Prevalence and risk factors for venous thromboembolic events in critically ill patients with SARS-CoV-2 infection: a prospective observational study.

Background The majority of prevalence studies on deep vein thrombosis (DVT) in severe COVID-19 patients are retrospective with DVT assessment based on clinical suspicion. Our aim was to prospectively and systematically estimate the occurrence of DVT in critically ill mechanically ventilated patients, and to identify potential risk factors for DVT occurrence and mortality. Methods All patients with COVID-19 admitted to our 45-beds intensive care unit (ICU) between March 6, 2020 and April 18, 2020 requiring invasive ventilatory support were daily screened for DVT with lower extremities and jugular veins ultrasonography. Univariate and multivariable logistic regression models were performed in order to identify predictors of DVT and mortality. Results Seventy-six patients were included in the final analysis (56 men, mean age 67 years, median SOFA 7 points, median SAPS II 41 points, median PaO2/Fi02 10.8 kPa). The period prevalence of DVT was 40.8%. Thirty-one DVTs were diagnosed. Twenty-five DVTs (80.6% of total DVTs) were catheter-related, mainly in the jugular veins. Twentysix DVTs (83.9%) occurred in patients receiving enhanced antithrombotic prophylaxis. No independent variable was predictive of DVT occurrence. Twenty-eight patients (36.8%) died during the ICU stay. Age and SOFA score were independently associated with mortality. Conclusions A high number of critically ill mechanically ventilated COVID-19 patients developed a DVT. The majority of DVTs were catheter-related and occurred under intensive prophylactic anticoagulation. Routine ultrasound of the jugular veins should be suggested in this patient population, and in particular in presence of a central venous catheter.