Fibrinolytic Activation in Patients with Progressive Intracranial Hemorrhage after Traumatic Brain Injury.

Progression of intracranial hemorrhage (PICH) is a significant cause of secondary brain injury in patients with traumatic brain injury (TBI). Previous studies have implicated a variety of mediators that contribute to PICH. We hypothesized that patients with PICH would display either a hypocoagulable state, hyperfibrinolysis, or both. We conducted a prospective study of adult trauma patients with isolated TBI. Blood was obtained for routine coagulation assays, platelet count, fibrinogen, thrombelastography, markers of thrombin generation, and markers of fibrinolysis at admission and 6, 12, 24, and 48 h. Univariate analyses were performed to compare baseline characteristics between groups. Linear regression models were created, adjusting for baseline differences, to determine the relationship between individual assays and PICH. One hundred forty-one patients met entry criteria, of whom 71 had hemorrhage progression. Patients with PICH had a higher Injury Severity Score and Abbreviated Injury Scale score (head), a lower Glasgow Coma Scale score, and lower plasma sodium on admission. Patients with PICH had higher D-dimers on admission. After adjusting for baseline differences, elevated D-dimers remained significantly associated with PICH compared to patients without PICH at admission. Hypocoagulation was not significantly associated with PICH in these patients. The association between PICH and elevated D-dimers early after injury suggests that fibrinolytic activation may contribute to PICH in patients with TBI.

Splenectomy is associated with higher infection and pneumonia rates among trauma laparotomy patients.

Splenectomy increases lifetime risk of thromboembolism (VTE) and is associated with long-term infectious complications, primarily, overwhelming post-splenectomy infection (OPSI). Our objective was to evaluate risk of VTE and infection at index hospitalization post-splenectomy. Retrospective review of all patients who received a laparotomy in the NTDB. Propensity score matching for splenectomy was performed, based on ISS, abdominal abbreviated injury score >3, GCS, sex and mechanism. Major complications, VTE, and infection rates were compared. Multiple logistic regression models were utilized to evaluate splenectomy-associated complications. 93,221 laparotomies were performed and 17% underwent splenectomy. Multiple logistic regression models did not demonstrate an association between splenectomy and major complications (OR 0.96, 95% CI 0.91-1.03, p = 0.25) or VTE (OR 1.05, 95% CI 0.96-1.14, p = 0.33). Splenectomy was independently associated with infection (OR 1.07, 95% CI 1.00-1.14, p = 0.045). Subgroup analysis of patients with infection demonstrated that splenectomy was most strongly associated with pneumonia (OR 1.41, 95% CI 1.26-1.57, p < 0.001). Splenectomy is not associated with higher overall complication or VTE rates during index hospitalization. However, splenectomy is associated with a higher rate of pneumonia.

Onset of Coagulation Function Recovery Is Delayed in Severely Injured Trauma Patients with Venous Thromboembolism.

BACKGROUND: Altered coagulation function after trauma can contribute to development of venous thromboembolism (VTE). Severe trauma impairs coagulation function, but the trajectory for recovery is not known. We hypothesized that enhanced, early recovery of coagulation function increases VTE risk in severely injured trauma patients. STUDY DESIGN: Secondary analysis was performed on data from the Pragmatic Randomized Optimal Platelet and Plasma Ratio (PROPPR) trial, excluding patients who died within 24 hours or were on pre-injury anticoagulants. Patient characteristics, adverse outcomes, and parameters of platelet function and coagulation (thromboelastography) were compared from admission to 72 hours between VTE (n = 83) and non-VTE (n = 475) patients. A p value < 0.05 indicates significance. RESULTS: Despite similar patient demographics, VTE patients exhibited hypercoagulable thromboelastography parameters and enhanced platelet function at admission (p < 0.05). Both groups exhibited hypocoagulable thromboelastography parameters, platelet dysfunction, and suppressed clot lysis (low clot lysis at 30 minutes) 2 hours after admission (p < 0.05). The VTE patients exhibited delayed coagulation recovery (a significant change compared with 2 hours) of K-value (48 vs 24 hours), α-angle (no recovery), maximum amplitude (24 vs 12 hours), and clot lysis at 30 minutes (48 vs 12 hours). Platelet function recovery mediated by arachidonic acid (72 vs 4 hours), ADP (72 vs 12 hours), and collagen (48 vs 12 hours) was delayed in VTE patients. The VTE patients had lower mortality (4% vs 13%; p < 0.05), but fewer hospital-free days (0 days [interquartile range 0 to 8 days] vs 10 days [interquartile range 0 to 20 days]; p < 0.05) and higher complication rates (p < 0.05). CONCLUSIONS: Recovery from platelet dysfunction and coagulopathy after severe trauma were delayed in VTE patients. Suppressed clot lysis and compensatory mechanisms associated with altered coagulation that can potentiate VTE formation require additional investigation.

