Dalteparin safe for DVT prophylaxis among those with renal insufficiency

Deep vein thrombosis prophylaxis with the low–molecular-weight heparin dalteparin was not associated with an excessive anticoagulant effect among critically ill patients with severe renal insufficiency.

Physicians have tended to avoid the use of low–molecular-weight heparin among patients with impaired renal function because of a fear of an excessive anticoagulant effect that could increase the risk of bleeding. Previous data, however, support the idea that dalteparin sodium 5,000 IU once daily may not confer this risk, and the present study was undertaken to challenge the existing treatment patterns.

A total of 138 critically ill patients were included in the study, all with creatinine clearance less than 30 mL/min. The median dalteparin exposure duration was seven days. Bioaccumulation (excessive coagulation effect), defined by measurements of trough anti-Xa level greater than 0.40 IU/mL, was not found in any of the 120 patients with at least one measurement. The median trough anti-Xa level was undetectable. The investigators noted that trough anti-Xa levels are approved by consensus groups as a measurement of the anticoagulation effect of low–molecular-weight heparins.

DVT occurred in seven of 138 patients (5.1%), and major bleeding occurred in 10 patients (7.2%). All bleeding patients had trough anti-Xa levels of 0.18 IU/mL or lower.

“These findings challenge the premise that DVT prophylaxis with low–molecular-weight heparins should be avoided in patients with renal insufficiency, including patients with severe renal insufficiency,” the researchers wrote. “Furthermore, although we studied critically ill patients, we believe our findings may be generalizable to noncritically ill patients with severe renal insufficiency and to patients with mild to moderate renal insufficiency.”

Arch Intern Med. 2008;168:1805-1812.