What’s the Claim
A study of nearly 800 patients who underwent digital replantation or revascularization (the latter defined as a partially severed digit with vascular compromise) found no overall benefit to therapeutic dosing of IV heparin in terms of digit survival, and no benefit to using it in any of several higher-risk subgroups with more severe injury patterns. By contrast, those treated with heparin were much more likely (adjusted odds ratio 10.6 [95% CI 6.7 to 17.1]) to have experienced a serious bleeding complication.
How’s It Stack Up?
The debate about whether to use heparin after digital replantation has been going on for a long time. This study is in good company in that most studies on the topic seem to show no benefit of anticoagulation and a higher apparent risk of bleeding. The problem is that many of these studies, including the current one, have been observational, and it’s likely that patients with “tougher” presentations (more-severe injuries and/or more risk factors for complications) received heparin. For that reason, we need to seek guidance from randomized trials or other kinds of higher-quality evidence, which necessarily will be smaller than long-term observational studies like this one. There is some — though not much — to be found, including a Cochrane review summarizing four randomized trials about low-molecular-weight heparin (though the comparator in one study was unfractionated heparin and it was no heparin in another) and a narrative systematic review that considered six studies meeting prespecified inclusion criteria that evaluated unfractionated heparin. Neither of those found a benefit to anticoagulation. Taken in context, the main finding here seems very likely to be true.
What’s Our Take?
Heparin is a serious intervention that carries real risk. That much seems true from nearly every study that has looked at its use in this context. The burden of proof therefore should fall on those who recommend using it. It should take more than the force of habit, anecdote, or reliance on orthopaedic tradition to support a practice like this. The combination of randomized trials showing no benefit to anticoagulation when used relatively unselectively and this large study finding no benefits to its use (as well as some serious potential harms) either in general or in subgroups of patients with more-severe injuries puts the ball deep in the court of those who believe heparin should be used (especially as a matter of routine) after digital replantation or revascularization surgery.
Zhu LM, Baradaran A, Thibaudeau S, Mastropasqua B. The Role of Intravenous Heparin Following Digital Replantation: A Retrospective Cohort Study on 1,155 Digits. J Hand Surg Am. 2023;48:263-272.