'Door-to-prophylaxis' as a novel quality improvement metric in prevention of venous thromboembolism following traumatic injury.

Objective: Venous thromboembolism (VTE) risk reduction strategies include early initiation of chemoprophylaxis, reducing missed doses, weight-based dosing and dose adjustment using anti-Xa levels. We hypothesized that time to initiation of chemoprophylaxis would be the strongest modifiable risk for VTE, even after adjusting for competing risk factors. Methods: A prospectively maintained trauma registry was queried for patients admitted July 2017-October 2021 who were 18 years and older and received emergency release blood products. Patients with deep vein thrombosis or pulmonary embolism (VTE) were compared to those without (no VTE). Door-to-prophylaxis was defined as time from hospital arrival to first dose of VTE chemoprophylaxis (hours). Univariate and multivariate analyses were then performed between the two groups. Results: 2047 patients met inclusion (106 VTE, 1941 no VTE). There were no differences in baseline or demographic data. VTE patients had higher injury severity score (29 vs 24), more evidence of shock by arrival lactate (4.6 vs 3.9) and received more post-ED transfusions (8 vs 2 units); all p<0.05. While there was no difference in need for enoxaparin dose adjustment or missed doses, door-to-prophylaxis time was longer in the VTE group (35 vs 25 hours; p=0.009). On multivariate logistic regression analysis, every hour delay from time of arrival increased likelihood of VTE by 1.5% (OR 1.015, 95% CI 1.004 to 1.023, p=0.004). Conclusion: The current retrospective study of severely injured patients with trauma who required emergency release blood products found that increased door-to-prophylaxis time was significantly associated with an increased likelihood for VTE. Chemoprophylaxis initiation is one of the few modifiable risk factors available to combat VTE, therefore early initiation is paramount. Similar to door-to-balloon time in treating myocardial infarction and door-to-tPA time in stroke, "door-to-prophylaxis time" should be considered as a hospital metric for prevention of VTE in trauma. Level of evidence: Level III, retrospective study with up to two negative criteria.

Exposure to statin therapy decreases the incidence of venous thromboembolism after trauma.

INTRODUCTION: Venous thromboembolism (VTE) is a leading cause of morbidity and mortality in trauma patients, despite chemoprophylaxis. Statins have been shown capable of acting upon the endothelium. We hypothesized that statin therapy in the pre- or in-hospital settings leads to a decreased incidence of VTE. METHODS: We conducted a retrospective cohort study of injured patients who received statin therapy pre- or in-hospital. Adult, highest-level trauma activation patients admitted January 2018 - June 2022 were included. Patients on prehospital anticoagulants, history of inherited bleeding disorder, and who died within the first 24 hours were excluded. Statin users were matched to non-users by statin use indications including age, current heart and cardiovascular conditions and history, hyperlipidemia, injury severity, and body mass index. Time to in-hospital statin initiation and occurrence of VTE and other complications within 60 days were collected. Differences between groups were determined by univariate, multivariable logistic regression, and Cox proportional hazard analyses. RESULTS: Of 3,062 eligible patients, 79 were statin users that were matched to 79 non-users. There were no differences in admissions demographics, vital signs, injury pattern, transfusion volumes, lengths of stay, or mortality between groups. The overall VTE incidence was 10.8% (17/158). Incidence of VTE in statin users was significantly lower (3%) than non-users (19%; P = 0.003). Differences between statin users and non-users were observed for rates of DVT (0% vs 9%), PE (3% vs 15%), and sepsis (0% vs 5%). Exposure to statins was associated with an 82% decreased risk of developing VTE (hazard ratio = 0.18, 95% CI 0.04 - 0.86; P = 0.033). CONCLUSIONS: Statin exposure was associated with decline in VTE and lower individual rates of DVT, PE, and sepsis. Our findings indicate that statins should be evaluated further as a possible adjunctive therapy for VTE chemoprophylaxis after traumatic injury. LEVEL OF EVIDENCE AND STUDY TYPE: Level III, Retrospective Cohort Study.

When is it safe to start venous thromboembolism prophylaxis after blunt solid organ injury? A prospective American Association for the Surgery of Trauma multi-institutional trial.

