Incidence of Thrombotic Complications in COVID-19 Patients and the Impact of Antithrombotic Therapy on ICU Mortality.

Aim We aimed to determine the incidence of thrombotic complications and outcomes of critically ill COVID-19 patients admitted to the intensive care unit (ICU) and evaluate the association between combined antithrombotic therapy and mortality in ICU patients admitted for COVID-19 pneumonia. Methods We retrospectively collected data of adult critically ill patients with COVID-19 admitted to the ICU in a major hospital in Dubai during the COVID-19 pandemic. The primary outcome was in-hospital mortality. Secondary outcomes included the incidence of major complications, such as thrombotic complications during the ICU stay. The study population was classified into two groups based on the type of prophylactic anticoagulant and antiplatelet therapy received. Results The study included 257 ICU patients admitted with COVID-19 pneumonia. The mean duration of their ICU stay was 24.95 days, ranging from one day to 327 days. The primary outcome was in-hospital mortality. In our study, 151 patients (58.7%) suffered in-hospital mortality. Secondary outcomes included the incidence of major complications during the ICU stay. A total of 202 patients (78.6%) presented with acute respiratory distress syndrome. Ninety-nine (38.5%) of the patients had progressed to acute kidney injury. Thirty-three patients (12.8%) had various thrombotic complications. Three of these (9%) had venous thrombosis, and 30 patients (91%) had arterial thrombosis. Ischemic stroke was the major thrombotic complication of COVID-19 (36.3% of overall thrombotic events, n = 12), followed by myocardial infarction (27.2%; n = 9) and pulmonary embolism (21.2%; n = 7). Out of 257 COVID-19 ICU patients, 73 patients (28.4%) received both anticoagulants and antiplatelet therapy, and 183 patients (70.8%) received only anticoagulant therapy. We compared the mortality of COVID-19 ICU patients who received anticoagulants alone to those with added antiplatelets. The application of combined antiplatelet and anticoagulants as thromboprophylaxis for COVID-19 ICU patients was not associated with a significant reduction in mortality (P = 0.868). Peak serum levels of D-dimer significantly correlate with the length of ICU stay (rho = 0.137, P = 0.031). Peak D-dimer level during the ICU stay was statistically significantly higher in non-survivors (mean = 11.87) compared to survivors (mean = 8.59) (P < 0.001). D-dimer on ICU admission had a good prognostic value for ICU patients with COVID-19 infection (P = 0.018). Conclusion The incidence of thrombotic complications among COVID-19 pneumonia patients admitted to ICU is remarkably high, which reinforces the recommendation to apply thrombosis prophylaxis strictly to all ICU patients admitted with COVID-19. The application of combined antiplatelets with anticoagulants as thromboprophylaxis for COVID-19 ICU patients was not associated with a significant reduction in ICU mortality. D-dimer has a significant correlation with prognosis and length of ICU stay of COVID-19 patients.