Prevention Of Deep Vein Thrombosis In Medical Patients By Low Dose Subcutaneous Heparin

In recent years it has been repeatedly shown that low-dose subcutaneous heparin reduces the incidence of deep vein thrombosis (D.V.T.) after major general surgery. By comparison, the prevention of thrombosis in medical patients has been little studied. A randomised trial was undertaken in one hundred patients with heart failure and/or chest infection to determine whether low-dose subcutaneous heparin reduced the frequency of D.V.T. in the legs. Heparin (5000 units 8 hourly), started within 12 hours of admission to hospital and continued until the patient was fully mobile, significantly reduced the frequency of D.V.T. diagnosed by the ¹²⁵I- fibrinogen scan technique, from 26% to 4% (p<0.01). Heparin did not cause bleeding problems except for a 20% incidence of injection site bruising. We therefore recommend prophylaxis with low dose subcutaneous heparin in patients with heart failure or chest infection who require more than 3 days’ bed rest.