BACKGROUND: The optimal time to initiate venous thromboembolism (VTE) chemoprophylaxis (VTEp) after blunt solid organ injury remains controversial, as VTE mitigation must be balanced against bleeding promulgation. Evidence from primarily small, retrospective, single-center work suggests that VTEp ≤48 hours is safe and effective. This study was undertaken to validate this clinical practice. METHODS: Blunt trauma patients presenting to 19 participating trauma centers in North America were screened over a 1-year study period beginning between August 1 and October 1, 2021. Inclusions were age older than 15 years; ≥1 liver, spleen, or kidney injury; and initial nonoperative management. Exclusions were transfers, emergency department death, pregnancy, and concomitant bleeding disorder/anticoagulation/antiplatelet medication. A priori power calculation stipulated the need for 1,158 patients. Time of VTEp initiation defined study groups: Early (≤48 hours of admission) versus Late (>48 hours). Bivariate and multivariable analyses compared outcomes. RESULTS: In total, 1,173 patients satisfied the study criteria with 571 liver (49%), 557 spleen (47%), and 277 kidney injuries (24%). The median patient age was 34 years (interquartile range, 25-49 years), and 67% (n = 780) were male. The median Injury Severity Score was 22 (interquartile range, 14-29) with Abbreviated Injury Scale Abdomen score of 3 (interquartile range, 2-3), and the median American Association for the Surgery of Trauma grade of solid organ injury was 2 (interquartile range, 2-3). Early VTEp patients (n = 838 [74%]) had significantly lower rates of VTE (n = 28 [3%] vs. n = 21 [7%], p = 0.008), comparable rates of nonoperative management failure (n = 21 [3%] vs. n = 12 [4%], p = 0.228), and lower rates of post-VTEp blood transfusion (n = 145 [17%] vs. n = 71 [23%], p = 0.024) when compared with Late VTEp patients (n = 301 [26%]). Late VTEp was independently associated with VTE (odd ratio, 2.251; p = 0.046). CONCLUSION: Early initiation of VTEp was associated with significantly reduced rates of VTE with no increase in bleeding complications. Venous thromboembolism chemoprophylaxis initiation ≤48 hours is therefore safe and effective and should be the standard of care for patients with blunt solid organ injury. LEVEL OF EVIDENCE: Therapeutic and Care Management; Level III.

Empiric Cryoprecipitate Transfusion in Patients with Severe Hemorrhage: Results from the US Experience in the International CRYOSTAT-2 Trial.

BACKGROUND: Hypofibrinogenemia has been shown to predict massive transfusion and is associated with higher mortality in severely injured patients. However, the role of empiric fibrinogen replacement in bleeding trauma patients remains controversial. We sought to determine the effect of empiric cryoprecipitate as an adjunct to a balanced transfusion strategy (1:1:1). STUDY DESIGN: This study is a subanalysis of patients treated at the single US trauma center in a multicenter randomized controlled trial. Trauma patients (more than 15 years) were eligible if they had evidence of active hemorrhage requiring emergent surgery or interventional radiology, massive transfusion protocol (MTP) activation, and received at least 1 unit of blood. Transfer patients, those with injuries incompatible with life, or those injured more than 3 hours earlier were excluded. Patients were randomized to standard MTP (STANDARD) or MTP plus 3 pools of cryoprecipitate (CRYO). Primary outcomes included all-cause mortality at 28 days. Secondary outcomes were transfusion requirements, intraoperative and postoperative coagulation laboratory values, and quality-of-life measures (Glasgow outcome score-extended). RESULTS: Forty-nine patients (23 in the CRYO group and 26 in the STANDARD group) were enrolled between May 2021 and October 2021. Time to randomization was similar between groups (14 vs 24 minutes, p = 0.676). Median time to cryoprecipitate was 41 minutes (interquartile range 37 to 48). There were no differences in demographics, arrival physiology, laboratory values, or injury severity. Intraoperative and ICU thrombelastography values, including functional fibrinogen, were similar between groups. There was no benefit to CRYO with respect to post-emergency department transfusions (intraoperative and ICU through 24 hours), complications, Glasgow outcome score, or mortality. CONCLUSIONS: In this study of severely injured, bleeding trauma patients, empiric cryoprecipitate did not improve survival or reduce transfusion requirements. Cryoprecipitate should continue as an "on-demand" addition to a balanced transfusion strategy, guided by laboratory values and should not be given empirically.

Hypofibrinogenemia following injury in 186 children and adolescents: identification of the phenotype, current outcomes, and potential for intervention.