Thrombelastography-Based Dosing of Enoxaparin for Thromboprophylaxis in Trauma and Surgical Patients: A Randomized Clinical Trial.

Importance: Prophylactic enoxaparin is used to prevent venous thromboembolism (VTE) in surgical and trauma patients. However, VTE remains an important source of morbidity and mortality, potentially exacerbated by antithrombin III or anti-Factor Xa deficiencies and missed enoxaparin doses. Recent data suggest that a difference in reaction time (time to initial fibrin formation) greater than 1 minute between heparinase and standard thrombelastogram (TEG) is associated with a decreased risk of VTE. Objective: To evaluate the effectiveness of TEG-adjusted prophylactic enoxaparin dosing among trauma and surgical patients. Design, Setting, and Participants: This randomized clinical trial, conducted from October 2012 to May 2015, compared standard dosing (30 mg twice daily) with TEG-adjusted enoxaparin dosing (35 mg twice daily) for 185 surgical and trauma patients screened for VTE at 3 level I trauma centers in the United States. Main Outcomes and Measures: The incidence of VTE, bleeding complications, anti-Factor Xa deficiency, and antithrombin III deficiency. Results: Of the 185 trial participants, 89 were randomized to the control group (median age, 44.0 years; 55.1% male) and 96 to the intervention group (median age, 48.5 years; 74.0% male). Patients in the intervention group received a higher median enoxaparin dose than control patients (35 mg vs 30 mg twice daily; P < .001). Anti-Factor Xa levels in intervention patients were not higher than levels in control patients until day 6 (0.4 U/mL vs 0.21 U/mL; P < .001). Only 22 patients (11.9%) achieved a difference in reaction time greater than 1 minute, which was similar between the control and intervention groups (10.4% vs 13.5%; P = .68). The time to enoxaparin initiation was similar between the control and intervention groups (median [range] days, 1.0 [0.0-2.0] vs 1.0 [1.0-2.0]; P = .39), and the number of patients who missed at least 1 dose was also similar (43 [48.3%] vs 54 [56.3%]; P = .30). Rates of VTE (6 [6.7%] vs 6 [6.3%]; P > .99) were similar, but the difference in bleeding complications (5 [5.6%] vs 13 [13.5%]; P = .08) was not statistically significant. Antithrombin III and anti-Factor Xa deficiencies and hypercoagulable TEG parameters, including elevated coagulation index (>3), maximum amplitude (>74 mm), and G value (>12.4 dynes/cm2), were prevalent in both groups. Identified risk factors for VTE included older age (61.0 years vs 46.0 years; P = .04), higher body mass index (calculated as weight in kilograms divided by height in meters squared; 30.6 vs 27.1; P = .03), increased Acute Physiology and Chronic Health Evaluation II score (8.5 vs 7.0; P = .03), and increased percentage of missed doses per patient (14.8% vs 2.5%; P = .05). Conclusions and Relevance: The incidence of VTE was low and similar between groups; however, few patients achieved a difference in reaction time greater than 1 minute. Antithrombin III deficiencies and hypercoagulable TEG parameters were prevalent among patients with VTE. Low VTE incidence may be due to an early time to enoxaparin initiation and an overall healthier and less severely injured study population than previously reported. Trial Registration: clinicaltrials.gov Identifier: NCT00990236.

The Impact of Pre-Hospital Administration of Lactated Ringer's Solution versus Normal Saline in Patients with Traumatic Brain Injury.

Lactated Ringer's (LR) and normal saline (NS) are both used for resuscitation of injured patients. NS has been associated with increased resuscitation volume, blood loss, acidosis, and coagulopathy compared with LR. We sought to determine if pre-hospital LR is associated with improved outcome compared with NS in patients with and without traumatic brain injury (TBI). We included patients receiving pre-hospital LR or NS from the PRospective Observational Multicenter Major Trauma Transfusion (PROMMTT) study. Patients with TBI (Abbreviated Injury Scale [AIS] head ≥3) and without TBI (AIS head ≤2) were compared. Cox proportional hazards models including Injury Severity Score (ISS), AIS head, AIS extremity, age, fluids, intubation status, and hospital site were generated for prediction of mortality. Linear regression models were generated for prediction of red blood cell (RBC) and crystalloid requirement, and admission biochemical/physiological parameters. Seven hundred ninety-one patients received either LR (n = 117) or NS (n = 674). Median ISS, AIS head, AIS extremity, and pre-hospital fluid volume were higher in TBI and non-TBI patients receiving LR compared with NS (p < 0.01). In patients with TBI (n = 308), LR was associated with higher adjusted mortality compared with NS (hazard rate [HR] = 1.78, confidence interval [CI] 1.04-3.04, p = 0.035). In patients without TBI (n = 483), no difference in mortality was demonstrated (HR = 1.49, CI 0.757-2.95, p = 0.247). Fluid type had no effect on admission biochemical or physiological parameters, 6-hour RBC, or crystalloid requirement in either group. LR was associated with increased mortality compared with NS in patients with TBI. These results underscore the need for a prospective randomized trial comparing pre-hospital LR with NS in patients with TBI.

