Diagnosis and Treatment of Trauma-Induced Coagulopathy by Viscoelastography.

This article explores the application of viscoelastic tests (VETs) in trauma-induced coagulopathy and trauma resuscitation. We describe the advantages of VETs over conventional coagulation tests in the trauma setting and refer to previous disciplines in which VET use has reduced blood product utilization, guided prohemostatic agents, and improved clinical outcomes such as the mortality of critically bleeding patients. We describe different VETs and provide guidance for blood component therapy and prohemostatic therapy based on specific VET parameters. Because the two most commonly used VET systems, rotational thromboelastometry and thromboelastography, use different activators and have different terminologies, this practical narrative review will directly compare and contrast these two VETs to help the clinician easily interpret either and use the interpretation to determine hemostatic integrity in the bleeding trauma patient. Finally, we anticipate the future of new viscoelastic technologies that can be used in this setting.

Weight-based enoxaparin thromboprophylaxis in young trauma patients: analysis of the CLOTT-1 registry.

Introduction: Optimal venous thromboembolism (VTE) enoxaparin prophylaxis dosing remains elusive. Weight-based (WB) dosing safely increases anti-factor Xa levels without the need for routine monitoring but it is unclear if it leads to lower VTE risk. We hypothesized that WB dosing would decrease VTE risk compared with standard fixed dosing (SFD). Methods: Patients from the prospective, observational CLOTT-1 registry receiving prophylactic enoxaparin (n=5539) were categorized as WB (0.45-0.55 mg/kg two times per day) or SFD (30 mg two times per day, 40 mg once a day). Multivariate logistic regression was used to generate a predicted probability of VTE for WB and SFD patients. Results: Of 4360 patients analyzed, 1065 (24.4%) were WB and 3295 (75.6%) were SFD. WB patients were younger, female, more severely injured, and underwent major operation or major venous repair at a higher rate than individuals in the SFD group. Obesity was more common among the SFD group. Unadjusted VTE rates were comparable (WB 3.1% vs. SFD 3.9%; p=0.221). Early prophylaxis was associated with lower VTE rate (1.4% vs. 5.0%; p=0.001) and deep vein thrombosis (0.9% vs. 4.4%; p<0.001), but not pulmonary embolism (0.7% vs. 1.4%; p=0.259). After adjustment, VTE incidence did not differ by dosing strategy (adjusted OR (aOR) 0.75, 95% CI 0.38 to 1.48); however, early administration was associated with a significant reduction in VTE (aOR 0.47, 95% CI 0.30 to 0.74). Conclusion: In young trauma patients, WB prophylaxis is not associated with reduced VTE rate when compared with SFD. The timing of the initiation of chemoprophylaxis may be more important than the dosing strategy. Further studies need to evaluate these findings across a wider age and comorbidity spectrum. Level of evidence: Level IV, therapeutic/care management.

"Death Diamond" Tracing on Thromboelastography as a Marker of Poor Survival After Trauma.

BACKGROUND: Improvements in health care innovations have resulted in an enhanced ability to extend patient viability. As a consequence, resources are being increasingly utilized at an unsustainable level. As we implement novel treatments, identifying futility should be a focus. The "death diamond" (DD) is a unique thrombelastography (TEG) tracing that is indicative of failure of the coagulation system, with a mortality rate exceeding 90%. The purpose of this study was to determine if the DD was a consistent marker of poor survival in a multicenter study population. We hypothesize that the DD, while an infrequent occurrence, predicts poor survival and can be used to stratify patients in whom resuscitation efforts are futile. METHODS: A retrospective multi-institutional study of trauma patients presenting with TEG DDs between 8/2008 and 12/2018 at four American College of Surgeons trauma centers was completed. Demographics, injury mechanisms, TEG results, management, and survival were examined. RESULTS: A total of 50 trauma patients presented with DD tracings, with a 94% (n = 47) mortality rate. Twenty-six (52%) patients received a repeat TEG with 10 patients re-demonstrating the DD tracing. There was 100% mortality in patients with serial DD tracings. The median use of total blood products was 18 units (interquartile range 6, 34.25) per patient. DISCUSSION: The DD is highly predictive of trauma-associated mortality. This multicenter study highlights that serial DDs may represent a possible biomarker of futility.

