Challenging Traditional Paradigms in Posttraumatic Pulmonary Thromboembolism

Abstract

IMPORTANCEPulmonary 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 MEASURESThe 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.

Platelet dysfunction after trauma: From mechanisms to targeted treatment

“…63,65 Post-injury arterial thrombosis is less frequently diagnosed and is associated with older age, indicating different underlying mechanisms. [66][67][68][69] Patients with VTE showed an increased maximum amplitude in VHA compared to patients without VTE. 62 Aggregation and platelet mapping remained impaired until day five of admission, 11,57,70 which is associated with development of VTE.…”

“…This hypercoagulable profile is associated with (venous) thromboembolic events (VTE) 63,65 . Post‐injury arterial thrombosis is less frequently diagnosed and is associated with older age, indicating different underlying mechanisms 66–69 . Patients with VTE showed an increased maximum amplitude in VHA compared to patients without VTE 62 .…”

Venous thromboembolism risk after spinal cord injury: A secondary analysis of the CLOTT study

“…This is a secondary analysis of the CLOTT 1 study data set. 10 CLOTT 1 was a prospective, multicenter, observational cohort study that included 17 major trauma centers in the United States. The study was funded by the Department of Defense and approved by the US Department of Defense Human Research Protection Office.…”

Advances in the Management of Coagulopathy in Trauma: The Role of Viscoelastic Hemostatic Assays across All Phases of Trauma Care

“…117 However, there have been repeated calls for better understanding and prophylaxis of VTE after trauma, as many patients continue to have thrombotic complications despite being appropriately treated early with heparin-based strategies. 118…”

“…117 However, there have been repeated calls for better understanding and prophylaxis of VTE after trauma, as many patients continue to have thrombotic complications despite being appropriately treated early with heparin-based strategies. 118 Alternative coagulation targets for reducing the risk for postinjury thrombotic complications have shifted toward antiplatelet medications in addition to heparin with retrospective data supportive of increased efficacy in reducing VTE. 119 Persistently low platelet levels following injury have been associated with postinjury thrombotic complications.…”