A Disease-Specific Hybrid Rotation Increases Opportunities for Deliberate Practice.

IMPORTANCE: Incorporating deliberate practice (DP) into residency curricula may optimize education. DP includes educationally protected time, continuous expert feedback, and a focus on a limited number of technical skills. It is strongly associated with mastery level learning. OBJECTIVE: Determine if a multidisciplinary breast rotation (MDB) increases DP opportunities. DESIGN: Beginning in 2010, interns completed the 4-week MDB. Three days a week were spent in surgery and surgical clinic. Half-days were in breast radiology, pathology, medical oncology, and didactics. The MDB was retrospectively compared with a traditional community rotation (TCR) and a university surgical oncology service (USOS) using rotation feedback and resident operative volume. Data are presented as mean ± standard deviation. SETTING: Oregon Health and Science University in Portland, Oregon; an academic tertiary care general surgery residency program. PARTICIPANTS: General surgery residents at Oregon Health and Science University participating in either the MDB, TCR or USOS. RESULTS: A total of 31 interns rated the opportunity to perform procedures significantly higher for MDB than TCR or USOS (4.6 ± 0.6 vs 4.2 ± 0.9 and 4.1 ± 1.0, p < 0.05). MDB was rated higher than TCR on quality of faculty teaching and educational materials (4.5 ± 0.7 vs 4.1 ± 0.9 and 4.0 ± 1.2 vs 3.5 ± 1.0, p < 0.05). Interns operated more on the MDB than on the USOS and were more focused on breast resections, lymph node dissections, and port placements than on the traditional surgical rotation or USOS. CONCLUSIONS: The MDB incorporates multidisciplinary care into a unique, disease-specific, and educationally focused rotation. It is highly rated and affords a greater opportunity for DP than either the USOS or TCR. DP is strongly associated with mastery learning and this novel rotation structure could maximize intern education in the era of limited work hours.

Effect of ascorbic acid concentrations on hemodynamics and inflammation following lyophilized plasma transfusion.

BACKGROUND: Compared with lyophilized plasma (LP) buffered with other acids, LP with ascorbic acid (AA) attenuates systemic inflammation and DNA damage in a combat relevant polytrauma swine model. We hypothesize that increasing concentrations of AA in transfused LP will be safe, will be hemodynamically well tolerated, and will attenuate systemic inflammation following polytraumatic injury and hemorrhage in swine. METHODS: This prospective, randomized, blinded study involved 52 female swine. Forty animals were subjected to our validated polytrauma model and resuscitated with LP. Baseline control sham (n = 6), operative control sham (n = 6), low-AA (n = 10), medium-AA (n = 10), high-AA (n = 10) groups, and a hydrochloric acid control (HCL, n = 10) were randomized. Hemodynamics, thrombelastography, and blood chemistries were assessed. Inflammatory cytokines (tumor necrosis factor α, interleukin 6 [IL-6], C-reactive protein, and IL-10) and DNA damage were measured at baseline, 2 hours, and 4 hours after liver injury. Significance was set at p < 0.05, with a Bonferroni correction for multiple comparisons. RESULTS: Hemodynamics, shock, and blood loss were similar between groups. All animals had robust procoagulant activity 2 hours following liver injury. Inflammation was similar between groups at baseline, and AA groups remained similar to HCL following liver injury. IL-6 and tumor necrosis factor α were increased at 2 hours and 4 hours compared with baseline within all groups (p < 0.008). DNA damage increased at 2 hours compared with baseline in all groups (p < 0.017) and further increased at 4 hours compared with baseline in HCL, low-, and high-AA groups (p < 0.005). C-reactive protein was similar between and within groups. IL-10 increased at 2 hours compared with baseline in low- and high-AA groups and remained elevated at 4 hours compared with baseline in the low-AA group (all, p < 0.017). CONCLUSION: Concentrations of AA were well tolerated and did not diminish the procoagulant activity of LP. Within our tested range of concentrations, AA can safely be used to buffer LP.

Traumatic diaphragmatic injury in the American College of Surgeons National Trauma Data Bank: a new examination of a rare diagnosis.