Challenging Traditional Paradigms in Posttraumatic Pulmonary Thromboembolism.

Importance: Pulmonary clots are seen frequently on chest computed tomography performed after trauma, but recent studies suggest that pulmonary thrombosis (PT) and pulmonary embolism (PE) after trauma are independent clinical events. Objective: To assess whether posttraumatic PT represents a distinct clinical entity associated with the nature of the injury, different from the traditional venous thromboembolic paradigm of deep venous thrombosis (DVT) and PE. Design, Setting, and Participants: This prospective, observational, multicenter cohort study was conducted by the Consortium of Leaders in the Study of Traumatic Thromboembolism (CLOTT) study group. The study was conducted at 17 US level I trauma centers during a 2-year period (January 1, 2018, to December 31, 2020). Consecutive patients 18 to 40 years of age admitted for a minimum of 48 hours with at least 1 previously defined trauma-associated venous thromboembolism (VTE) risk factor were followed up until discharge or 30 days. Exposures: Investigational imaging, prophylactic measures used, and treatment of clots. Main Outcomes and Measures: The main outcomes of interest were the presence, timing, location, and treatment of any pulmonary clots, as well as the associated injury-related risk factors. Secondary outcomes included DVT. We regarded pulmonary clots with DVT as PE and those without DVT as de novo PT. Results: A total of 7880 patients (mean [SD] age, 29.1 [6.4] years; 5859 [74.4%] male) were studied, 277 with DVT (3.5%), 40 with PE (0.5%), and 117 with PT (1.5%). Shock on admission was present in only 460 patients (6.2%) who had no DVT, PT, or PE but was documented in 11 (27.5%) of those with PE and 30 (25.6%) in those with PT. Risk factors independently associated with PT but not DVT or PE included shock on admission (systolic blood pressure <90 mm Hg) (odds ratio, 2.74; 95% CI, 1.72-4.39; P < .001) and major chest injury with Abbreviated Injury Score of 3 or higher (odds ratio, 1.72; 95% CI, 1.16-2.56; P = .007). Factors associated with the presence of PT on admission included major chest injury (14 patients [50.0%] with or without major chest injury with an Abbreviated Injury Score >3; P = .04) and major venous injury (23 [82.1%] without major venous injury and 5 [17.9%] with major venous injury; P = .02). No deaths were attributed to PT or PE. Conclusions and Relevance: To our knowledge, this CLOTT study is the largest prospective investigation in the world that focuses on posttraumatic PT. The study suggests that most pulmonary clots are not embolic but rather result from inflammation, endothelial injury, and the hypercoagulable state caused by the injury itself.

Viscoelastic Testing and Coagulopathy of Traumatic Brain Injury.

A unique coagulopathy often manifests following traumatic brain injury, leading the clinician down a difficult decision path on appropriate prophylaxis and therapy. Conventional coagulation assays-such as prothrombin time, partial thromboplastin time, and international normalized ratio-have historically been utilized to assess hemostasis and guide treatment following traumatic brain injury. However, these plasma-based assays alone often lack the sensitivity to diagnose and adequately treat coagulopathy associated with traumatic brain injury. Here, we review the whole blood coagulation assays termed viscoelastic tests and their use in traumatic brain injury. Modified viscoelastic tests with platelet function assays have helped elucidate the underlying pathophysiology and guide clinical decisions in a goal-directed fashion. Platelet dysfunction appears to underlie most coagulopathies in this patient population, particularly at the adenosine diphosphate and/or arachidonic acid receptors. Future research will focus not only on the utility of viscoelastic tests in diagnosing coagulopathy in traumatic brain injury, but also on better defining the use of these tests as evidence-based and/or precision-based tools to improve patient outcomes.

