Risk factors for thromboembolic complications in isolated severe head injury.

PURPOSE: Patients with traumatic brain injury (TBI) are at high risk for venous thromboembolism (VTE). The aim of the present study is to identify factors independently associated with VTE events. Specifically, we hypothesized that the mechanism of penetrating head trauma might be an independent factor associated with increased VTE events when compared with blunt head trauma. METHODS: The ACS-TQIP database (2013-2019) was queried for all patients with isolated severe head injuries (AIS 3-5) who received VTE prophylaxis with either unfractionated heparin or low-molecular-weight heparin. Transfers, patients who died within 72 h and those with a hospital length of stay < 48 h were excluded. Multivariable analysis was used as the primary analysis to identify independent risk factors for VTE in isolated severe TBI. RESULTS: A total of 75,570 patients were included in the study, 71,593 (94.7%) with blunt and 3977 (5.3%) with penetrating isolated TBI. Penetrating trauma mechanism (OR 1.49, CI 95% 1.26-1.77), increasing age (age 16-45: reference; age > 45-65: OR 1.65, CI 95% 1.48-1.85; age > 65-75: OR 1.71, CI 95% 1.45-2.02; age > 75: OR 1.73, CI 95% 1.44-2.07), male gender (OR 1.53, CI 95% 1.36-1.72), obesity (OR 1.35, CI 95% 1.22-1.51), tachycardia (OR 1.31, CI 95% 1.13-1.51), increasing head AIS (AIS 3: reference; AIS 4: OR 1.52, CI 95% 1.35-1.72; AIS 5: OR 1.76, CI 95% 1.54-2.01), associated moderate injuries (AIS = 2) of the abdomen (OR 1.31, CI 95% 1.04-1.66), spine (OR 1.35, CI 95% 1.19-1.53), upper extremity (OR 1.16, CI 95% 1.02-1.31), lower extremity (OR 1.46, CI 95% 1.26-1.68), craniectomy/craniotomy or ICP monitoring (OR 2.96, CI 95% 2.65-3.31) and pre-existing hypertension (OR 1.18, CI 95% 1.05-1.32) were identified as independent risk factors for VTE complications in isolated severe head injury. Increasing GCS (OR 0.93, CI 95% 0.92-0.94), early VTE prophylaxis (OR 0.48, CI 95% 0.39-0.60) and LMWH compared to heparin (OR 0.74, CI 95% 0.68-0.82) were identified as protective factors for VTE complications. CONCLUSION: The identified factors independently associated with VTE events in isolated severe TBI need to be considered in VTE prevention measures. In penetrating TBI, an even more aggressive VTE prophylaxis management may be justified as compared to that in blunt.

Mild traumatic brain injury: not always a mild injury.

PURPOSE: In general, risk of mortality after trauma correlates with injury severity. Despite arriving in relatively stable clinical condition, however, some patients are at risk of death following mild traumatic brain injury (TBI). The study objective was delineation of patients who die in-hospital following mild isolated TBI in order to inform Emergency Department (ED) disposition and care discussions with patients and families. METHODS: In this retrospective cohort study, patients from the National Trauma Data Bank (NTDB) (2007-2018) were included if they were injured by blunt trauma and sustained a mild TBI (defined as Head Abbreviated Injury Scale [AIS] score of 1 or 2 and arrival Glasgow Coma Scale [GCS] score of 13-15). Exclusions were severe associated injuries (extracranial AIS > 2); transfers; and missing data. Patients were defined by in-hospital mortality: Survivors vs. Mortalities. Demographics, clinical/injury data, and the outcomes were collected and compared with univariate analysis. Multivariate analysis established independent factors associated with in-hospital mortality following mild TBI. RESULTS: In total, 932,107 patients (10% of NTDB population) met study criteria: 928,542 (99.6%) Survivors and 3,565 (0.4%) Mortalities. In general, comorbidities (including home anticoagulation, cardiac disease, and diabetes mellitus) were significantly more common among patients who died (p < 0.001), although drug and alcohol intoxication on arrival were more common among Survivors (16% vs. 7%, p < 0.001; 13% vs. 10%, p < 0.001). In terms of insurance status, Private/Commercial insurance was more common among Survivors (39% vs. 20%, p < 0.001) while Governmental Insurance was more common among Mortalities (55% vs. 36%, p < 0.001). On multivariate analysis, age ≥ 65 was most strongly associated with death (OR 26.43, p < 0.001), followed by ED intubation (OR 10.08, p < 0.001), admission hypotension (OR 4.55, p < 0.001), and comorbidities, particularly end-stage renal disease (ESRD) (OR 3.03, p < 0.001) and immunosuppression (OR 2.18, p < 0.001). CONCLUSIONS: Survivors differed substantially from Mortalities after mild TBI in terms of comorbidities, intoxicants, and insurance status. Independent variables most strongly associated with in-hospital death following mild head injury included age ≥ 65, intubation in the ED, admission hypotension, and comorbidities (particularly ESRD and immunosuppression). Increased clinical vigilance, including a mandatory period of clinical observation, for patients with these risk factors should be considered to optimize outcomes and potentially mitigate death after mild TBI.

