Optimizing perforator selection: A multivariable analysis of predictors for fat necrosis and abdominal morbidity in DIEP flap breast reconstruction

Background: This study aims to elucidate the important predicting factors for fat necrosis and abdominal morbidity in the patient undergoing deep inferior epigastric artery perforator flap reconstruction. Methods: The authors conducted a retrospective review of 866 free-flap breast reconstructions performed at one institution from 2010 to 2016. Twenty-eight potential predictors were included in multivariable analyses to control for possible confounding interactions. Results: Four hundred nine total deep inferior epigastric artery perforator flaps were included in the statistical analysis. Of these, 14.4 percent had flap fat necrosis, 21.3 percent had an abdominal wound or complication, and 6 percent had an abdominal bulge or hernia. Analysis showed an increase in the odds of fat necrosis with increasing flap weight (OR, 1.002 per 1-g increase; p = 0.0002). A decrease in the odds of fat necrosis was seen with lateral row (OR, 0.29; p = 0.001) and both medial and lateral row perforator flaps (OR, 0.21; p = 0.001), if indocyanine green angiography was used (OR, 0.46; p = 0.04), and with increasing total flow rate of the flap (OR, 0.62 per 1-mm/ second increase; p = 0.05). Increased odds of abdominal bulge or hernia were seen with lateral row or both medial and lateral row perforators (OR, 3.21; p = 0.05) versus medial row perforator-based flaps, and with patients who had an abdominal wound postoperatively (OR, 2.59; p = 0.05). Conclusions: The authors' results suggest that using larger caliber perforators and perforators from the lateral row alone, or in addition to medial row perforators, can decrease fat necrosis more than simply harvesting more perforators alone. However, lateral and both medial and lateral row perforator flaps come at the cost of increasing abdominal bulge rates.