Infections after mastectomy and tissue expander placement: A multivariate regression analysis.

Background: While breast surgery is considered a clean case, tissue expander-based breast reconstruction (TE-BR) has infection rates quoted up to 31%, decidedly higher than the typical 1% to 2% rate of surgical site infections. Through multivariate regression, we sought to analyze risk factors that contribute to infections following TE placement.

Methods: A retrospective study reviewed all patients undergoing mastectomy with immediate or delayed TE placement over a 22-month period. Infections were defined as clinically documented cellulitis or infection, return to the operating room (RTOR) for suspected infection, or positive operative or seroma cultures.

Results: A total of 311 patients underwent mastectomy and TE placement to 490 breasts. 13.5% of breasts developed an infection prior to second stage reconstruction. Multivariate logistic regression indicated that patients who developed infections were older (52.8 vs. 47.6 years, OR 1.04, p = 0.02), had higher rates of full-thickness necrosis (24.6% vs. 3.6%, OR 6.64, p<0.01), had higher rates of seromas requiring drainage (33.3% vs. 11.5%, OR 2.79, p<0.01), and had longer periods of drain therapy (24.9 vs. 21.0 days, OR 1.04, p = 0.04). Logistic regression established that longer discharge antibiotic length was not protective against the development of infection.

Conclusion: Patients were more likely to develop an infection as the length of surgical drain retention increased, patient age increased, or if they developed seromas and full-thickness necrosis. Longer post-operative antibiotics were not protective against the development of infection in this sample. Prospective studies are needed to assess how antibiotic lengths can affect the morbidity of patients undergoing TE-BR.