Undertriage of Severely Injured Trauma Patients.

INTRODUCTION: The American College of Surgeons (ACS) delineates trauma team activation (TTA) criteria to identify seriously injured trauma patients in the field. Patients are deemed to be severely undertriaged (SU), placing them at risk for adverse outcomes, when they do not meet TTA criteria but nonetheless sustain significant injuries (Injury Severity Score [ISS] ≥25). OBJECTIVES: Delineate patient demographics, injuries, and outcomes after SU. PARTICIPANTS: Trauma patients presenting to our ACS-verified Level 1 trauma center with ISS ≥25 were included (11/2015-03/2022). Transfers and private vehicle transports were excluded. Patients were dichotomized and compared by trauma arrival level: TTA (Appropriately Triaged, AT) vs routine consults (SU). RESULTS: Study criteria were satisfied by 1653 patients: 1375 (83%) AT and 278 (17%) SU. Severely undertriaged patients were older than AT patients (47 vs 36 years, P < .001). Severely undertriaged occurred almost exclusively following blunt trauma (96% vs 71%, P < .001). Injury Severity Score was lower following SU than AT (29 vs 32, P < .001). The most common severe injuries (Abbreviated Injury Scale score [AIS] ≥3) among the SU group were in the Chest (n = 179, 64%). Severely undertriaged patients necessitated emergent intubation (n = 34, 12%), surgery (n = 59, 21%), and angioembolization (n = 22, 8%) at high rates. Severely undertriaged mortality was n = 40, 14%. CONCLUSION: Severely undertriaged occurred among a substantial proportion of ISS ≥25 patients, predominately following blunt trauma. Severe chest injuries were most likely to evade capture. Rates of intubation, emergent intervention, and in-hospital mortality were high after SU. Efforts should be made to identify such patients in the field as they may benefit from TTA.

Does mortality after trauma team activation peak at shift change?

BACKGROUND: Prior institutional data have demonstrated trauma mortality to be highest between 06:00-07:59 at our center, which is also when providers change shifts (07:00-07:30). The objective was definition of patient, provider, and systems variables associated with trauma mortality at shift change among patients arriving as trauma team activations (TTA). METHODS: All TTA patients at our ACS-verified Level I trauma center were included (01/2008-07/2019), excluding those with undocumented arrival time. Study groups were defined by arrival time: shift change (SC) (06:00-07:59) vs. non-shift change (NSC) (all other times). Univariable/multivariable analyses compared key variables. Propensity score analysis compared outcomes after matching. RESULTS: After exclusions, 6020 patients remained: 229 (4%) SC and 5791 (96%) NSC. SC mortality was 25% vs. 16% during NSC (p < 0.001). More SC patients arrived with SBP <90 (19% vs. 11%, p < 0.001) or GCS <9 (35% vs. 24%, p < 0.001). ISS was higher during SC (43[32-50] vs. 34[27-50], p < 0.001). Time to CT scan (36[23-66] vs. 38[23-61] minutes, p = 0.638) and emergent surgery (94[35-141] vs. 63[34-107] minutes, p = 0.071) were comparable. Older age (p < 0.001), SBP <90 (p < 0.001), GCS <9 (p < 0.001), need for emergent operative intervention (p = 0.044), and higher ISS (p < 0.001) were independently associated with mortality. After propensity score matching, mortality was no different between SC and NSC (p = 0.764). CONCLUSIONS: Early morning is a low-volume, high-mortality time for TTAs. Increased mortality at shift change was independently associated with patient/injury factors but not provider/systems factors. Ensuring ample clinical resource allocation during this high acuity time may be prudent to streamline patient care at shift change.

