Surgical drainage after limb salvage surgery and endoprosthetic reconstruction: is 30 mL/day critical?

BACKGROUND: Periprosthetic infection is a major cause of failure after segmental endoprosthetic reconstruction. The purpose of this study is to determine whether certain aspects of drain output affect infection risk, particularly the 30 mL/day criterion for removal.
METHODS: Two hundred and ninety-five patients underwent segmental bone resection and lower limb endoprosthetic reconstruction at one institution. Data on surgical drain management and occurrence of infection were obtained from a retrospective review of patients' charts and radiographs. Univariate and multivariate Cox regression analyses were performed to identify factors associated with infection.
RESULTS: Thirty-one of 295 patients (10.5%) developed infection at a median time of 13 months (range 1-108 months). Staphylococcus aureus was the most common organism and was responsible for the majority of cases developing within 1 year of surgery. Mean output at the time of drain removal was 72 mL/day. Ten of 88 patients (11.3%) with ≤ 30 mL/day drainage and 21 of 207 patients (10.1%) with > 30 mL/day drainage developed infection (p = 0.84). In multivariate analysis, independent predictive factors for infection included sarcoma diagnosis (HR 4.13, 95% CI 1.4-12.2, p = 0.01) and preoperative chemotherapy (HR 3.29, 95% CI 1.1-9.6, p = 0.03).
CONCLUSION: Waiting until drain output is < 30 mL/day before drain removal is not associated with decreased risk of infection for segmental endoprostheses of the lower limb after tumor resection. Sarcoma diagnosis and preoperative chemotherapy were independent predictors of infection.