Timing of Unplanned Reoperation After Lower Extremity Free Flap Reconstruction: What Are the Roles of Procedure Indication and Defect Etiology?

[BACKGROUND] Advancements in lower extremity (LE) microsurgery have allowed for the expansion of indications for LE reconstructions. This project aims to better understand the temporal pattern and risk factors associated with LE free flap failure based on the clinical indication.

[MATERIALS AND METHODS] We analyzed all patients undergoing LE free flap reconstruction from the American College of Surgeons National Surgical Quality Improvement Program 2012-2019 prospectively collected data to determine rates and timing of reoperation. Free flaps were stratified by indication, type, and timing of reoperation. Weibull survival models were used to compare rates of takebacks among time intervals. Multivariable logistic regression was used to identify independent predictors for unplanned reoperation.

[RESULTS] Four hundred seven of LE free flaps were analyzed. There was a 14.5% rate (59/407) of unplanned reoperation within the first 30 postoperative days (PODs) after surgery. When stratified by the indication necessitating reoperation, patients with an underlying vascular indication had the highest rate of reoperation (40.9%). The reoperation rates were significantly different between indications (P < 0.05) The mean daily proportion of patients experiencing reoperation was highest during POD 0 to 2 (1.47% reoperations per day), which dropped significantly during POD 3 to 10 (0.55% per day) and again during POD 11 to 30 (0.28% per day, P < 0.05). African American race as well as malignant, prosthetic/implant, and wound/infectious indications were significant independent predictors for unplanned reoperation.

[CONCLUSIONS] Lower extremity reconstruction is an important reconstructive option for the coverage of a myriad of defects. Understanding the differences between postoperative reoperation timelines among indication subtypes is important for updated flap monitoring protocols, optimizing ERAS pathways, and beginning dangle protocols.