Background: National guidelines recommend one dose of perioperative antibiotics for breast surgery and discourage postoperative continuation. However, reported skin and soft tissue infection (SSI) rates after mastectomy range from 1-26 %, higher than expected for clean cases. Utility of routine or selective postoperative antibiotic use for duration of drain presence following mastectomy remains uncertain.
Methods: This study included all female patients who underwent mastectomy without reconstruction at our institution between 2005 and 2012. SSI was defined using CDC criteria or clinical diagnosis of cellulitis. Information on risk factors for infection (age, body mass index [BMI], smoking status, diabetes, steroid use), prior breast cancer treatment, drain duration, and antibiotic use was abstracted from medical records. Multivariable logistic regression was used to assess the association between postoperative antibiotic use and the occurrence of SSI, adjusting for concurrent risk factors.
Results: Among 480 patients undergoing mastectomy without reconstruction, 425 had sufficient documentation for analysis. Of these, 268 were prescribed antibiotics (63 %) at hospital discharge. An overall SSI rate of 7.3 % was observed, with 14 % of patients without postoperative antibiotics developing SSI compared with 3.4 % with antibiotics (p < 0.0001). Factors independently associated with SSI were smoking and advancing age. Diabetes, steroid use, BMI, prior breast surgery, neoadjuvant chemotherapy, prior radiation, concomitant axillary surgery, and drain duration were not associated with increased SSI rates.
Conclusions: SSI rates among patients who did and did not receive postoperative antibiotics after mastectomy were significantly different, particularly among smokers and women of advanced age. These patient subgroups may warrant special consideration for postoperative antibiotics.