Hematoma after mastectomy with immediate reconstruction: an analysis of risk factors in 883 patients.

BACKGROUND: Mastectomy followed by breast reconstruction presents unique circumstances, such as 2 operating teams, that may affect the likelihood of postoperative bleeding. This study evaluates risk factors for hematoma formation in patients undergoing mastectomy with immediate implant reconstruction.
METHODS: The charts of 883 patients (1199 breasts) who underwent mastectomy and immediate tissue expander reconstruction between April 1998 and August 2008 at a single institution were retrospectively reviewed. Demographic and operative factors and information on hematoma location were recorded. Fisher exact test, Student t test, and multiple linear regression were used for statistical analysis.
RESULTS: There were no differences in preoperative, operative, and oncologic characteristics between hematoma (n = 28 breasts) and nonhematoma (n = 1171 breasts) groups. Multiple linear regression analysis revealed no independent risk factors for hematoma formation, except an individual mastectomy and reconstructive surgeon (odds ratio, 3.58; 95% confidence interval, 1.03-12.37; P = 0.03; odds ratio, 2.54; 95% confidence interval, 1.06-6.08; P = 0.03, respectively). Most hematomas were diagnosed on postoperative day 0 or 1 (23/28, 82.1%) and found to originate from the pectoralis muscle (14/28, 50.0%) or axillary region (6/28, 21.4%).
CONCLUSIONS: The risk of postoperative hematoma after mastectomy with immediate reconstruction is not affected by any measurable preoperative, operative, or oncologic factors. With no definitive risk factor for bleeding, surgeons should remain meticulous and vigilant throughout the operation. In particular, hemostasis should be focused on the chest wall musculature given its propensity for being the primary source of hematoma formation.