Objectives: Recent studies evaluating fibrinogen replacement in trauma, along with newly available fibrinogen-based products, has led to an increase in debate on where products such as cryoprecipitate belong in our resuscitation strategies. We set out to define the phenotype and outcomes of those with hypofibrinogenemia and evaluate whether fibrinogen replacement should have a role in the initial administration of massive transfusion. Methods: All patients <18 years of age presenting to our trauma center 11/17-4/21 were reviewed. We then evaluated all patients who received emergency-release and massive transfusion protocol (MTP) products. Patients were defined as hypofibrinogenemic (HYPOFIB) if admission fibrinogen <150 or rapid thrombelastography (r-TEG) angle <60 degrees. Our analysis sought to define risk factors for presenting with HYPOFIB, the impact on outcomes, and whether early replacement improved mortality. Results: 4169 patients were entered into the trauma registry, with 926 level 1 trauma activations, of which 186 patients received emergency-release blood products during this time; 1%, 3%, and 10% were HYPOFIB, respectively. Of the 186 patients of interest, 18 were HYPOFIB and 168 were non-HYPOFIB. The HYPOFIB patients were significantly younger, had lower field and arrival Glasgow Coma Scale, had higher head Abbreviated Injury Scale, arrived with worse global coagulopathy, and died from brain injury. Non-HYPOFIB patients were more likely to have (+)focused assessment for the sonography of trauma on arrival, sustained severe abdominal injuries, and die from hemorrhage. 12% of patients who received early cryoprecipitate (0-2 hours) had higher mortality by univariate analysis (55% vs 31%, p=0.045), but no difference on multivariate analysis (OR 0.36, 95% CI 0.07 to 1.81, p=0.221). Those receiving early cryoprecipitate who survived after pediatric intensive care unit (PICU) admission had lower PICU fibrinogen and r-TEG alpha-angle values. Conclusion: In pediatric trauma, patients with hypofibrinogenemia on admission are most likely younger and to have sustained severe brain injury, with an associated mortality of over 80%. Given the absence of bleeding-related deaths in HYPOFIB patients, this study does not provide evidence for the empiric use of cryoprecipitate in the initial administration of a massive transfusion protocol. Level of Evidence: Level III - Therapeutic/Care Management.

The reports of my death are greatly exaggerated: An evaluation of futility cut points in massive transfusion.

BACKGROUND: Following COVID and the subsequent blood shortage, several investigators evaluated futility cut points in massive transfusion. We hypothesized that early aggressive use of damage-control resuscitation, including whole blood (WB), would demonstrate that these cut points of futility were significantly underestimating potential survival among patients receiving >50 U of blood in the first 4 hours. METHODS: Adult trauma patients admitted from November 2017 to October 2021 who received emergency-release blood products in prehospital or emergency department setting were included. Deaths within 30 minutes of arrival were excluded. Total blood products were defined as total red blood cell, plasma, and WB in the field and in the first 4 hours after arrival. Patients were first divided into those receiving ≤50 or >50 U of blood in the first 4 hours. We then evaluated patients by whether they received any WB or received only component therapy. Thirty-day survival was evaluated for all included patients. RESULTS: A total of 2,299 patients met the inclusion criteria (2,043 in ≤50 U, 256 in >50 U groups). While there were no differences in age or sex, the >50 U group was more likely to sustain penetrating injury (47% vs. 30%, p < 0.05). Patients receiving >50 U of blood had lower field and arrival blood pressure and larger prehospital and emergency department resuscitation volumes ( p < 0.05). Patients in the >50 U group had lower survival than those in the ≤50 cohort (31% vs. 79%; p < 0.05). Patients who received WB (n = 1,291) had 43% increased odds of survival compared with those who received only component therapy (n = 1,008) (1.09-1.87, p = 0.009) and higher 30-day survival at transfusion volumes >50 U. CONCLUSION: Patient survival rates in patients receiving >50 U of blood in the first 4 hours of care are as high as 50% to 60%, with survival still at 15% to 25% after 100 U. While responsible blood stewardship is critical, futility should not be declared based on high transfusion volumes alone. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level III.

Power of mentorship for civilian and military acute care surgeons: identifying and leveraging opportunities for longitudinal professional development.

Across disciplines, mentorship has been recognized as a key to success. Acute care surgeons, focused on the care of trauma surgery, emergency general surgery and surgical critical care, practice in a wide variety of settings and have unique mentorship needs across all phases of their career. Recognizing the need for robust mentorship and professional development, the American Association for the Surgery of Trauma (AAST) convened an expert panel entitled 'The Power of Mentorship' at the 81st annual meeting in September 2022 (Chicago, Illinois). This was a collaboration between the AAST Associate Member Council (consisting of surgical resident, fellow and junior faculty members), the AAST Military Liaison Committee, and the AAST Healthcare Economics Committee. Led by two moderators, the panel consisted of five real-life mentor-mentee pairs. They addressed the following realms of mentorship: clinical, research, executive leadership and career development, mentorship through professional societies, and mentorship for military-trained surgeons. Recommendations, as well as pearls and pitfalls, are summarized below.

Is the use of nonsteroidal anti-inflammatories after bowel anastomosis in trauma safe?

