Risk factors for mastectomy flap necrosis following immediate tissue expander breast reconstruction

Abstract

Tissue expander placement is a mainstay of reconstructive surgery in the post-mastectomy patient. Necrosis of the native breast tissue is one of the most significant concerns in their post-operative care. The goal of this study is to elucidate factors that confer risk of this outcome. Chart review was conducted for a consecutive series of immediate tissue expander reconstructions by the two senior authors. Data was collected for several preoperative and intraoperative variables, as well as the outcome of mastectomy flap necrosis. Of the 1566 breasts that were examined, 135 (8.6%) experienced flap necrosis. The cohorts with and without flap necrosis were well matched. Those with the outcome of interest had significantly higher rates of switching to an autologous method of reconstruction (31.9% vs 6.2%, p < 0.001). Regression analysis revealed smoking status, increased age, tumescent mastectomy technique, and high (>66.67%) intraoperative tissue expander fill to confer increased risk of mastectomy flap necrosis. While smoking and older age are well-supported by the literature, tumescent technique and tissue expander fill are more novel points of discussion, which may serve as proxies for other issues. Awareness of these risk factors and their interplay will aid in clinical judgement and postoperative care of these patients.     

A predictive model of risk and outcomes in tissue expander reconstruction: A multivariate analysis of 9786 patients

Abstract

Outcomes of tissue expander breast reconstruction show variability based on presurgical risk factors. Few comprehensive, multi-institutional risk analyses exist. Patients who underwent tissue expander reconstruction were identified in a multi-institutional registry that spans over 240 institutions with over 200 variables per patient. Bivariate analysis of preoperative variables was performed across outcomes. Multivariate logistic regression was used to adjust for confounders and identify risk factors for complications. In 9786 total tissue expander patients, 526 (5.38%) patients experienced one or more complications. Wound infection and reoperations occurred in 3.45% and 6.76% of patients, respectively. Body mass index (BMI) was found to be a significant independent risk factor for overall morbidity, reoperation, prosthesis failure, and wound infection. Overweight, obese, and morbidly obese patients were at 1.7-, 2.6-, and 5.1-times greater risk of morbidity, respectively (p < 0.001 for all). Reconstructive timing, combined surgical procedures, and neoadjuvant chemotherapy were not found to be significant predictors of morbidity. The odds of developing complications were 1.5- and 1.3-times greater in smokers and patients over the age of 50, respectively (p = 0.001 and p = 0.015). For each additional hour of surgery, the odds of morbidity increased 1.26-times (p < 0.001). Precise risk profiles garnered from multi-institutional studies can help improve patient selection and education. Overall, tissue expander reconstruction was found to be safe, with relatively few complications. Operative time, BMI, and smoking were consistently found to be independent risk factors for postoperative morbidity.