The quality of evidence is downgraded by study limitations (lack of/unclear allocation concealment and blinding).
A Cochrane review [Abstract] 1 included 31 studies with a total of 2 958 subjects (mainly women and elderly). Ten studies (n=826) compared unfractionated heparin (UFH) with control, and 5 studies (n=373) compared low molecular weight heparin (LMWH) with control for prevention of deep venous thrombosis (DVT) and pulmonary embolism (PE) after surgery for hip fracture. The studies showed a reduction in the incidence of DVT (table T1). There were insufficient data to confirm the efficacy of either agent in the prevention of pulmonary embolism (RR for any PE 1.00, 95% CI 0.49 to 2.02; 10 studies, n=858 and RR for fatal PE 0.47, 95% CI 0.19 to 1.14; 8 studies, n=730). There was no statistically significant difference in overall mortality (RR 1.16, 95% CI 0.77 to 1.74; 8 studies, n=730). Data were inadequate for all other outcomes including wound complications.
There was insufficient evidence from 5 studies (n=644) to establish if LMWH was superior to unfractionated heparin.
| Intervention | RR (95% CI) | Participants (studies) |
|---|---|---|
| Any heparin | 0.60 (0.50 to 0.71) | 993 (13) |
| Any heparin (good quality studies) | 0.56 (0.41 to 0.75) | 326 (5) |
| LMWH | 0.63 (0.42 to 0.94) | 177 (3) |
| UFH | 0.59 (0.49 to 0.72) | 816 (10) |
Five studies (n=487) tested mechanical pumping devices. Mechanical pumping devices reduced DVT (RR 0.31, 95% CI 0.19 to 0.51; 5 studies, n=450) and pulmonary embolism (RR 0.40, 95% CI 0.17 to 0.96; 5 studies, n=487). Data were insufficient to establish any effect on the incidence of fatal pulmonary embolism and overall mortality. Problems with skin abrasion and compliance were reported.
The following decision support rules contain links to this evidence summary:
Primary/Secondary Keywords