Complications Following Temporary Bilateral Internal Iliac Artery Ligation for Pelvic Hemorrhage Control in Trauma.

Background: Temporary bilateral internal iliac artery ligation (TBIIAL) is an option for surgical control of pelvic hemorrhage after trauma. Concerns persist that complications, particularly gluteal necrosis, following TBIIAL should preclude its use, despite a lack of formal research on TBIIAL complications. This study aimed to define complications following TBIIAL for emergent control of traumatic pelvic bleeding.Study Design: Patients undergoing TBIIAL after blunt trauma (2008-2020) at our level 1 trauma center were included without exclusions. Demographics, clinical/injury data, and outcomes were collected. Descriptive statistics summarized study variables. Multivariable analysis of factors independently associated with mortality after TBIIAL was performed.Results: In total, 77 patients undergoing emergent TBIIAL after blunt trauma were identified. Median age was 46 [IQR 29-63] years. Most patients (n = 70, 91%) were severely injured (ISS ≥16), with 43% undergoing resuscitative thoracotomy prior to TBIIAL. No local complications (gluteal necrosis, iatrogenic injury, fascial dehiscence, surgical site infection) after TBIIAL occurred over the 13-year study period. In the first 28 days after injury, median hospital-, ICU-, and ventilator-free days were 0. Mortality was 70% (n = 54). On multivariable analysis, older age was the only variable independently associated with in-hospital mortality (OR 1.081, P = .028).Conclusion: Zero cases of gluteal necrosis, iatrogenic injury to surrounding structures, or surgical site infection/fascial dehiscence of the exploratory laparotomy occurred over the study period. High concern for gluteal necrosis after TBIIAL in severely injured trauma patients is unfounded and should not prevent a surgeon from obtaining prompt pelvic hemorrhage control with this technique among patients in extremis.

Destructive colon injuries requiring resection: Is colostomy ever indicated?

BACKGROUND: The management of destructive colon injuries requiring resection has shifted from mandatory diverting stoma to liberal use of primary anastomosis. Various risk criteria have been suggested for the selection of patients for primary anastomosis or ostomy. At our center, we have been practicing a policy of liberal primary anastomosis irrespective of risk factors. The purpose of this study was to evaluate the colon-related outcomes in patients managed with this policy. METHODS: This retrospective study included all colon injuries requiring resection. Data collected included patient demographics, injury characteristics, blood transfusions, operative findings, operations performed, complications, and mortality. RESULTS: A total of 287 colon injuries were identified, 101 of whom required resection, forming the study population. The majority (63.4%) were penetrating injuries. Furthermore, 16.8% were hypotensive on admission, 40.6% had moderate or severe fecal spillage, 35.6% received blood transfusion of >4 U, and 41.6% had Injury Severity Score of >15. At index operation, 88% were managed with primary anastomosis and 12% with colon discontinuity, and one patient had stoma. Damage-control laparotomy (DCL) with temporary abdominal closure was performed in 39.6% of patients. Of these patients with DCL, 67.5% underwent primary anastomosis, 30.0% were left with colon discontinuity, and 2.5% had stoma. Overall, after the definitive management of the colon, including those patients who were initially left in colon discontinuity, only six patients (5.9%) had a stoma. The incidence of anastomotic leaks in patients with primary anastomosis at the index operation was 8.0%, and there was no colon-related mortality. The incidence of colon anastomotic leaks in the 27 patients with DCL and primary anastomosis was 11.1%, and there was no colon-related mortality. Multivariate analysis evaluating possible risk factors identified discontinuity of the colon as independent risk factor for mortality. CONCLUSION: Liberal primary anastomosis should be considered in almost all patients with destructive colon injuries requiring resection, irrespective of risk factors. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level IV.

