Gerardo A. Guarch

Venous thromboembolism after trauma: A never event?

Objective:Rates of venous thromboembolism as high as 58% have been reported after trauma, but there is no widely accepted screening protocol. If Medicare adds venous thromboembolism to the list of “preventable complications,” they will no longer reimburse for treatment, which could have devastating effects on many urban centers. We hypothesized that prescreening with a risk assessment profile followed by routine surveillance with venous duplex ultrasound that could identify asymptomatic venous thromboembolism in trauma patients. Design:Prospective, observational trial with waiver of consent. Setting:Level I trauma center intensive care unit. Patients:At admission, 534 patients were prescreened with a risk assessment profile. Interventions:Patients (n = 106) with risk assessment profile scores >10 were considered high risk and received routine screening venous duplex ultrasound within 24 hrs and weekly thereafter. Results:In prescreened high-risk patients, 20 asymptomatic deep vein thrombosis were detected with venous duplex ultrasound (19%). An additional ten venous thromboembolisms occurred, including six symptomatic deep vein thrombosis and four pulmonary emboli, resulting in an overall venous thromboembolism rate of 28%. The most common risk factors discriminating venous thromboembolism vs. no venous thromboembolism were femoral central venous catheter (23% vs. 8%), operative intervention >2 hrs (77% vs. 46%), complex lower extremity fracture (53% vs. 32%), and pelvic fracture (70% vs. 47%), respectively (all p < .05). Risk assessment profile scores were higher in patients with venous thromboembolism (19 ± 6 vs. 14 ± 4, p = .001). Risk assessment profile score (odds ratio 1.14) and the combination of pelvic fracture requiring operative intervention >2 hrs (odds ratio 5.75) were independent predictors for development of venous thromboembolism. The rates of venous thromboembolism for no chemical prophylaxis (33%), unfractionated heparin (29%), dalteparin (40%), or inferior vena cava filters (20%) were not statistically different (p = .764). Conclusions:Medicare’s inclusion of venous thromboembolism after trauma as a “never event” should be questioned. In trauma patients, high-risk assessment profile score and pelvic fracture with prolonged operative intervention are independent predictors for venous thromboembolism development, despite thromboprophylaxis. Although routine venous duplex ultrasound screening may not be cost-effective for all trauma patients, prescreening using risk assessment profile yielded a cohort of patients with a high prevalence of venous thromboembolism. In such high-risk patients, routine venous duplex ultrasound and/or more aggressive prophylactic regimens may be beneficial.

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

BACKGROUND 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. METHODS 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. RESULTS 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. CONCLUSION 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. LEVEL OF EVIDENCE Prognostic study, level III.

Does hemopericardium after chest trauma mandate sternotomy

BACKGROUND Recently, three patients with hemopericardium after severe chest trauma were successfully managed nonoperatively at our institution. This prompted the question whether these were rare or common events. Therefore, we reviewed our experience with similar injuries to test the hypothesis that trauma-induced hemopericardium mandates sternotomy. METHOD Records were retrospectively reviewed for all patients at a Level I trauma center (December 1996 to November 2011) who sustained chest trauma with pericardial window (PCW, n = 377) and/or median sternotomy (n = 110). RESULTS Fifty-five (15%) patients with positive PCW proceeded to sternotomy. Penetrating injury was the dominant mechanism (n = 49, 89%). Nineteen (35%) were hypotensive on arrival or during initial resuscitation. Most received surgeon-performed focused cardiac ultrasound examinations (n = 43, 78%) with positive results (n = 25, 58%). Ventricular injuries were most common, with equivalent numbers occurring on the right (n = 16, 29%) and left (n = 15, 27%). Six (11%) with positive PCW had isolated pericardial lacerations, but 21 (38%) had no repairable cardiac or great vessel injury. Those with therapeutic versus nontherapeutic sternotomies were similar with respect to age, mechanisms of injury, injury severity scores, presenting laboratory values, resuscitation fluids, and vital signs. Multiple logistic regression revealed that penetrating trauma (odds ratio: 13.3) and hemodynamic instability (odds ratio: 7.8) were independent predictors of therapeutic sternotomy. CONCLUSION Hemopericardium per se may be overly sensitive for diagnosing cardiac or great vessel injuries after chest trauma. Some stable blunt or penetrating trauma patients without continuing intrapericardial bleeding had nontherapeutic sternotomies, suggesting that this intervention could be avoided in selected cases. LEVEL OF EVIDENCE Therapeutic study, level III.

Repeat head computed tomography after minimal brain injury identifies the need for craniotomy in the absence of neurologic change.

BACKGROUND In this era of cost containment, the value of routine repeat head computed tomography (CT) in patients with mild TBI (mTBI) and no interval neurologic change has been challenged. The purpose of this study was to test the hypothesis that routine repeat head CT provides critical information after mTBI even with no neurologic change. METHODS From January 1996 to May 2010, records from all patients admitted to our Level I trauma center with an arrival Glasgow Coma Scale (GCS) score of 13 to 15 and at least one head CT were retrospectively reviewed. RESULTS In 360 patients with mTBI and positive initial head CT finding, the most common abnormalities were subarachnoid hemorrhage (64%), intraparenchymal hemorrhage (57%), and subdural hemorrhage (40%). Scans were repeated in 8 ± 6 hours; 11% were recalled, 59% remained stable, but 30% showed injury progression. Those patients with worsening repeat head CT finding had higher Injury Severity Score (ISS), were more likely to be intubated and require craniotomy, had longer stay, and had higher mortality (all p < 0.001). On multiple logistic regression, altered GCS score (odds ratio, 3.1–4.0), ISS (odds ratio, 1.1), and presence of mass effect (odds ratio, 2.0) were independently associated with worsening repeat head CT finding. In patients receiving a neurosurgical operative intervention, 32% to 59% had no clinical decline before the worsening repeat CT finding. CONCLUSION After mTBI, worsening of repeat head CT finding is seen in a third of patients and is associated with worse outcomes. A substantial fraction of patients who require operative intervention will have no clinical changes in the first 8 hours, supporting the value of repeat head CT within this time frame. LEVEL OF EVIDENCE Care management study, level III.

