Abstract
Purpose: There are multiple dependent variables commonly attributed to survival of replanted digits. The ischemia time is thought to be a clinically relevant factor. However, controversy exists as large hand centers have reported successful replant outcomes independent of ischemic time. In this study, we present a single institution experience on the effect of ischemia time on the survival of completely amputated digits. Methods: A retrospective review of a single institution experience was performed. This cohort included all comers who had suffered complete amputation of a digit (Zone 2-4) and underwent replantation from 2003 to 2009. Demographic information as well as injury mechanism, ischemic time, and replantation outcome were recorded for each patient. Chi-square was used to analyze the result. Results: Mean age was 35.5 years old (2-69). Mean replantation survival was 89.5% (37/317). Survival rates were 94, 88, and 88% in respective groups of 0~6, 6~12, of > 12 hours of ischemia time. In chi-square analysis, there was no difference with $p$ value of 0.257. No other independent patient factors showed statistically significant relationship to replant survival rate. In the group with longest ischemia time (12~18 hours) replant survival rate was 88% (37/42). Conclusion: Prolonged ischemia time is commonly believed to be a contributing factor for replant survival. However, our experience has shown that survival rate is uniform up to 18 hours of ischemia.