The impact of delayed time to first CT head on functional outcomes after blunt head trauma with moderately depressed GCS.

PURPOSE: Recent work suggests patients with moderately depressed Glasgow Coma Scale (GCS) score in the Emergency Department (ED) who do not undergo immediate head CT (CTH) have delayed neurosurgical intervention and longer ED stay. The present study objective was to determine the impact of time to first CTH on functional neurologic outcomes in this patient population. METHODS: Blunt trauma patients presenting to our Level I trauma center (11/2015-10/2019) with first ED GCS 9-12 were retrospectively identified and included. Transfers and those with extracranial AIS ≥ 3 were excluded. The study population was stratified into Immediate (≤ 1 h) and Delayed (1-6 h) CTH groups based on time from ED arrival to first CTH. Outcomes included functional outcomes at hospital discharge based on the Modified Rankin Scale (mRS). RESULTS: After exclusions, 564 patients were included: 414 (73%) with Immediate CTH and 150 (27%) Delayed CTH. Both groups arrived with median GCS 11 and alcohol/drug intoxication did not differ (p > 0.05). AIS Head/Neck was comparable (3[3-4] vs. 3[3-3], p = 0.349). Time to ED disposition decision and ED exit were significantly shorter after Immediate CTH (2.8[1.5-5.3] vs. 5.2[3.6-7.5]h, p < 0.001 and 5.5[3.3-8.9] vs. 8.1[5.2-11.7]h, p < 0.001). Functional outcomes were slightly worse after Immediate CTH (mRS 2[1-4] vs. 2[1-3], p = 0.002). Subgroup analysis of patients requiring neurosurgical intervention demonstrated a greater proportion of moderately disabled patients with a lower proportion of severely disabled or dead patients after Immediate CTH as compared to Delayed CTH (51 vs. 20%, p = 0.063 and 35 vs. 60%, p = 0.122). CONCLUSIONS: Immediate CTH shortened time to disposition decision out of the ED and ED exit. Patients requiring neurosurgical intervention after Immediate CTH had improved functional outcomes when compared to those undergoing Delayed CTH. These differences did not reach statistical significance in this single-center study and, therefore, a large, multicenter study is the next step in demonstrating the potential functional outcomes benefit of Immediate CTH after blunt head trauma.

Multicenter social media community consultation for an exception from informed consent trial of the XStat device (PhoXStat trial).

INTRODUCTION: Community consultation (CC) is a key step for exception from informed consent research. Using social media to conduct CC is becoming more widely accepted but has largely been conducted by single sites. We describe our experience of a social media-based CC for a multicenter clinical trial, coordinated by the lead clinical site. METHODS: Multicenter CC was administered by the lead site and conducted in preparation for a three-site prehospital randomized clinical trial. We used Facebook and Instagram advertisements targeted to the population of interest. When "clicked," the advertisements directed individuals to study-specific websites, providing additional information and the opportunity to opt out. The lead institution and one other hospital relied on a single website, whereas the third center set up their own website. Site views were evaluated using Google analytics. RESULTS: The CC took 8 weeks to complete for each site. The advertisements were displayed 9.8 million times, reaching 332,081 individuals, of whom 1,576 viewed one of the study-specific websites. There were no requests to opt out. The total cost was $3,000. The costs per person reached were $1.88, $2.00, and $1.85 for each of the three sites. A number of site-specific issues (multiple languages, hosting of study-specific websites) were easily resolved. CONCLUSION: This study suggests that it is possible for one institution to conduct multiple, simultaneous, social media-based CC campaigns, on behalf of participating trial sites. Our results suggest that this social media CC model reaches many more potential subjects and is economical and more efficient than traditional methods. LEVEL OF EVIDENCE: Epidemiological, level IV.

Exception from informed consent trials: social-media-based community consultation campaigns are representative of target communities.