BACKGROUND: With an increasing interest in multimodal and opioid-reducing pain strategies, nonsteroidal anti-inflammatory drugs (NSAIDs) have become common place in the care of injured patients. Long-standing concerns of increased anastomotic leak (AL) rate with the use of NSAIDs, however, have persisted. We hypothesized that there would be no significant risk associated with NSAID use after bowel anastomosis in trauma patients. METHODS: All patients presenting to a level 1 trauma center who required intestinal resection and anastomosis from 2011 to 2017 were reviewed. Patients receiving NSAIDs were compared with those managed without NSAIDs. Primary outcome of interest was anastomosis-related complications (AL, intra-abdominal abscess, anastomotic bleed, fascial dehiscence, fascial dehiscence, and enterocutaneous fistula). Multivariable logistic regression analyses were performed with propensity adjustment for inverse probability of NSAID treatment weights. RESULTS: A total of 295 patients met the inclusion criteria with 192 receiving NSAIDs. Patients receiving NSAIDs had lower abdominal Abbreviated Injury Scale and Injury Severity Score ( p < 0.046). Arrival systolic blood pressure, diastolic blood pressure, and Glasgow Coma Scale were higher in the NSAID group ( p < 0.013). After propensity weighting, NSAID use was not a major predictor of anastomotic complication ( p = 0.39). There was an increased risk of AL with perioperative vasopressor exposure (odds ratio [OR], 3.33; 95% confidence interval [CI], 1.17-9.05; p < 0.001). Increasing red blood cell transfusions in the first 24 hours were associated with intra-abdominal complications (OR, 1.02; 95% CI, 1.00-1.04; p = 0.05). Nonsteroidal anti-inflammatory drug exposure demonstrated a weak association with AL (OR, 1.92; 95% CI, 0.97-3.90; p = 0.06). CONCLUSION: Consistent with previous studies, perioperative vasopressor exposure and increased number of red blood cell transfusions are risk factors for ALs and intra-abdominal complications, respectively. Nonsteroidal anti-inflammatory drug use in trauma patients with multiple risk factors may be associated with an increased risk of AL and should be used with caution in the setting of other established risk factors. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level III.

Perforated Appendicitis: An Unintended Consequence During the Coronavirus-19 Pandemic.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has had major clinical impact across the globe. Delayed presentation for medical emergencies has been noted by the medical community. There has been limited reporting on the impact for the care for emergent surgical conditions. We sought to describe the effect of the global pandemic on the presentation and outcomes for the most common urgent general surgery disease process, acute appendicitis. METHODS: We performed a retrospective review of patients admitted to the United States Naval Hospital Okinawa during the COVID-19 pandemic, from January 2020 to May 2020 (COVID cohort), and compared them to a historical cohort (pre-COVID cohort) over the prior 2 years. Demographics, clinical presentation data, and interventions were collected. RESULTS: Of the 80 patients with appendicitis, 20% presented perforated. Most patients were male (71%), presented with 1 day of symptoms and had a length of stay of 1 to 2 days. Comparing groups, 13% of the pre-COVID group vs. 31% of the COVID cohort presented perforated (P = .04), with a symptom duration of 1.6 vs. 2.7 days before presentation (P = .075), respectively. CONCLUSIONS: The COVID-19 pandemic and the global systematic response has impacted unrelated medical and surgical conditions. At our overseas military hospital with minimal disease burden, we observed a delay in presentation for acute appendicitis with a higher incidence of perforation. Patients should be empowered to continue to seek care for urgent and emergent medical and surgical conditions so that they are not harmed by fear of COVID-19 rather than by COVID-19 itself.

Nationwide analysis of resuscitative thoracotomy in pediatric trauma: Time to differentiate from adult guidelines?

BACKGROUND: Emergency department thoracotomy (EDT) for pediatric patients is uncommon, and practice patterns have not been evaluated. We examined the indications and outcomes for EDT by trauma center designation using a nationwide database. METHODS: Patients 16 years or younger who underwent EDT within 30 minutes of arrival from 2013 to 2016 were identified in the American College of Surgeons National Trauma Data Bank. Patient demographic information, indications for EDT, and outcomes were analyzed. Outcomes were compared between centers with and without pediatric trauma center designation. RESULTS: A total of 114 patients were identified for analysis with a mean ± SD age of 10.3 ± 4.7 years. Patients were predominantly male (69%) with a median Injury Severity Score of 26 (interquartile range, 18-42). Penetrating trauma occurred in 56%. Overall, mortality was 90% and was similar in penetrating and blunt trauma (88% vs. 94%; p = 0.34). There were no survivors among the 53 patients (46%) who arrived with no signs of life. Among the 11 patients (10%) who survived, median length of stay was 26 days (interquartile range, 6-28 days). Overall, 8% of EDT was performed at free-standing pediatric trauma centers, 45% at adult centers, and 47% at combined trauma centers. Mortality rates and indications were similar among trauma centers regardless of designation status. CONCLUSION: In a national population-based data set, the mortality after pediatric EDT is high, and many of these procedures are performed at nonpediatric trauma centers. Regardless of injury mechanism, EDT is not appropriate in children without signs of life on arrival. Pediatric guidelines are needed to increase awareness of the poor outcomes and limited indications for EDT. LEVEL OF EVIDENCE: Therapeutic, level IV.

