Retromuscular drain output at removal does not influence adverse outcome rate in open ventral hernia repairs

Background: Retromuscular drains are commonly placed during retromuscular hernia repair (RHR) to decrease postoperative wound complications and help mesh in-growth. Drains are traditionally removed when output is low but the relationship between drain output at the time of removal and postoperative complications has yet to be delineated. This study aimed to investigate outcomes of RHR patients with drain removal at either high or low output volume. Methods: An institutional review board-approved retrospective chart review evaluated adult patients undergoing open RHR with retromuscular drain placement between 2013 and 2022 at a single academic medical center. Patients were stratified into low output drainage (LOD, < 50 mL/day) or high output drainage (HOD, ≥ 50 mL/day) groups based on volume on the day of drain removal. Results: We identified 336 patients meeting inclusion criteria: 58% LOD (n = 195) and 42% HOD (n = 141). Demographics and risk factors pertaining to hernia complexity were similar between cohorts. Low-drain output at the time of removal was associated with a significantly longer drain duration (6.3 ± 4.5 vs. 4.4 ± 1.6 days, p < 0.001) and postoperative hospital stay (5.9 ± 3.6 vs. 4.8 ± 2.8 days, p < 0.001). With a 97% 30-day follow-up, incidence of surgical site occurrence (SSO) was not statistically different between groups (29.2% LOD, 26.2% HOD, p = 0.63). Surgical site infection and SSO requiring procedural intervention was also not statistically significant between cohort. At 1-year follow-up, hernia recurrence rates were the same between groups (4.2% LOD, 1.4% HOD, p = 0.25). Conclusion: Following open ventral hernia repair with retromuscular mesh placement, the rate of postoperative wound complications was not statistically different based on volume of drain output day of removal. These results suggest that removing drains earlier despite higher output is safe and has no effect on short- or long-term hernia outcomes.