deaths. Nonsurvivable injuries accounted 90.9% of the deaths in patients with an LOS of 1 day or less. The O/E mortality ratio for all patients was 1.061, and the O/E ratio after excluding all patients with LOS less than 1 day found to have nonsurvivable injuries was 0.895. Data for key variables were missing in 63.3% of patients who died in the emergency department, 50% of those taken to the operating room and 0% of those admitted to the intensive care unit. Charts for patients who died with LOS less than 1 day were significantly more likely than those who lived to be missing crucial. CONCLUSION This study shows TQIP inclusion of patients with nonsurvivable injuries biases outcomes at an urban trauma center. Missing data results in imputation of values, increasing inaccuracy. Further investigation is needed to determine if these findings exist at other institutions, and whether the current TQIP model needs revision to accurately identify and exclude patients with nonsurvivable injuries. Level of Evidence Prognostic and epidemiological, level III.BACKGROUND The Trauma Quality Improvement Project (TQIP) uses an injury prediction model for performance benchmarking. We hypothesize that at a level 1 high-volume penetrating trauma center, performance outcomes will be biased due to inclusion of patients with non-survivable injuries. METHODS Retrospective chart review was conducted for all patients included in the institutional TQIP analysis from 2013-2014 with length of stay (LOS) < 1 day to determine survivability of the injuries. O/E (observed-to-expected) mortality ratios were calculated before and after exclusion of these patients. Completeness of data reported to TQIP was examined. RESULTS 826 patients were reported to TQIP including 119 deaths. Non-survivable injuries accounted 90.9% of the deaths in patients with LOS ≤ 1 day. The O/E mortality ratio for all patients was 1.061, and the O/E ratio after excluding all patients with LOS <1 found to have non-survivable injuries was 0.895. Data for key variables were missing in 63.3% of patients who died in the ED, 50% of those taken to the OR and 0% of those admitted to the ICU. Charts for patients who died with LOS <1 day were significantly more likely than those who lived to be missing crucial. CONCLUSION This study shows TQIP inclusion of patients with non-survivable injuries biases outcomes at an urban trauma center. Missing data results in imputation of values, increasing inaccuracy. Further investigation is needed to determine if these findings exist at other institutions, and whether the current TQIP model needs revision to accurately identify and exclude patients with non-survivable injuries. LEVEL OF EVIDENCE Level III, prognostic and epidemiological.