The "Death Diamond": Death Beyond Trauma.

Thromboelastography (TEG) has become a critical tool for the diagnosis, assessment, and management of hyperfibrinolysis and coagulopathy in trauma. In 2015, Chapman et al. of the Denver group coined the term "Death Diamond" (DD) to describe a TEG tracing identified in a unique trauma population. The DD was associated with a 100 per cent positive predictive value for mortality. Given the potential prognostic implications and resource savings associated with validating the DD as a marker of futile care, we sought to further evaluate DD outcomes. A retrospective review of 6850 TEGs, 34 patients (24 trauma and 10 nontrauma), displayed a DD tracing. Through invasive procedures and transfusions, nine DD tracing "normalized," but, ultimately, this did not impact the outcome because the DD had a positive predictive value of 100 per cent for mortality in both populations. The median survival time in trauma patients was two hours compared with seven hours in nontrauma patients. Overall, this study further validates the predictive value of the DD in a trauma population while also serving as an assessment of the DD in a nontrauma population. Given these findings, a DD may prove to be an indicator of futile care. Further multicenter studies should be conducted to confirm these results.

The use of prognostic indicators in the development of a statistical model predictive for adrenal insufficiency in trauma patients.

We performed a retrospective chart review of trauma patients admitted to Palmetto Richland Memorial Hospital and identified 63 cases of adrenal insufficiency along with 65 trauma patient controls. Two statistical models, a neural network and a multiple logistic regression, were developed to predict patients with increased risk of developing adrenal insufficiency. Each model had 11 selected independent variables, along with patient demographic data, to make a probabilistic prediction of patient outcome. The neural network model was trained with 102 patients to identify linear and nonlinear relationships that could yield a predictive capability. The neural network achieved an accuracy of 71 per cent. The logistic regression model achieved an accuracy of 82 per cent. With these models, we have shown the feasibility of a method to more accurately screen patients with an increased risk of adrenal insufficiency. This ability should allow earlier identification and treatment of patients with adrenal insufficiency. Further development with a larger database is needed to improve the accuracy of the present models.

Cross-sectional and longitudinal association between antihypertensive medications and cognitive impairment in an elderly population.

BACKGROUND: The effect of antihypertensive medications on cognitive function has not been well studied. The authors' objectives were to investigate the cross-sectional and longitudinal association between the use of antihypertensive medications and cognitive function and to compare different antihypertensive medication classes with regard to this association in an elderly population. METHODS: The medical records of a convenience sample of patients (n = 993 cross-sectional and 350 longitudinal; mean age, 76.8 +/- 0.3 years; 74% women; 87% White) followed at a geriatric practice were reviewed. Data abstracted included demographics, medical history (Alzheimer's disease [AD] or vascular dementia [VaD]), use of antihypertensive medications, and results of cognitive assessments (the Mini-Mental Status Examination [MMSE] and the Clock Draw Test [CDT]). RESULTS: In the cross-sectional analysis, antihypertensive use was not associated with MMSE (p >.05), CDT (p >.05), or dementia diagnosis (odds ratio for AD, 0.8; 95% confidence interval [CI], 0.6 to 1.2; odds ratio for VaD, 1.6; 95% CI, 0.6 to 4.0). In the longitudinal analysis, antihypertensive use was associated with a lower rate of cognitive decline on the MMSE (-0.8 +/- 2 points in users vs -5.8 +/- 2.5 points in nonusers; p =.007) and on the CDT (-0.3 +/- 0.8 points in users vs -2.2 +/- 0.8 points in nonusers; p =.002), and with a lower risk for the development of cognitive impairment (odds ratio, 0.56; 95% CI, 0.38 to 0.83; p =.004). The trend was similar in patients with baseline AD (p =.02). Patients taking diuretics (p =.007), angiotensin-converting enzyme inhibitors (p =.016), and beta-blockers (p =.014) had a lower rate of cognitive decline, and patients taking angiotensin receptor blockers (p =.016) had improved cognitive scores. CONCLUSIONS: Antihypertensive use, particularly diuretics, angiotensin-converting enzymes inhibitors, beta-blockers, and angiotensin receptor blockers, may be associated with a lower rate of cognitive decline in older adults, including those with AD. Until a randomized clinical trial confirms our results, findings of this observational study should be interpreted with caution.