BACKGROUND: 'Community consultation' (CC) is a key step when conducting Exception From Informed Consent research. Social-media-based CC has been shown to reach more people than traditional methods, but it is unclear whether those reached are representative of the community as a whole. METHODS: This is a retrospective analysis of the CC performed in preparation for the PHOXSTAT trial. Social media advertisement campaigns were conducted in the catchment areas of the three participating trauma centers and evaluated by examining Facebook user statistics. We compared these data to georeferenced population data obtained from the U.S. Census Bureau. We examined variations in the proportion of each age group reached, by gender. RESULTS: Our social media advertisements reached a total of 332 081 individuals in Los Angeles, Birmingham, and Nashville. Although there were differences in the proportion of individuals reached within each age group and gender groups, compared with the population in each area, these were small (within 5%). In Birmingham, participants 55 to 64 years old, 25 to 34 years old, and females 18 to 24 years old were slightly over-represented (a larger proportion of individuals in this age group were reached by the social media campaign, compared with the population resident in this area). In contrast, in Nashville, female participants 45 to 64 years old, and males 25 to 64 years old were over-represented. In Los Angeles, females 45 to 64 years old, and males 25 to 64 years and over were over-represented. DISCUSSION: In conclusion, this study demonstrates that social media CC campaigns can be used to reach a sample of the community broadly representative of the population as a whole, in terms of age and gender. This finding is helpful to IRBs and investigators, as it lends further support to the use of social media to conduct CC. Further work is needed to analyze how representative community samples are in terms of other characteristics, such as race, ethnicity, and socioeconomic status. LEVEL III EVIDENCE: Economic & Value-based Evaluations.

Motor vehicle crashes in pregnancy: Maternal and fetal outcomes.

BACKGROUND: Motor vehicle crashes (MVCs) are a leading cause of death in pregnant women. Even after minor trauma, there is risk of fetal complications. The purpose of this study was to compare injuries and outcomes in pregnant with matched nonpregnant women after MVC and evaluate the incidence and type of pregnancy-related complications. METHODS: Retrospective study at a Level I trauma center included pregnant MVC patients, admitted 2009 to 2019. Pregnant patients were matched for age, seatbelt use, and airbag deployment with nonpregnant women (1:3). Gestation-related complications included uterine contractions, vaginal bleeding, emergency delivery, and fetal loss. RESULTS: During the study period, there were 6,930 MVC female admissions. One hundred forty-five (2%) were pregnant, matched with 387 nonpregnant. The seat belt use (71% in nonpregnant vs. 73% in pregnant, p = 0.495) and airbag deployment (10% vs. 6%, p = 0.098) were similar in both groups. Nonpregnant women had higher Injury Severity Score (4 vs. 1, p < 0.0001) and abdominal Abbreviated Injury Scale (2 vs. 1, p < 0.001), but a smaller proportion sustained abdominal injury (18% vs. 53%, p < 0.0001). Mortality (1% vs. 0.7%, p = 0.722), need for emergency operation (6% vs. 3%, p = 0.295) or angiointervention (0.3% vs. 0%, p = 0.540), ventilator days (3 vs. 8, p = 0.907), and intensive care unit (4 vs. 4, p = 0.502) and hospital length of stay (2 vs. 2, p = 0.122) were all similar. Overall, 13 (11.1%) patients developed gestation-related complications, most commonly uterine contractions (6.3%), need for emergency delivery (3.5%), and vaginal bleeding (1.4%). CONCLUSION: Most pregnant patients hospitalized for MVC suffered minor injuries. Pregnant women had lower Injury Severity Score and abdominal Abbreviated Injury Scale than matched nonpregnant women. However, there was still a considerable incidence of gestation-related complications. It is imperative that pregnant patients be closely monitored even after minor trauma. LEVEL OF EVIDENCE: Prognostic and epidemiological, level III.

"Safer at home": The effect of the COVID-19 lockdown on epidemiology, resource utilization, and outcomes at a large urban trauma center.