Pediatric extremity vascular trauma: It matters where it is treated.

BACKGROUND: Extremity vascular injuries in children are rare events that present unique therapeutic challenges. The absence of a pediatric-specific protocol for definitive care of these injuries risks variability in treatment practices and outcomes. Using a nationwide data set, we investigated variations in the management and outcomes of pediatric patients with peripheral vascular trauma and characterized differences based on hospital category. METHODS: Retrospective cohort study using the American College of Surgeons (ACS) National Trauma Data Bank to identify patients 16 years or younger with extremity vascular trauma admitted in calendar year 2016. Hospitals were categorized as ACS-verified pediatric trauma centers (Level I or II), ACS-verified adult trauma centers (Level I or II), or other hospitals (all other trauma centers and nondesignated hospitals). Patient data were evaluated by hospital category. RESULTS: Among 164,882 pediatric admissions, 702 patients were identified for analysis. There were 430 (61.3%) patients with upper-extremity injuries, 270 (38.5%) with lower-extremity injuries, and 2 (0.2%) had both. Mean age was 11.5 years, and 51.6% were blunt-injured. Overall, 40.2% were admitted to pediatric trauma centers, 28.9% to adult trauma centers, and 30.9% to other hospitals. Hospitals without ACS trauma center verification had a significantly higher amputation rate than any ACS-verified adult or pediatric center (p = 0.013). CONCLUSION: The incidence of pediatric extremity vascular injury is low. Hospitals with ACS trauma center verification have greater pediatric limb salvage rates than those without verification. Future study should seek to identify specific regional or resource-related factors that contribute to this disparity. LEVEL OF EVIDENCE: Epidemiological, level III.

Evaluating surgical outcomes in pediatric extremity vascular trauma.

BACKGROUND: The purpose of this study was to evaluate the epidemiology and management of pediatric vascular extremity trauma to assess injury patterns and other factors that may contribute to poor outcomes. METHODS: Using the California Office of Statewide Health Planning and Development discharge database, we identified pediatric patients with extremity arterial trauma admitted to acute-care hospitals from 2007 to 2014. Demographics, management patterns, and outcomes were collected and analyzed. RESULTS: A total of 775 patients were treated for an extremity arterial injury. Overall, 40% were admitted to pediatric trauma centers and 39% to adult trauma centers. Management was predominantly by open surgical repair. Injury to the common femoral artery was associated with mortality (Hazard Ratio 3.9; 95% CI 1.1-14.5; p < 0.05). Popliteal artery injuries (Odds Ratio [OR] 4.8; 95% CI 1.2-19.9; p < 0.05) and anterior tibial artery injuries (OR 7.1; 95% CI 1.4-37.3; p < 0.05) had an increased risk of amputation. There was no difference in amputation or mortality rates by hospital category. CONCLUSIONS: Pediatric extremity arterial injuries are rare. In California, outcomes are similar by hospital type. Common femoral artery injuries are associated with an increased risk of mortality, while popliteal and anterior tibial artery injuries are associated with an increased risk of amputation. TYPE OF STUDY: Prognosis Study. LEVEL OF EVIDENCE: Level III.

The Initial Impact of Tele-Critical Care on the Surgical Services of a Community Military Hospital.

Introduction: Mortality is reduced in hospitals staffed with intensivists, however, many smaller military hospitals lack intensivist support. Naval Hospital Camp Pendleton (NHCP) is a Military Treatment Facility (MTF) that operates a 6-bed Intensive Care Unit (ICU) north of its referral center, Naval Medical Center San Diego (NMCSD). To address a gap in NHCP on-site intensivist coverage, a comprehensive Tele-Critical Care (TCC) support system was established between NHCP and NMCSD. To examine the initial impact of telemedicine on surgical ICU patients, we compare NHCP surgical ICU admissions before and after TCC implementation. Materials and methods: Patient care by remote intensivist was achieved utilizing video teleconferencing technology, and remote access to electronic medical records. Standardization was promoted by adopting protocols and mandatory intensivist involvement in all ICU admissions. Surgical ICU admissions prior to TCC implementation (pre-TCC) were compared to those following TCC implementation (post-TCC). Results: Of 828 ICU admissions, 21% were surgical. TCC provided coverage during 35% of the intervention period. Comparing pre-TCC and post-TCC periods, there was a significant increase in the percentage of surgical ICU admissions [15.3 % vs 24.6%, p = 0.01] and the average monthly APACHE II score [4.1vs 6.5, p = 0.03]. The total number of surgical admissions per month also increased [3.9 vs 6.3, p = 0.009]. No adverse outcomes were identified. Conclusion: Implementation of TCC was associated with an increase in the scope and complexity of surgical admissions with no adverse outcomes. Surgeons were able to safely expand the surgical services offered requiring perioperative ICU care to patients who previously may have been transferred. Caring for these types of patients not only maintains the operational readiness of deployable caregivers but patient experience is also enhanced by minimizing transfers away from family. Further exploration of TCC on surgical case volume and complexity is warranted.

