Differences between blunt and penetrating trauma after resuscitation with hydroxyethyl starch

The purpose of this study was to test the hypothesis that a single bolus of 6% hydroxyethyl starch (HES 450/0.7 in lactated electrolyte injection) during initial resuscitation has a differential effect in blunt and penetrating trauma patients. Consecutive admissions to the trauma service were reviewed. Patients who died within 24 hours were excluded. Multivariate analysis defined individual predictors for the primary outcomes, acute kidney injury (AKI) and mortality within 90 days. Data were expressed as mean ± SD, and significance was assessed at p < 0.05. There were 1,410 patients (76% male; mean ± SD, age 43 ± 18 years; 68% blunt trauma; mean ± SD Injury Severity Score [ISS] 14 ± 11; AKI, 4.4%; and mortality, 3.4%). HES (0.5-1.5 L) was administered to 216 patients (15.3%). After multiple logistic regression, HES remained a significant independent predictor of AKI after blunt trauma (odds ratio [OR], 2.54; 95% confidence interval [CI], 1.24-5.19; area under the receiver operating characteristic curve [AUROC], 0.809) but not penetrating trauma (OR, 0.90; 95% CI, 0.23-3.60; AUROC, 0.849). In separate logistic regression models, HES was a significant predictor of mortality after blunt trauma (OR, 3.77; 95% CI, 0.91-0.97; AUROC, 0.921) but not penetrating trauma (OR, 0.72; 95% CI, 0.13-3.94; AUROC, 0.904). HES is an independent risk factor for AKI and death after blunt, but not penetrating, trauma, which underscores a fundamental difference between these two injury types. Epidemiologic study, level III

Novel prehospital monitor with injury acuity alarm to identify trauma patients who require lifesaving intervention

A miniature wireless vital signs monitor (MWVSM, www.athena.gtx.com) has been designed according to US Special Operations Command specifications for field monitoring of combat casualties. It incorporates an injury acuity algorithm termed the Murphy Factor (MF), which is calculated from whatever vital signs are available at the moment and changes in the last 30 seconds. We tested the hypothesis that MF can identify civilian trauma patients during prehospital transport who will require a lifesaving intervention (LSI) upon hospital admission. From December 2011 to June 2013, a prospective trial was conducted in collaboration with prehospital providers. The MWVSM detects skin temperature, pulse oximetry (SpO2), heart rate (HR), pulse wave transit time, and MF. LSIs included: intubation, tube thoracostomy, central line insertion, blood product transfusion, and operative intervention. Prehospital MWVSM data were compared with simultaneous vital signs (SaO2, systolic blood pressure (SBP), and HR) from a conventional vital signs monitor. Sensitivity, specificity, negative predictive value, positive predictive value, and area under the receiving operating characteristic curves were calculated. Ninety-six trauma patients experienced predominantly blunt trauma (n = 80, 84%), were mostly male (n = 79, 82%), and had a mean ± SD age of 48 ± 19 years and an Injury Severity Score (ISS) of 10 (17). Those who received an LSI (n = 48) had similar demographics but higher ISS (18 vs. 5) and mortality (23% vs. 0%) (all p 100 beats/min, SBP 3 during the entire transport time had the largest area under the receiving operating characteristic curves (0.620, p = 0.081). MF greater than 3 had a specificity of 81%, sensitivity of 39%, positive predictive value of 68%, and negative predictive value of 57% for the need for LSI. A single numeric value has the potential to summarize overall patient status and identify prehospital trauma patients who need an LSI. Prehospital monitoring combined with algorithms that include trends over time could improve prehospital care for both civilian and military trauma. Prospective observational, level II

Hypercoagulability and other risk factors in trauma intensive care unit patients with venous thromboembolism