BACKGROUND: The COVID-19 pandemic has affected the entire global health care system. In California, because of a high burden of cases, a lockdown order was announced on March 19, 2020. This study investigated the impact of the lockdown on the epidemiology and outcomes of trauma admissions at the largest trauma center in Los Angeles. METHODS: A retrospective study comparing epidemiological and clinical characteristics and outcomes of trauma admissions during the lockdown period (March 20, 2020, to June 30, 2020) to a similar period in the previous year (March 20, 2019, to June 30, 2019) was performed. Data collection included demographics, mechanism of injury, prehospital transportation, substance use, injury severity, resource utilization, and outcomes. FINDINGS: There were 1,202 admissions during the lockdown period in 2020 and 1,143 during the same calendar period in 2019. Following the lockdown, there was a reduction in the automobile versus pedestrian admissions by 42.5%, motorcycle injuries by 38.7%, and bicycle accidents by 28.4% but no significant effect on the number of motor vehicle accident admissions. There was an increase in ground level falls by 32.5%, especially in the elderly group. The absolute number of gunshot wounds increased by 6.2% and knife injuries by 39.3%. Suicides increased by 38.5%. Positive testing for substance use increased by 20.9%. During the lockdown, patients suffered less severe trauma, with Injury Severity Score of <9 (p < 0.001), as well as less severe head (p = 0.001) and severe chest trauma (p < 0.001). Trauma deaths were reduced by 27.9%, and the crude overall mortality was significantly lower during the lockdown period (4.1% vs. 5.9%, p = 0.046). Intensive care unit admission rates, mechanical ventilation, and intensive care unit length of stay were all reduced. CONCLUSION: The COVID-19 lockdown in 2020 had a significant effect on the epidemiology, clinical characteristics, and critical care resource utilization of trauma admissions in a large academic trauma center. These findings may help in planning and optimization of hospital resources during the pandemic. LEVEL OF EVIDENCE: Epidemiological study, level III; Retrospective observational, level III.

Transfusion-Related Hypocalcemia After Trauma.

BACKGROUND: Hypocalcemia is cited as a complication of massive transfusion. However, this is not well studied as a primary outcome in trauma patients. Our primary outcome was to determine if transfusion of packed red blood cells (pRBC) was an independent predictor of severe hypocalcemia (ionized calcium ≤ 3.6 mg/dL). METHODS: Retrospective, single-center study (01/2004-12/2014) including all trauma patients ≥ 18 yo presenting to the ED with an ionized calcium (iCa) level drawn. Variables extracted included demographics, interventions, outcomes, and iCa. Regression models identified independent risk factors for severe hypocalcemia (SH). RESULTS: Seven thousand four hundred and thirty-one included subjects, 716 (9.8%) developed SH within 48 h of admission. Median age: 39 (Range: 18-102), systolic blood pressure: 131 (IQR: 114-150), median Glasgow Coma Scale (GCS): 15 (IQR: 10-15), Injury Severity Score (ISS): 14 (IQR: 9-24). SH patients were more likely to have depressed GCS (13 vs 15, p < 0.0001), hypotension (23.2% vs 5.1%, p < 0.0001) and tachycardia (57.0% vs 41.9%, p < 0.0001) compared to non-SH patients. They also had higher emergency operative rate (71.8% vs 29%, p < 0.0001) and higher blood administration prior to minimum iCa [pRBC: (8 vs 0, p < 0.0001), FFP: (4 vs 0, p < 0.0001), platelet: (1 vs 0, p < 0.0001)]. Multivariable analysis revealed penetrating mechanism (AOR: 1.706), increased ISS (AOR: 1.029), and higher pRBC (AOR: 1.343) or FFP administered (AOR: 1.097) were independent predictors of SH. SH was an independent predictor of mortality (AOR: 2.658). Regression analysis identified a significantly higher risk of SH at pRBC + FFP administration of 4 units (AOR: 18.706, AUC:. 897 (0.884-0.909). CONCLUSION: Transfusion of pRBC is an independent predictor of SH and is associated with increased mortality. The predicted probability of SH increases as pRBC + FFP administration increases.

Pulse Pressure as an Early Warning of Hemorrhage in Trauma Patients.