Risk factors for deep vein thrombosis and pulmonary embolism after traumatic injury: A competing risks analysis.

BACKGROUND: Venous thromboembolism, including deep vein thrombosis (DVT) and pulmonary embolism (PE), is typically reported as a composite measure of the quality of trauma center care. Given that recent data suggesting postinjury DVT and PE are distinct clinical processes, a better understanding may result from analyzing them as independent, competing events. Using competing risks analysis, we evaluated our hypothesis that the risk factors and timing of postinjury DVT and PE are different. METHODS: We examined all adult trauma patients admitted to our Level I trauma center from July 2006 to December 2011 who received at least one surveillance duplex ultrasound of the lower extremities and who were at high risk or greater for DVT. Outcomes included DVT and PE events, and time-to-event from admission. We used competing risks analysis to evaluate risk factors for DVT while accounting for PE as a competing event, and vice versa. RESULTS: Of 2,370 patients, 265 (11.2%) had at least one venous thromboembolism event, 235 DVT only, 19 PE only, 11 DVT and PE. Within 2 days of admission, 38% of DVT cases had occurred compared with 26% of PE. Competing risks modeling of DVT as primary event identified older age, severe injury (Injury Severity Score, ≥ 15), mechanical ventilation longer than 4 days, active cancer, history of DVT or PE, major venous repair, male sex, and prophylactic enoxaparin and prophylactic heparin as associated risk factors. Modeling of PE as the primary event showed younger age, nonsevere injury (Injury Severity Score, < 15), central line placement, and prophylactic heparin as relevant factors. CONCLUSION: The risk factors for PE and DVT after injury were different, suggesting that they are clinically distinct events that merit independent consideration. Many DVT events occurred early despite prophylaxis, bringing into question the preventability of postinjury DVT. We recommend trauma center quality reporting program measures be revised to account for DVT and PE as unique events. LEVEL OF EVIDENCE: Epidemiologic, level III.

Determining the magnitude of surveillance bias in the assessment of lower extremity deep venous thrombosis: A prospective observational study of two centers.

BACKGROUND: Venous thromboembolism (VTE) remains a significant cause of morbidity and mortality in trauma. Controversy exists regarding the use of lower extremity duplex ultrasound screening and surveillance (LEDUS). Advocates cite earlier diagnosis and treatment of deep venous thrombosis (DVT) to prevent clot propagation and pulmonary embolism (PE). Opponents argue that LEDUS identifies more DVT (surveillance bias) but does not reduce the incidence of PE. We sought to determine the magnitude of surveillance bias associated with LEDUS and test the hypothesis that LEDUS does not decrease the incidence of PE after injury. METHODS: We compared data from two Level 1 trauma centers: Scripps Mercy Hospital, which used serial LEDUS, and Christiana Care Health System, which used LEDUS only for symptomatic patients. Beginning in 2013, both centers prospectively collected data on demographics, injury severity, and VTE risk for patients admitted for more than 48 hours. Both centers used mechanical and pharmacologic prophylaxis based on VTE risk assessment. RESULTS: Scripps Mercy treated 772 patients and Christiana Care treated 454 patients with similar injury severity and VTE risk. The incidence of PE was 0.4% at both centers. The odds of a DVT diagnosis were 5.3 times higher (odds ratio, 5.3; 95% confidence interval, 2.5-12.9; p < 0.0001) for patients admitted to Scripps Mercy than for patients admitted to Christiana Care. Of the 80 patients who developed DVT, PE, or both, 99% received prophylaxis before the event. Among those who received pharmacologic prophylaxis, the VTE rates between the two centers were not statistically significantly different (Scripps Mercy, 11% vs. Christiana Care, 3%; p = 0.06). CONCLUSION: The odds of a diagnosis of DVT are increased significantly when a program of LEDUS is used in trauma patients. Neither pharmacologic prophylaxis nor mechanical prophylaxis is completely effective in preventing VTE in trauma patients. VTE should not be considered a "never event" in this cohort. LEVEL OF EVIDENCE: Prognostic/epidemiologic study, level III; therapeutic study, level III.

