A new analysis of data shows the medical community may need to rethink the optimal strategy for treating blood clots and bleeding in hospitalized COVID-19 patients. Patients with COVID-19 in the intensive care unit (ICU) prescribed full-dose blood thinners were significantly more likely to experience heavy bleeding than patients prescribed a smaller yet equally effective dose - nearly 1 in 7 COVID-19 patients in the ICU experienced severe bleeding when given full-dose blood thinners. Almost all patients who experienced significant bleeding were mechanically ventilated and receiving full-dose anticoagulants (blood thinners).

Previous reports have found that 17% of hospitalized COVID-19 patients experience blood clots, says first author Maya Chilbert, PharmD, University at Buffalo clinical assistant professor.

The authors analyzed the outcome of blood clot treatments and the rate of bleeding events for more than 150 patients with COVID-19 who received either of two blood thinner regimens: a full-dose based on patient levels of D-dimer (a protein present in the blood after a blood clot dissolves), and the other a smaller but higher-than-standard dosage.

The average patient age was 58, and all experienced elevated levels of D-dimer, fibrinogen (a protein that helps the body form blood clots), and prothrombin time (a test that measures the time it takes for blood plasma to clot).

Nearly 14% of patients who received full-dose blood thinners experienced a significant bleeding event, compared to only 3% of patients who received a higher-than-standard dosage. All patients who experienced bleeding events were mechanically ventilated. No difference was reported in the regimens’ effectiveness at treating blood clots.