Venous thromboembolic complications in patients with severe and extremely severe COVID-19

Objective. To analyze the incidence and predictors of venous thromboembolic complications (VTEC) in COVID-19 patients ad-mitted to intensive care unit (ICU). Material and methods. A retrospective study recruited 200 ICU patients presenting with severe or critical COVID-19. Results. VTEC were found in 67 (33.5%) out of 200 patients. In 63 patients, deep and superficial vein thrombosis was observed. Four patients had pulmonary embolism. In 41 (20.5%) patients, VTEC occurred within the first day after admission to ICU. Patients presenting with VTEC had more extensive lung damage (CT data) and more common need for vasopressors (79.1% vs 59.4%, p=0.005) and mechanical ventilation (89.6% vs 60.2%, p=0.0001). Survival of these patients was lower (23 (34.3%) vs 76 (57.1%), p=0.003). There were significant differences in levels of von Willebrand factor antigen (vWF: Ag), interleukin 6 (IL-6), antithrombin III (AT III) and protein C. According to ROC analysis, vWF: Ag above 455% (AUC — 0.852 (0.69;1.00), p=0.008) was highly predictive for the risk of VTEC after 1 and 7 days. AT III below 72% (AUC — 0.77 (0.55;0.99), p=0.04) and IL-6 above 256 pg/ml (AUC — 0.85 (0.65;1.00), p=0.053) were prognostic factors of VTEC after the first day. Protein C below 81.5% at admission (AUC — 0.79 (0.59-0.99), p=0.042) was predictive regarding VTEC by the seventh day. Conclusion. Incidence of VTEC in ICU patients was 33.5%. In 60% of patients, VTEC developed before admission to ICU. vWF: Ag, AT III, IL-6, and protein C serve as predictors of VTEC in patients with severe or critical COVID-19. © 2021, Media Sphera Publishing Group. All rights reserved.