Heparin versus enoxaparin for prevention of venous thromboembolism after trauma: A randomized noninferiority trial.

BACKGROUND: Research comparing enoxaparin with unfractionated heparin (UFH) given every 12 hours for venous thromboembolism (VTE) prophylaxis after trauma overlooks original recommendations that UFH be given every 8 hours. We conducted a prospective, randomized, noninferiority trial comparing UFH every 8 hours and standard enoxaparin every 12 hours. We hypothesized that the incidence of VTE in trauma patients receiving UFH every 8 hours would be no more than 10% higher than that in patients receiving enoxaparin every 12 hours. METHODS: Trauma patients who met criteria for VTE prophylaxis at a Level I trauma center were randomly assigned to 5,000-U UFH every 8 hours or 30-mg enoxaparin every 12 hours between November 2012 and September 2014. Surveillance duplex ultrasound was performed twice weekly on intensive care unit patients and weekly on ward patients. Primary end points were deep vein thrombosis diagnosed by duplex ultrasound and pulmonary embolism diagnosed by computed tomography angiography. RESULTS: Of 495 randomized patients, 220 received UFH and 216 received enoxaparin for analysis. Overall, 105 in the UFH group and 103 in the enoxaparin group underwent VTE surveillance or diagnostic testing. In the analysis of randomized patients who received treatment, UFH was noninferior compared with enoxaparin (absolute VTE risk difference, 3.1%; 95% confidence interval, -1.6% to 7.7%; p = 0.196); however, in the screening ultrasound group, the noninferiority of UFH was inconclusive (absolute VTE risk difference, 6.5%; 95% confidence interval, -2.9% to 15.8%; p = 0.179). The two treatments did not differ with regard to adverse events. The pharmaceutical cost for the regimen of UFH ($2,809) was nearly 20-fold lower than that for enoxaparin ($54,138). CONCLUSION: A regimen of UFH every 8 hours may be noninferior to enoxaparin every 12 hours for the prevention of VTE following trauma. Given UFH's cost advantage, the use of UFH for VTE prophylaxis may offer greater value. LEVEL OF EVIDENCE: Therapeutic/care management study, level II.

Venous thromboembolic risk assessment models should not solely guide prophylaxis and surveillance in trauma patients.

BACKGROUND: Venous thromboembolism (VTE) risk assessment models exist to stratify patients at risk for VTE and guide surveillance and prophylaxis. We evaluated the only two models developed specifically for trauma patients: the Trauma Embolic Scoring System (TESS) and the Risk Assessment Profile (RAP). METHODS: Clinical and demographic data on patients admitted from July 2006 to December 2011 who underwent surveillance lower extremity duplex ultrasound were recorded. Patients were excluded if they were missing one or more of the variables required to calculate either TESS or RAP. Patients received prophylaxis according to American College of Chest Physicians guidelines. TESS and RAP scores were calculated retrospectively and compared between patients with VTE and patients without VTE. High risk was defined by the models as TESS score of 7 or greater and RAP score of 5 or greater. RESULTS: A total of 2,868 patients received surveillance lower extremity duplex ultrasound. TESS score was calculated for 2,140 patients; 215 developed VTE, 110 (51%) of whom had TESS score less than 7. The sensitivity and specificity at a cutoff point of 7 were 49% and 72%, respectively. RAP score was calculated for 1,505 patients; 152 developed VTE, 26 (17%) of whom had RAP score of less than 5. The sensitivity and specificity at a cutoff point of 5 were 83% and 37%, respectively. The area under the receiver operating characteristic curve for each model was 0.66. CONCLUSION: A clinically significant number of patients who developed VTE were classified as low risk by both TESS and RAP. The indications for VTE surveillance and chemoprophylaxis should not be based exclusively on these scores. These results suggest that additional variables should be sought to improve risk assessment for VTE following trauma. LEVEL OF EVIDENCE: Care management study, level III.

Does resuscitation with plasma increase the risk of venous thromboembolism?

