Is long-term post-operative monitoring of microsurgical flaps still necessary?

Autologous microsurgical flap reconstruction has become commonplace in most plastic surgery units, and the success rates of this procedure have markedly increased over recent years. However, the possibility of flap failure still needs to be considered. A review of the literature reveals that the critical period for flap-threatening complications is the first 24-48 post-operative hours; however, the window for the onset of these complications remains open for up to 7 days post-operatively. In this study, we focus on the timing of flap complications, aiming to elucidate the time period over which meticulous flap monitoring can positively contribute to flap salvage rates. The relevant literature on the study topic was collated and reviewed in conjunction with the senior author's case series, which consisted of a total of 335 free flaps used during a 2-year period for breast and head and neck reconstruction or limb trauma. Patients' series were then divided into groups according to the complications timing. The correlation between the timing of complications and the flap salvage rate was investigated among the groups. Overall analysis of both the literature and our own data on 335 free flaps showed a progressive reduction in flap salvage rate during post-operative days; the correlations between the times of complication onset and the flap salvage rates in all groups were significant up to the third post-operative day. The correlations between salvage rates and later complications were not significant. Our results suggest that hourly flap monitoring should be compulsory during the first 48 post-operative hours, but clinical monitoring four times daily should be sufficient thereafter.