Analysis of Flap Weight and Postoperative Complications Based on Flap Weight in Patients Undergoing Microsurgical Breast Reconstruction.

 Higher body mass index (BMI) has been shown to increase postoperative complications in autologous breast reconstruction. However, the correlation with flap weight is unknown. Here, we explore the relationship of flap weights and complication rates in patients undergoing microvascular breast reconstruction.  Retrospective chart review identified all patients undergoing microvascular breast reconstruction with abdominally based flaps at a single institution between November 2007 and April 2013. Breasts with documented flap weight and 1-year follow-up were included. Patients undergoing stacked deep inferior epigastric perforator flaps were excluded. Breasts were divided into quartiles based on flap weight and examined by demographics, surgical characteristics, complications, and revisions.  A total of 130 patients undergoing 225 flaps were identified. Patients had a mean age of 50.4 years, mean BMI of 27.1 kg/m, and mean flap weight of 638.4 g (range: 70-1640 g). Flap weight and BMI were directly correlated. Flaps were divided into weight-based quartiles: first (70-396 g), second (397-615 g), third (616-870 g), and fourth (871-1640 g). There were no associations between flap weight and incidences of venous thrombosis, arterial thrombosis, hematoma, flap loss, fat necrosis, or donor site hernia. However, increased flap weight was associated with increased rate of donor site wound healing problems in both univariate and multivariate analysis.  Increased flap weight is not associated with added flap complications among patients undergoing microvascular breast reconstruction, however, patients with flaps of 667.5 g or more are more likely to have donor site healing problems. The success and evidence contrary to previous studies may be attributed to surgeon intraoperative flap choice.