BACKGROUND: Resuscitation with blood products improves survival in patients with traumatic hemorrhage. However, the risk of venous thromboembolic (VTE) complications associated with fresh frozen plasma (FFP) resuscitation is unknown. We hypothesized that a higher ratio of FFP to packed red blood cells (PRBCs) given during acute resuscitation increases the risk of VTE independent of severity of injury and shock. METHODS: The records of patients admitted from April 2007 to December 2011 who had surveillance lower extremity duplex ultrasounds were retrospectively reviewed. Patients who received at least 1 U of PRBCs within 24 hours of admission were included. Patients who died without VTE were excluded. The relationship between FFP and VTE was evaluated using logistic regression. RESULTS: A total of 381 patients met inclusion criteria, of whom 77 (20.2%) developed VTE. In patients who required less than 4 U of PRBCs, increasing units of FFP were associated with an increasing risk for VTE, with each unit of FFP having an adjusted odds ratio of 1.27 (95% confidence interval, 1.04-1.54, p = 0.015). Conversely, in patients who required four or greater units of PRBCs, FFP in equal or greater ratios than PRBCs was not associated with VTE. CONCLUSION: Each unit of FFP increased VTE risk by 25% in patients who required less than 4 U of PRBCs. In patients who required 4 U or greater PRBCs, FFP administration conferred no increased risk of VTE. This suggests that FFP should be used cautiously when early hemodynamic stability can be achieved with less than 4 U of PRBCs. LEVEL OF EVIDENCE: Care management study, level III.

Below-knee deep vein thrombosis: an opportunity to prevent pulmonary embolism?

BACKGROUND: The prevention of venous thromboembolic disease following trauma is a priority. In contrast to above-knee deep vein thrombosis (AKDVT), the management of below-knee deep vein thrombosis (BKDVT) is controversial because the risk of pulmonary embolism (PE) has not been firmly established. We hypothesized that BKDVT and AKDVT have an equivalent risk for PE in trauma patients. METHODS: We identified patients from July 2006 to December 2011 with BKDVT and/or AKDVT diagnosed by lower extremity duplex ultrasound (LEDU) and patients with PE diagnosed by computed tomography angiogram. Time of DVT onset, progression or regression, and time of PE were assessed. The BKDVT and AKDVT patient groups were defined by the location of DVT on initial LEDU. The use of therapeutic anticoagulation and inferior vena cava filter (IVCF) were compared between the BKDVT and AKDVT groups. RESULTS: Of 11,330 patients evaluated during the study period, 2,881 (25.4%) underwent surveillance LEDU, and 251 (8.7%) of these patients had DVT alone or associated with PE. BKDVT progressed to AKDVT and/or PE in 21 patients (12.9%). PE rates were 6.1% and 1.1% in the BKDVT and AKDVT groups, respectively (p = 0.1). There was a higher rate of therapeutic anticoagulation and/or IVCF in the AKDVT group than in the BKDVT group (86% vs. 24%, p < 0.0001). CONCLUSION: In our study population, BKDVT was associated with a higher rate of PE compared with AKDVT, which was likely secondary to the treatment of AKDVT. Because BKDVT progressed to AKDVT or PE in 1 of 8 patients, BKDVT should not be ignored in trauma patients. Aggressive chemical prophylaxis and perhaps therapeutic anticoagulation or IVCF should be considered in patients with BKDVT. Further investigation is warranted to confirm these conclusions. LEVEL OF EVIDENCE: Therapeutic study, level IV.

Isolated traumatic brain injury and venous thromboembolism.

BACKGROUND: Traumatic brain injury (TBI) is considered an independent risk factor of venous thromboembolism (VTE). However, the role of TBI severity in VTE risk has not been determined. We hypothesized that increased severity of brain injury in patients with isolated TBI (iTBI) is associated with an increased incidence of VTE. METHODS: The records of patients admitted from June 2006 to December 2011 were reviewed for injury data, VTE risk factors, results of lower extremity surveillance ultrasound, and severity of TBI. Patients were identified by DRG International Classification of Diseases-9th Rev. codes for TBI, and only those with a nonhead Abbreviated Injury Scale (AIS) score of 1 or lower, indicating minimal associated injury, were included. The association of iTBI and VTE was determined using a case-control design. Among iTBI patients, those diagnosed with VTE (cases) were matched for age, sex, and admission year to those without VTE (controls). Data were analyzed using conditional logistic regression. RESULTS: There were 345 iTBI patients: 41 cases (12%) and 304 controls (88%). A total of 151 controls could not be matched to an appropriate case and were excluded. Of the remaining 153 controls, 1 to 16 controls were matched to each of the 41 VTE cases. Compared with the controls, the cases had a higher mean head-AIS score (4.4 vs. 3.9, p = 0.001) and overall Injury Severity Score (20.4 vs. 16.8, p = 0.001). Following adjustment for all factors found to be associated with VTE (ventilator days, central line placement, operative time > 2 hours, chemoprophylaxis, history of VTE, and history of cancer), the cases were significantly more likely to have a greater head injury severity (head-AIS score ≥ 5; odds ratio, 5.25; 95% confidence interval, 1.59-17.30; p = 0.006). CONCLUSION: The incidence of VTE in iTBI patients was significantly associated with the severity of TBI. VTE surveillance protocols may be warranted in these high-risk patients, as early detection of VTE could guide subsequent therapy. LEVEL OF EVIDENCE: Epidemiologic/prognostic study, level III.