BACKGROUND: Traumatic diaphragmatic injury (TDI) is a rarely diagnosed injury in trauma. Previous studies have been limited in their evaluation of TDI because of small population size and center bias. Although injuries may be suspected based on penetrating mechanism, blunt injuries may be particularly difficult to detect. The American College of Surgeons National Trauma Data Bank is the largest trauma database in the United States. We hypothesized that we could identify specific injury patterns associated with blunt and penetrating TDIs. METHODS: We examined demographics, diagnoses, mechanism of injury, and outcomes for patients with TDI in 2012 as this is the largest and most recent dataset available. Comparisons were made using chi-square or independent samples t test. RESULTS: There were a total of 833,309 encounters in the National Trauma Data Bank in 2012. Three thousand eight hundred seventy-three patients had a TDI (.46%). Of those, 1,240 (33%) patients had a blunt mechanism and 2,543 (67%) had a penetrating mechanism. Patients with blunt TDI were older (44 ± 19 vs 31 ± 13 years, P < .001), had a higher injury severity score (33 ± 14 vs 24 ± 15, P < .001), and a higher mortality rate (19.8% vs 8.8%, P < .001). Compared with patients with penetrating injuries, those with blunt TDI were more likely to have injuries to the thoracic aorta (2.9% vs .5%, P < .001), lung (48.7% vs 28.1, P < .001), bladder (5.9% vs .7%, P < .001), and spleen (44.8% vs 29.1%, P < .001). Penetrating TDI was associated with liver and hollow viscus injuries. CONCLUSIONS: Diaphragmatic injury is an uncommon but significant diagnosis in trauma patients. Blunt injuries may be more likely to be occult; however, a pattern of associated injuries to the aorta, lung, spleen, and bladder should prompt further workup for TDI.

Cirrhosis increases mortality and splenectomy rates following splenic injury.

BACKGROUND: Cirrhosis may be a risk factor for mortality following blunt splenic injury (BSI) and it predicts the need for an operative intervention. METHODS: We performed a case-control study at 3 level 1 trauma centers. Comparisons were made with chi-square test, Wilcoxon rank-sum test, and binary logistic regression, and stratified by propensity for splenectomy. Data are presented as odds ratios (ORs) and 95% confidence intervals (95% CIs). RESULTS: Mortality was 27% (21/77) and cirrhosis was a strong risk factor for death (OR 8.8, 95% CI 3.7 to 21.1). Compared with controls, cirrhosis was an independent risk factor for splenectomy (OR 5.4, 95% CI 2.5 to 11.5), and only splenic injury grade was associated with splenectomy (OR 2.2, 95% CI 1.3 to 3.6). Only admission model for end-stage liver disease was independently associated with mortality after an operation (OR 1.7, 95% CI 1.1 to 2.8). After propensity score matching, we found no association between splenectomy and mortality in cirrhotic patients. CONCLUSION: Cirrhosis dramatically increases mortality and the odds of an operative intervention in BSI patients with pre-existing cirrhosis, and BSI requires vigilant attention and early intervention should be considered.

Moderate elevations in international normalized ratio should not lead to delays in neurosurgical intervention in patients with traumatic brain injury.

BACKGROUND: The management of severe traumatic brain injury (TBI) frequently involves invasive intracranial monitoring or cranial surgery. In our institution, intracranial procedures are often deferred until an international normalized ratio (INR) of less than 1.4 is achieved. There is no evidence that a moderately elevated INR is associated with increased risk of bleeding in patients undergoing neurosurgical intervention (NI). Thrombelastography (TEG) provides a functional assessment of clotting and has been shown to better predict clinically relevant coagulopathy compared with INR. We hypothesized that in patients with TBI, an elevated INR would result in increased time to NI and would not be associated with coagulation abnormalities based on TEG. METHODS: A secondary analysis of prospectively collected data was performed in trauma patients with intracranial hemorrhage that underwent NI (defined as cranial surgery or intracranial pressure monitoring) within 24 hours of arrival. Time from admission to NI was recorded. TEG and routine coagulation assays were obtained at admission. Patients were considered hypocoagulable based on INR if their admission INR was greater than 1.4 (high INR). Manufacturer-specified values were used to determine hypocoagulability for each TEG variable. RESULTS: Sixty-one patients (median head Abbreviated Injury Scale [AIS] score, 5) met entry criteria, of whom 16% had high INR. Demographic, physiologic, and injury scoring data were similar between groups. The median time to NI was longer in patients with high INR (358 minutes vs. 184 minutes, p = 0.027). High-INR patients were transfused more plasma than patients with an INR of 1.4 or less (2 U vs. 0 U, p = 0.01). There was no association between an elevated INR and hypocoagulability based on TEG. CONCLUSION: TBI patients with an admission INR of greater than 1.4 had a longer time to NI. The use of plasma transfusion to decrease the INR may have contributed to this delay. A moderately elevated INR was not associated with coagulation abnormalities based on TEG. Routine plasma transfusion to correct a moderately elevated INR before NI should be reexamined. LEVEL OF EVIDENCE: Diagnostic study, level III.