Objective: To identify the risk factors for a 30-day postoperative surgical site hematoma requiring evacuation (POH) after surgical resection of brain metastases. Methods: Patients who underwent surgical resection of brain metastases between 2011 and 2019 at our institution were included. Risk factors for a 30-day POH were identified using a multivariate logistic regression model. Results: A total of 158 patients were included in the analysis. The mean (SD) age of the study population was 59.3 (12.0) years, and 82 (53.2%) patients were female. The incidence of a 30-day POH was 8.2% (13 patients). There was no statistically significant association between the occurrence of a 30-day POH and overall mortality (p=0.100). On multivariate analysis, there was a statistically significant association between a 30-day POH and younger age (OR=0.91; 95% CI=0.83, 0.99; p=0.035), higher BMI (OR=1.61; 95% CI=1.16, 2.46; p=0.010), and blood type AB (OR=21.7; 95% CI=1.66, 522; p=0.031). On receiver operating characteristic analysis, a threshold BMI of 25.1 kg/m2 and threshold age of 57 gave the optimum balance of sensitivity and specificity in predicting the occurrence of a 30-day POH. Conclusions: Patients below 57 years old, who have a BMI of above 25, and/or have blood type AB were at higher risk of developing a 30-day POH after surgical resection of brain metastases. Additional care in intraoperative hemostasis and postoperative monitoring may be indicated among patients who have these risk factors.

The authors have declared no competing interest.

This study did not receive any funding

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