Thromboelastography (TEG) on hospital admission can identify hypercoagulable trauma patients at risk for venous thromboembolism (VTE), but the value of TEGs obtained after multiple interventions, including tranexamic acid (TXA), has not been defined. We test the following hypotheses. (1) TEG on intensive care unit (ICU) admission can help stratify patients screened with Greenfield's risk assessment profile (RAP) for VTE. (2) TXA is a VTE risk factor, and its effect on fibrinolysis can be identified with TEG. Trauma patients who survived to the ICU with RAP ≥ 10 received serial venous duplex ultrasound examinations and blood samples for coagulation analysis at admission to the ICU and weekly thereafter. Six hundred seventy-eight patients were screened and 121 were enrolled; 76% blunt injury, Injury Severity Score (ISS) 27, 13% mortality. Thromboprophylaxis was administered to 90% of the patients and was started a median of 2 days after hospital admission. VTE was detected in 28% (n = 34) of the patients (27 deep vein thrombosis and 7 pulmonary emboli) and occurred a median 10 days after admission. Twenty-nine percent (n = 10) of VTE occurred within 2 days of admission. Most variables were similar between those with and without VTE, but the VTE group received more operations (3 (2) vs. 2 (2), p = 0.044), had increased ICU days (25 (34) days vs. 15 (18) days, p = 0.004), and was more likely to have abdominal injury with Abbreviated Injury Scale (AIS) score > 2 (59% vs. 39%, p = 0.050). Upon ICU admission, standard coagulation markers were within normal limits, while TEG demonstrated hypercoagulability, but neither was associated with VTE. Repeat TEG one week after admission (n = 58) remained hypercoagulable but transitioned to a different pattern with increased clot strength. TXA was associated with reduced fibrinolysis on initial TEG (p < 0.05) but was not associated with VTE. Trauma ICU patients with RAP ≥ 10 are hypercoagulable at admission to ICU and remain so during recovery. They have a ≥ 25% rate of VTE, despite thromboprophylaxis. TXA is associated with reduced fibrinolysis but does not increase VTE rates. Neither TEG nor standard coagulation markers (measured on ICU admission) stratify high-risk patients who develop VTE from those who do not. Prognostic study, level III

Do all trauma patients benefit from tranexamic acid?

This study tested the hypothesis that early routine use of tranexamic acid (TXA) reduces mortality in a subset of the most critically injured trauma intensive care unit patients. Consecutive trauma patients (n = 1,217) who required emergency surgery (OR) and/or transfusions from August 2009 to January 2013 were reviewed. At surgeon discretion, TXA was administered at a median of 97 minutes (1-g bolus then 1-g over 8 hours) to 150 patients deemed high risk for hemorrhagic death. With the use of propensity scores based on age, sex, traumatic brain injury (TBI), mechanism of injury, systolic blood pressure, transfusion requirements, and Injury Severity Score (ISS), these patients were matched to 150 non-TXA patients. The study population was 43 years old, 86% male, 54% penetrating mechanism of injury, 25% TBI, 28 ISS, with 22% mortality. OR was required in 78% at 86 minutes, transfusion was required in 97% at 36 minutes, and 75% received both. For TXA versus no TXA, more packed red blood cells and total fluid were required, and mortality was 27% versus 17% (all p < 0.05). The effects of TXA were similar in those with or without TBI, although ISS, fluid, and mortality were all higher in the TBI group. Mortality associated with TXA was influenced by the timing of administration (p < 0.05), but any benefit was eliminated in those who required more than 2,000-mL packed red blood cells, who presented with systolic blood pressure of less than 120 mm Hg or who required OR (all p < 0.05). For the highest injury acuity patients, TXA was associated with increased, rather than reduced, mortality, no matter what time it was administered. This lack of benefit can probably be attributed to the rapid availability of fluids and emergency OR at this trauma center. Prospective studies are needed to further identify conditions that may override the benefits from TXA. Therapeutic study, level IV

Does traumatic brain injury increase the risk for venous thromboembolism in polytrauma patients?

