Appropriate Use of Intravenous Unfractionated Heparin after Digital Replantation: A Randomized Controlled Trial Involving Three Groups

BACKGROUND:The purpose of this study was to clarify the appropriate use of unfractionated heparin as an anticoagulation agent after digital replantation. METHODS:This study was a prospective, randomized, single-blind, blinded-endpoint method, three-arm, parallel-group, controlled clinical trial conducted at a single institution. A total of 88 patients (101 fingers) following digital amputation and subsequent repair by anastomosis of both arteries and veins were randomly allocated into three groups(1) control group (no heparin dose), (2) low-dose heparin group (10,000 IU/day), and (3) high-dose heparin group (start at 15,000 IU/day, then adjust the dose to achieve an activated partial thromboplastin time of 1.5 to 2.5 times the baseline). The outcomes were assessed regarding the proportion of success at 2 weeks after replantation of amputated digits, total or partial necrosis, and occurrence of complications. RESULTS:No significant differences were found among the three groups, except for complications of congestion. The odds ratio of the heparin group compared with the control group for a success proportion was 5.40 (95 percent CI, 0.85 to 34.20; p = 0.027) in subjects aged 50 years or older. Significant elevations of activated partial thromboplastin time, aspartate transaminase, and alanine aminotransferase occurred in high-dose heparin groups on day 7. CONCLUSION:Unfractionated heparin administration is considered effective for patients aged 50 years or older, although the routine use of unfractionated heparin is not necessary after digital replantation. CLINICAL QUESTION/LEVEL OF EVIDENCE:Therapeutic, II.