Mechanistic determinates of the acute coagulopathy of trauma (ACoT) in patients requiring emergency surgery.

INTRODUCTION: The development of acute coagulopathy of trauma (ACoT) is associated with a significant increase in mortality. However, the contributory mechanisms behind ACoT have yet to be clearly defined. The purpose of this study was to evaluate the influence of multiple variables, including base deficit and injury severity, on development of ACoT within a subset of critically ill trauma patients. METHODS: A retrospective review of all trauma laparotomies between 01/2004-12/2009 was performed. ACoT (+) was defined as an arrival INR ≥1.5, ACoT (-) defined as INR<1.5. Univariate and multivariate analyses were performed. RESULTS: Of 1218 patients, 337 (27%) were ACoT (+) and 881 (73%) were ACoT (-) upon presentation. Groups were similar in demographics, ED fluid administration, GCS scores, and admission temperatures. Admission base deficit (8.5 vs. 4, p<0.001) and ISS (median 25 vs. 16, p<0.001) were higher in the ACoT (+) group, as were intra-operative RBC (median 4 vs. 0 U) and plasma (3 vs. 0 U) transfusions; both p<0.001. Multiple-linear regression revealed INR values were independently associated with arrival base deficit and pre-hospital fluid volumes (both p<0.001). On logistic regression, the development of ACoT (+) was associated with base deficit (OR 0.92, p=0.013) as well as ISS (OR 1.05, p<0.001). However, blunt mechanism alone was not an independent predictor of ACoT. CONCLUSION: The current study revealed that ACoT is independently associated with both shock (base deficit) and tissue injury. Additionally, tissue injury is a significant contributor to the development of early ACoT regardless of blunt or penetrating mechanism.

Screening for thoracolumbar spinal injuries in blunt trauma: an Eastern Association for the Surgery of Trauma practice management guideline.

BACKGROUND: Thoracolumbar spine (TLS) injuries have an incidence rate of 5% in blunt trauma patients. The Eastern Association for the Surgery of Trauma published Practice Management Guidelines for the Screening of Thoracolumbar Spine Fracture in 2007. The Practice Management Guidelines Committee was assembled to reevaluate the literature. METHODS: A search of the United States National Library of Medicine and the National Institutes of Health database was performed using MEDLINE through PubMed (www.pubmed.gov). The search retrieved English-language articles from March 2005 to December 2011 that referenced traumatic TLS injuries and fractures. The questions posed were the following: (1) What is the appropriate imaging modality to screen patients for TLS injuries? (2) Which trauma patients require radiographic screening for TLS injuries? (3)Does a patient who is awake and alert without distracting injuries require radiologic workup to rule out TLS injuries? RESULTS: Thirty-seven articles that referenced traumatic TLS injuries in association with screening published between March 2005 and December 2011 were collected and disseminated to the committee. Twelve were found to be relevant. Nine publications from the previous 2006 guidelines were reviewed and referenced to create and validate the updated guidelines. CONCLUSION: Practice patterns have changed regarding screening blunt trauma patients for TLS injuries. Software reformatted multidetector computed tomographic scans are more sensitive and accurate than plain films. Multidetector computed tomographic scans have become the screening modality of choice and the criterion standard in screening for TLS injuries. The literature supports a Level 1 recommendation to validate this based on a preponderance of Class II data. Patients without altered mentation or significant mechanism may be excluded by clinical examination without imaging. Patients with gross neurologic deficits or concerning clinical examination findings with negative imaging should receive a magnetic resonance imaging expediently, and the spine service should be consulted.