Trauma is a major risk factor for venous thromboembolism (VTE). Traumatic brain injury (TBI) is generally considered to further increase the VTE risk, which should prompt routine thromboprophylaxis. However, the associated risk for intracranial hemorrhage often delays anticoagulants. We test the hypothesis that TBI associated with polytrauma results in a higher rate of VTE than polytrauma without TBI. From August 2011 to June 2013, a prospective observational trial with informed consent was performed in 148 intensive care unit (ICU) patients with a Greenfield Risk Assessment Profile score of 10 or greater. Demographics, Greenfield Risk Assessment Profile scores, the incidence of polytrauma, and mortality were similar, but TBI patients had worse Injury Severity Scores (ISS) (32 vs. 22), longer ICU lengths of stay (21 days vs. 12 days), more hypercoagulable thromboelastogram values on admission (94% vs. 79%), more received unfractionated heparin prophylaxis (65% vs. 36%), and the prophylaxis start date was more than a day later (all p < 0.05). Nevertheless, the VTE rate with TBI was similar to that without TBI (25% vs. 26%, p = 0.507). Furthermore, VTE occurred at similar time points after ICU admission with and without TBI. In both groups, about 30% of the VTEs were detected within 2 days of ICU admission and 50% of the VTEs occurred within 10 days of admission despite chemical and mechanical thromboprophylaxis. In complex polytrauma patients who survived to ICU admission and who were prescreened for high VTE risk, TBI did not further increase the risk for VTE. The most likely explanation is that no single risk factor is necessary or sufficient for VTE development, especially in those who routinely receive chemical and mechanical thromboprophylaxis. Epidemiologic study, level III

Vasopressor Use during Emergency Trauma Surgery

Most evidence suggests early vasopressor use is associated with death after trauma, but no previous study has focused on patients requiring emergency operative intervention (OR). We test the hypothesis that vasopressors are harmful in this population. Records from 746 patients requiring OR from July 2009 to March 2013 were retrospectively reviewed and stratified based on vasopressor use (epinephrine [EPI], phenylephrine, ephedrine, norepinephrine, dobutamine, vasopressin) or no vasopressor use. Vasopressors were administered to 225 patients (30%) during OR; 59 patients (8%) received multiple vasopressors. Patients who received vasopressors were older, more severely injured, had worse vital signs, and increased mortality rate (all P < 0.001). EPI was independently associated with mortality (odds ratio, 6.88; P = 0.001). If patients who received EPI were excluded, there was no difference in mortality between those who received vasopressors alone or in combination and those that did not (5 vs 6%, P = 0.523), although multiple markers of injury severity were worse. We conclude that vasopressor use is relatively common in the most severely injured patients requiring OR and is associated with mortality. EPI is most often used for cardiac arrest, whereas other vasopressors are used for their vasoconstrictive properties. This suggests that, except for EPI, vasopressors during OR are not independently associated with mortality

Long-term coagulation changes after resection of thoracoabdominal malignancies

The purpose of this study was to evaluate the long-term coagulation status of patients undergoing malignancy resection. A prospective observational trial was conducted with informed consent in 52 patients (age 66 ± 10 years and 60% male) with thoracoabdominal tumors (pancreas [n = 18, 35%], esophagus [n = 13, 25%], liver [n = 7, 14%], stomach [n = 6, 12%], bile duct [n = 3, 6%], retroperitoneal [n = 3, 6%], and duodenum [n = 2, 4%]) with 6- to 12-month follow-up. Coagulation was evaluated with rotational thromboelastography (ROTEM) on whole blood and with a panel of hemostatic markers on stored plasma. Maximum clot firmness (MCF) in the intrinsic, extrinsic, and fibrinogen pathways increased immediately postoperatively and then decreased by 9.2 ± 4.1 months (p < 0.05). Markers of thrombin generation (prothrombin fragment 1 + 2, fibrinolysis [D-dimer], and endothelial activation [coagulation factor VIII]) were elevated at all time points. The ROTEM pattern depended on histologic type and cancer location. All esophageal tumors were adenocarcinoma and demonstrated similar patterns to the overall population, with MCF differences over time in all 3 pathways (all p < 0.05). Regarding tumors of the pancreas or liver, there were no statistically significant differences when comparing all 3 time periods, but there were time-related differences when evaluating only primary adenocarcinomas of the liver (all p < 0.05). Three patients (6%) developed venous thromboembolism (VTE) and had decreased clot formation time, increased angle, and increased MCF (all p < 0.05). Cancer patients at risk for VTE can be identified with a point-of-care ROTEM test and may benefit from additional anticoagulation. Biomarkers reflecting different functional hemostasis activity groups (fibrinolysis, thrombin generation, and endothelial activation) confirm the ongoing prothrombotic state. The ROTEM demonstrated increased hypercoagulability postoperatively, which returned to baseline in long-term follow-up. Reversal of cancer-induced hypercoagulability occurred in some patients and varied with tumor histology and location

