Venous Thromboembolism Events Following Venovenous Extracorporeal Membrane Oxygenation for Severe Acute Respiratory Syndrome Coronavirus 2 Based on CT Scans

Objectives The main objective of the study was to determine the prevalence of venous thromboembolism events in patients infected with severe acute respiratory syndrome coronavirus 2 requiring venovenous extracorporeal membrane oxygenation. The secondary objective was to compare venous thromboembolism events and coagulation variables in patients requiring venovenous extracorporeal membrane oxygenation according to the pathogen. Design Retrospective observational analysis at a single center. Setting Tertiary referral university teaching hospital. Patients Patients with severe acute respiratory syndrome coronavirus 2-related severe acute respiratory distress syndrome requiring venovenous extracorporeal membrane oxygenation therapy with an injected CT scan performed after extracorporeal membrane oxygenation retrieval. Interventions None. Measurements and main results We included 13 severe acute respiratory syndrome coronavirus 2 patients requiring venovenous extracorporeal membrane oxygenation. All of these patients experienced venous thromboembolism: 10 patients (76.9%) had isolated cannula-associated deep vein thrombosis, two patients (15.4%) had isolated pulmonary embolism, and one patient (7.7%) had both cannula-associated deep vein thrombosis and pulmonary embolism. Eleven patients (84.6%) had cannula-associated deep vein thrombosis. A jugular associated cannula-associated deep vein thrombosis was identified in seven patients (53.8%), a femoral associated cannula-associated deep vein thrombosis was identified in 10 patients (76.9%), and six patients (46.2%) had both femoral and jugular cannula-associated deep vein thrombosis. A pulmonary embolism was found in three patients (23.1%). No patient had central venous catheter-related deep vein thrombosis. One patient had thrombotic occlusion of the centrifugal pump, and one had oxygenator thrombosis requiring circuit replacement. Three patients (23.1%) had significant bleeding. Three patients (23.1%) had laboratory-confirmed heparin-induced thrombocytopenia, and all of them developed cannula-associated deep vein thrombosis. These three patients had femoral cannula-associated deep vein thrombosis, and two had an oxygenator or pump thrombosis. The mean activated partial thromboplastin time ratio was higher in the severe acute respiratory syndrome coronavirus 2 group than in the influenza group and the community-acquired pneumonia group (1.91 vs 1.48 vs 1.53; p = 0.001), which was also found in regard to the percentage of patients with an activated partial thromboplastin time ratio greater than 1.8 (47.8% vs 20% vs 20.9%; p = 0.003) and the mean prothrombin ratio (86.3 vs 61.6 vs 67.1; p = 0.003). There was no difference in baseline characteristics or venous thromboembolism events. Conclusions We report a 100% occurrence of venous thromboembolism in critically ill patients supported by venovenous extracorporeal membrane oxygenation for severe acute respiratory syndrome coronavirus 2-related acute respiratory distress syndrome using CT scan imaging despite a high target and close monitoring of anticoagulation.