BACKGROUND: Hypotension based on low systolic blood pressure (SBP) is a well-documented indicator of ongoing blood loss. However, the utility of pulse pressure (PP) for detection of hemorrhage has not been well studied. The purpose of this study was to determine whether a narrowed PP in nonhypotensive patients is an independent predictor of critical administration threshold (CAT+) hemorrhage requiring surgical or endovascular control. STUDY DESIGN: We performed a retrospective single-center study (January 2010 to October 2014), including trauma patients ≥16 years old with SBP ≥ 90 mmHg upon emergency department (ED) admission. We identified patients who were both CAT+ and required either surgical or interventional radiology for definitive hemorrhage control as the active hemorrhage (AH) group. Analyses were then performed to elucidate the association between PP and hemorrhage. RESULTS: Of the total 18,015 patients identified, 283 (1.6%) met the criteria for clinically significant hemorrhage. Mean PP was significantly lower in the AH group compared with the non-AH group (39 ± 18 mmHg vs 53 ± 19 mmHg, p < 0.0001). Multivariate analysis revealed that narrowed initial ED PP is an independent predictor of AH (adjusted odds ratio [AOR] 0.975) along with age (AOR 1.01), penetrating mechanism (AOR 9.476), field SBP (AOR 0.985), ED heart rate (AOR 1.024), and Injury Severity Score (AOR 1.126). Cutoff analysis of PP values identified a significantly higher risk of AH at a PP cutoff of 55 mmHg (AOR 3.44, p = 0.005, AUC 0.955) in patients 61 years or older vs 40 mmHg (AOR 2.73, p < 0.0001, AUC 0.940) for patients 16 to 60 years old. The predicted probability of AH increases as PP narrows. CONCLUSIONS: In patients who are nonhypotensive, a narrowed PP is an independent early predictor of active hemorrhage requiring blood product transfusion and intervention for hemorrhage control.

Peak creatinine kinase level is a key adjunct in the evaluation of critically ill trauma patients.

BACKGROUND: Elevated creatinine kinase (CK) can indicate rhabdomyolysis, a risk factor for acute kidney injury (AKI). We investigated risk factors and clinical significance of peak CK levels. METHODS: Retrospective analysis, adult trauma patients. Logistic regression was used to identify risk factors for elevated CK and AKI. RESULTS: 3240 trauma patients were analyzed; median time to peak CK was 17 h and 347 patients had peak CK > 5000. On multivariable analysis, younger males with severe injury were more likely to have peak CK > 5000 and peak CK > 5000 was an independent risk factor for AKI (AOR 3.79). Although peak CK levels were significantly lower in older patients (1,637U/L vs 2,604U/L), older patients were more likely to develop AKI at lower CK levels. CONCLUSIONS: CK levels commonly peak within 1-2 days after admission. Despite lower peak CK levels, older patients are more likely to develop AKI. These data may support more rigorous CK monitoring and lower intervention threshold in older patients.

The diagnostic yield of commonly used investigations in pelvic gunshot wounds.

BACKGROUND: Patients who sustain pelvic gunshot wounds (GSWs) are at significant risk for injury owing to the density of pelvic structures. Currently, the optimal workup for pelvic GSWs is unclear. The aims of this study were to determine the diagnostic yield of tests commonly used in the investigation of pelvic GSWs and to develop a diagnostic algorithm. METHODS: All patients 15 years or older presenting to the Los Angeles County + University of Southern California Medical Center (January 2008 to February 2015) who sustained one or more pelvic GSWs were retrospectively identified. Patients' demographics, clinical assessment, investigations, procedures, and outcomes were abstracted. The diagnostic yield of computed tomographic (CT) scan, cystogram, gross inspection of the urine, urinalysis, endoscopy, and digital rectal examination (DRE) in the detection of clinically significant injuries to the pelvis were calculated. RESULTS: Three hundred seventy patients were included. Patients with peritonitis, hemodynamic instability, an unevaluable abdomen, or evisceration were taken to the operating room for immediate laparotomy (n = 138 [37.3%]). All others (n = 232 [62.7%]) underwent CT scan and further investigations as indicated. The sensitivity, specificity, positive predictive value, and negative predictive value of the investigations were CT scan: 1.00, 0.98, 0.74, and 1.00; cystogram: 1.00 for all parameters; gross inspection of the urine: 1.00 for all parameters; urinalysis: 1.00, 0.71, 0.17, and 1.00; endoscopy: 1.00, 0.82, 0.75, and 1.00; and DRE: 0.77, 0.99, 0.77, and 0.99. CONCLUSION: In the workup of pelvic GSWs, patients with hemodynamic instability, peritonitis, evisceration, or an unevaluable abdomen should undergo immediate laparotomy, while all others should undergo CT scan. Computed tomography-positive patients should be managed for their injuries. If the CT is negative, the likelihood of a clinically significant injury is very low. If the CT is equivocal for rectal or bladder injury, endoscopy or cystogram should be used to guide definitive management. There is no role for routine urinalysis or DRE. Further prospective validation of these findings is warranted. LEVEL OF EVIDENCE: Diagnostic study, level III; therapeutic study, level IV.

