Clinical Citations: Managing acute VTE: Is SQ unfractionated heparin an option?

A major disadvantage of unfractionated heparin is its intravenous administration and the need for coagulation monitoring and hospitalization. However, subcutaneous administration may be an alternative, according to Kearon and coworkers. They found that fixed-dose subcutaneous unfractionated heparin appears to be as effective and safe as low molecular weight heparin (LMWH) for the outpatient treatment of acute venous thromboembolism (VTE).

Their study included 697 patients with acute VTE, who were randomly assigned to receive either subcutaneous unfractionated heparin (initial dose of 333 U/kg, followed by a fixed dose of 250 U/kg every 12 hours) or subcutaneous LMWH (100 IU/kg every 12 hours).

The incidence of recurrent VTE was 3.8% in the group that received unfractionated heparin and 3.4% in the LMWH group. The incidence of major bleeding in the first 10 days of treatment was 1.1% and 1.4%, respectively. Treatment was administered entirely out of the hospital in 72% of the group that received unfractionated heparin and in 68% of the group that received LMWH.

The authors note that their findings question the value of monitoring activated partial thromboplastin time in patients who are receiving the recommended dosages of unfractionated heparin.