Venous Thromboprophylaxis in Critically Ill Adults

Venous thrombosis
A systematic review compared the efficacy and safety of prophylaxis agents for preventing venous thromboembolism in critically ill adults.

Low-molecular-weight heparin (LMWH) was most effective in reducing the incidence of deep vein thrombosis (DVT) among critically ill adults compared with other pharmacologic and mechanical therapies, according to findings published recently in Chest.

Increased risk of venous thromboembolism in critically ill adults can be treated with various agents for venous thromboprophylaxis. Researchers sought to compare the efficacy and safety of prophylaxis agents for critically ill adults to prevent venous thromboembolism (VTE). To accomplish this, researchers conducted a systematic review and network meta-analysis of randomized clinical trials (RCTs) from databases including PubMed, EMBASE, and Medline from inception through January 2021. The search yielded data on 9619 patients. Of those, (1) at least 80% were in the intensive care unit (ICU) receiving pharmacologic, mechanical, or combination pharmacologic and mechanical therapy for thromboprophylaxis, or placebo, or no thromboprophylaxis; and (2) at least 80% were 16 years of age or older. Grading of Recommendations Assessment, Development, and Evaluation (GRADE) was used to rate certainty of effect estimates. The study’s critical outcome was the incidence of all lower extremity DVT (proximal or distal) within 90 days of ICU admission. Control treatments included no prophylaxis, placebo, or use of compression stockings only.

Researchers discovered that LMWH, compared with control treatments, reduced incidence of deep vein thrombosis (DVT) (odds ration [OR], 0.59 [95% credible interval [CrI], 0.33-0.90]; high certainty), and, unfractionated heparin (UFH) may reduce the incidence of DVT (OR, 0.82 [95% CrI, 0.47-1.37]; low certainty). Compared with unfractionated heparin, LMWH probably reduces DVT (OR, 0.72 [95% CrI, 0.46-0.98]; moderate certainty). Low certainty evidence suggests compressive devices may reduce risk of DVT compared with control treatments (OR, 0.85 [95% CrI, 0.50-1.50]). Compared with either therapy alone, combined therapy (pharmacologic plus mechanical) showed an unclear effect on DVT (very low certainty).

Researchers determined that compared with control treatment among critically ill adults, LMWH reduces incidence of DVT and UFH and mechanical compressive devices may reduce the risk of DVT. Researchers concluded, “LMWH is probably more effective than UFH in reducing incidence of DVT and should be considered the primary pharmacologic agent for thromboprophylaxis.” The researchers also concluded that the efficacy and safety of combination mechanical compressive devices and pharmacologic therapy was unclear.

This review has important limitations. Some of these include: the inability to examine whether drug dose influenced efficacy; insufficient RCTs involving various LMWH agents; and lack of recent studies examining therapeutic dose parenteral anticoagulation for DVT prevention in seriously ill patients with COVID-19.

Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.


Fernando SM, Tran A, Cheng W, et al. VTE prophylaxis in critically ill adults: A systematic review and network meta-analysis. Chest. 2022;161(2):418-428. doi:10.1016/j.chest.2021.08.050