Admission Hematocrit and Transfusion Requirements after Trauma

BACKGROUND The decision to transfuse packed RBCs (PRBC) during initial resuscitation of trauma patients is based on physiologic state, evidence for blood loss, and potential for ongoing hemorrhage. Initial hematocrit (Hct) is not considered an accurate marker of blood loss. This study tests the hypothesis that admission Hct is associated with transfusion requirements after trauma. METHODS From June to December 2008, data from 1,492 consecutive admissions at a Level I trauma center were retrospectively reviewed to determine whether initial Hct was associated with PRBC transfusions. From October 2009 through October 2011, data from 463 consecutive transfused patients were retrospectively reviewed to determine whether Hct correlated with number of PRBC units received. RESULTS Packed RBC transfusion was not correlated with heart rate and was more highly correlated with Hct (r = -0.45) than with systolic blood pressure or base deficit (r = -0.32 or r = -0.26). Hematocrit was a better overall predictor than systolic blood pressure (sensitivity 45% vs 29%, specificity 94% vs 98%, area under receiver operator characteristic curve 0.71 vs 0.64). Lower Hct was associated with hypotension, more advanced shock, higher blood loss, and increased transfusion of PRBC, plasma, platelets, or cryoprecipitate (all, p < 0.01). CONCLUSION Admission Hct is more strongly associated with the PRBC transfusion than either tachycardia, hypotension, or acidosis. Admission Hct is also correlated with 24-hour blood product requirements in those receiving early transfusions. These findings challenge current thinking and suggest that fluid shifts are rapid after trauma and that Hct can be important in initial trauma assessment.

Long-term coagulation changes after resection of thoracoabdominal malignancies

BACKGROUND The purpose of this study was to evaluate the long-term coagulation status of patients undergoing malignancy resection. STUDY DESIGN 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. RESULTS 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). CONCLUSIONS 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.

BACKGROUND 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. METHODS 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. RESULTS 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. CONCLUSION 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. LEVEL OF EVIDENCE Therapeutic study, level II.

Coagulation Changes following Combined Ablative and Reconstructive Breast Surgery.

Background: This study assessed hemostatic function in cancer patients at high risk for venous thromboembolism. Methods: Thirty-eight female patients (age, 53 ± 9 years) undergoing immediate postmastectomy reconstruction were prospectively studied with informed consent. Blood was sampled preoperatively, on postoperative day 1, and at 1 week follow-up. Rotational thromboelastography clotting time, &agr;-angle (clot kinetics), clot formation time, and maximum clot firmness were studied with three different activating agents: intrinsically activated test using ellagic acid, extrinsically activated test with tissue factor, and fibrin-based extrinsically activated test with tissue factor and the platelet inhibitor cytochalasin D. Thromboprophylaxis was unfractionated heparin plus sequential compression devices if not contraindicated. Hypercoagulability was defined by one or more parameters outside the reference range. Results: Preoperatively, 29 percent of patients were hypercoagulable, increasing to 67 percent by week 1 (p = 0.017). Clotting time, clot formation time, and &agr;-angle remained relatively constant over time, but maximum clot formation increased in intrinsically activated test using ellagic acid, extrinsically activated test with tissue factor, and fibrin-based extrinsically activated test with tissue factor and the platelet inhibitor cytochalasin D (all p < 0.05). Body mass index was 28 ± 5 kg/m2, 23 percent received preoperative chemotherapy, and 15 percent had a history of tobacco use, but there was no association between these risk factors and hypercoagulability. Conclusions: Despite perioperative thromboprophylaxis, two-thirds of patients undergoing combined tumor resection and reconstructive surgery for breast cancer were hypercoagulable 1 week after surgery. Hypercoagulability was associated with increased clot strength mediated by changes in platelet and fibrin function. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Scald Burns From Hair Braiding.

Only one previous case report has described scald burns secondary to hair braiding in pediatric patients. The present case study is the largest to date of scald burns as a result of hair braiding in children and adults. Charts of all 1609 female patients seen at a single burn center from 2008 to 2014 were retrospectively reviewed to identify patients with scald burns attributed to hair braiding. Demographics, injury severity, injury patterns, and complications were analyzed. Twenty-six patients (1.6%) had scald burns secondary to hair braiding with median TBSA 3%. Eighty-five percent of patients were pediatric with median age 8 years. Injury patterns were as follows: back (62%), shoulder (31%), chest (15%), buttocks (15%), abdomen (12%), arms (12%), neck (12%), and legs (4%). No patients required operative intervention. Three patients were admitted to the hospital. Two patients required time off from school for 6 and 10 days post burn for recovery. Complications included functional limitations (n = 2), hypertrophic scarring (n = 1), cellulitis requiring antibiotics (n = 1), and anxiety requiring medical/psychological therapy (n = 2). This peculiar mechanism of injury not only carries inherent morbidity that includes the risks of functional limitations, infection, and psychological repercussions but also increases usage of resources through hospital admissions and multiple clinic visits. Further work in the form of targeted outreach programs is necessary to educate the community regarding this preventable mechanism of injury.