The prognostic value of neutrophil-to-lymphocyte ratio on mortality in critically ill trauma patients.

BACKGROUND: Recent studies suggest that the neutrophil-lymphocyte ratio (NLR) as a marker of inflammation is associated with mortality in surgical patients. The aim of this study was to determine the prognostic impact of NLR in critically ill trauma patients. METHODS: This is a retrospective cohort study involving all trauma patients 16 years or older admitted to the surgical intensive care unit of a Level 1 trauma center (January 2013 to January 2014). The predictive capacity of NLR on mortality was assessed using a receiver operating characteristic curve analysis. To identify the effect of the NLR on survival, a separate log-rank test was used. Multivariable Cox proportional hazard modeling was used to identify independent predictors of mortality. RESULTS: During the study period, 1,356 patients met inclusion criteria. Of these, 74% were male, 86% sustained blunt trauma, and the median age was 49 years (interquartile range [IQR], 35). The median Glasgow Coma Scale (GCS) score and Injury Severity Score (ISS) were 15 (IQR, 3) and 13 (IQR, 14), respectively. With the use of the receiver operating characteristic curve analyses at intensive care unit Days 2 and 5, optimal NLR cutoff values of 8.19 and 7.92 were calculated by maximizing the Youden index. Kaplan-Meier curves revealed an NLR greater than or equal to these cutoff values as a marker for increased in-hospital mortality (p < 0.001, log-rank test). The Cox regression model demonstrated that an NLR greater than 8.19 and 7.92 are independently associated with in-hospital mortality at Days 2 and 5, respectively (hazard ratio, 1.602 [p = 0.019] and 3.758 [p < 0.001]). CONCLUSION: NLR is associated with mortality in critically ill trauma patients. Prospective validation of its role as a predictive marker for outcomes is warranted. LEVEL OF EVIDENCE: Prognostic study, level III.

Large animal evaluation of riboflavin and ultraviolet light-treated whole blood transfusion in a diffuse, nonsurgical bleeding porcine model.

BACKGROUND: The Mirasol system has been demonstrated to effectively inactivate white blood cells (WBCs) and reduce pathogens in whole blood in vitro. The purpose of this study was to compare the safety and efficacy of Mirasol-treated fresh whole blood (FWB) to untreated FWB in an in vivo model of surgical bleeding. STUDY DESIGN AND METHODS: A total of 18 anesthetized pigs (40 kg) underwent a 35% total blood volume bleed, cooling to 33°C, and a standardized liver injury. Animals were then randomly assigned to resuscitation with either Mirasol-treated or untreated FWB, and intraoperative blood loss was measured. After abdominal closure, the animals were observed for 14 days, after which the animals were euthanized and tissues were obtained for histopathologic examination. Mortality, tissue near-infrared spectroscopy, red blood cell (RBC) variables, platelets (PLTs), WBCs, and coagulation indices were analyzed. RESULTS: Total intraoperative blood loss was similar in test and control arms (8.3 ± 3.2 mL/kg vs. 7.7 ± 3.9 mL/kg, p = 0.720). All animals survived to Day 14. Trended values over time did not show significant differences-tissue oxygenation (p = 0.605), hemoglobin (p = 0.461), PLTs (p = 0.807), WBCs (p = 0.435), prothrombin time (p = 0.655), activated partial thromboplastin time (p = 0.416), thromboelastography (TEG)-reaction time (p = 0.265), or TEG-clot formation time (p = 0.081). Histopathology did not show significant differences between arms. CONCLUSIONS: Mirasol-treated FWB did not impact survival, blood loss, tissue oxygen delivery, RBC indices, or coagulation variables in a standardized liver injury model. These data suggest that Mirasol-treated FWB is both safe and efficacious in vivo.