Vasopressin for cerebral perfusion pressure management in patients with severe traumatic brain injury: preliminary results of a randomized controlled trial

After traumatic brain injury (TBI), catecholamines (CAs) may be needed to maintain adequate cerebral perfusion pressure (CPP), but there are no recommended alternative vasopressor therapies. This is an interim report of the first study to test the hypothesis that arginine vasopressin (AVP) is a safe and effective alternative to CAs for the management of CPP in patients with severe TBI. Since 2008, all TBI patients requiring intracranial pressure monitoring at this Level 1 trauma center have been eligible for a randomized trial to receive either CA or AVP if vasopressors were required to maintain CPP greater than 60 mm Hg. To date, 96 patients have been consented and randomized. Demographics, vital signs, and laboratory values were similar. As treated, 60 required no vasopressors and were the least severely injured group with the best outcomes. Twenty-three patients received CA (70% levophed, 22% dopamine, 9% phenylephrine) and 12 patients received AVP. The two vasopressor groups had similar demographics, but Injury Severity Score (ISS) and fluid requirements on intensive care unit Day 1 were worse in the AVP versus the CA groups (all p < 0.05) before treatment. These differences indicate more severe injury with accompanying hemodynamic instability. Nevertheless, adverse events were not increased with AVP versus CA. Trends favored AVP versus CA, but no apparent differences were statistically significant at this interim point. There was no difference in mortality rates between CA and AVP. These preliminary results suggest that AVP is a safe and effective alternative to CA for the management of CPP after TBI and support the continued investigation and use of AVP when vasopressors are required for CPP management in TBI patients. Therapeutic study, level II

Identifying Pitfalls in Chest Tube Insertion: Improving Teaching and Performance

Chest tube thoracostomies are common surgical procedures, but little is known about how practitioners learn the skill. This study evaluates the frequency with which correctly performed tasks are executed by subjects during chest tube thoracostomies. In this prospective study, we developed a mobile-learning module, containing stepwise multimedia guidance on chest tube insertion. Next, we developed and tested a 14-item checklist, modeled after key skills in the module. Participants, defined as “novice” (fewer than 10 chest tubes placed) or “expert” (10 or more placed), were assigned to either the video or control group. A trained clinician used the checklist to rate participants while they inserted a chest tube on a TraumaMan simulator. University of Miami, Miller School of Medicine, a tertiary care academic institution. Current medical students, residents, and the United States Army Forward Surgical Team members rotating through the institution. One hundred twenty-eight subjects entered and finished the study. One hundred twenty-eight subjects enrolled in the study; 86 (67%) were residents or US Army Forward Surgical Team members, 66 (77%) were novices, and 20 (23%) were experts. Novices most frequently connected the tube to suction (91%), adequately dissected the soft tissue (82%), and scrubbed or anesthetized appropriately (80%). They least frequently completed full finger sweeps (33%), avoided the neurovascular bundle (35%), and performed a controlled pleural puncture (39%). Comparing the novice video group with the novice control group, the video group was more likely to correctly perform a finger sweep (42%, p<0.001) and clamp the distal end of the chest tube (42%, p<0.001). Of all the steps, experts least frequently completed full finger sweeps (70%) and avoided the neurovascular bundle (75%). Comparing the expert video group with the expert control group, the video group was more likely to correctly perform finger sweeps, the incision, and clamping the distal chest tube (20%, p = not significant). Avoiding the neurovascular bundle, controlled pleural entry, and finger sweeps are most often performed incorrectly among novices. This information can help instructors to emphasize key didactic steps, possibly easing trainees' learning curve