Perioperative antibiotic prophylaxis in robotic-assisted ventral hernia repair: a propensity score-matched analysis

Routine antibiotic prophylaxis is widely used in the treatment of ventral hernias, although high-quality evidence supporting its necessity in modern minimally invasive procedures with extraperitoneal mesh placement is limited. Growing concerns regarding antimicrobial stewardship warrant a reassessment of this practice.

We conducted an ambidirectional cohort study with a historical (retrospective) control group of consecutive adult patients who underwent an rVHR (eTEP, TAPP, or eTEP/TAR) between June 2023 and December 2025 at a single tertiary center. Patients treated before January 2025 received single-shot prophylaxis as the institutional standard and were identified retrospectively from a prospectively maintained surgical database (historical control cohort); from January 2025 onwards, following a revised institutional protocol omitting routine prophylaxis, patients were enrolled prospectively and followed systematically through 90 days postoperatively (prospective intervention cohort). Patients were stratified based on the administration of perioperative single-shot antibiotic prophylaxis. To address potential selection bias, 1:1 nearest-neighbor propensity score matching (PSM) was performed with a caliper of 0.1 of the logit of the propensity score. The matching variables included a range of sociodemographic and health-related characteristics, including age, hernia category, BMI, ASA classification, diabetes status, smoking status, and the size of the hernia defect. The balance of the groups was evaluated using standardized mean differences (SMD, threshold < 0.10). The primary endpoints were defined as SSO and SSI at 30 and 90 days, while the secondary endpoints included LOS as well as univariate and multivariate odds ratios (OR). In addition, prespecified subgroup analyses were performed with respect to surgical technique, BMI class, smoking status, diabetes mellitus, anticoagulation, and wound class.

Of the 260 patients included in the study, 258 met the inclusion criteria, of whom 174 (67.4%) received antibiotic prophylaxis and 84 (32.6%) did not. PSM yielded 78 well-balanced pairs (all post-match SMDs ≤ 0.13, propensity score SMD 0.007). The rate of 30-day SSOs did not differ significantly between the matched groups (12.8% with prophylaxis vs. 15.4% without, McNemar p = 0.823), nor did the rate of 90-day SSOs (5.1% vs. 3.8%, p = 1.000). 30-day SSIs were rare and comparable between the groups (2.6% vs. 1.3%, p = 1.000); no SSIs occurred after 90 days. The median length of stay (LOS) was two days in both groups (Wilcoxon p = 0.507). Multivariable logistic regression confirmed that there was no association between prophylaxis and 30-day SSOs (adjusted odds ratio [aOR] 1.28; 95% CI 0.58-2.82; p = 0.543) or SSIs (aOR 1.92; 95% CI 0.18-20.31; p = 0.588). In the subgroup analyses, no stratum could be identified in which prophylaxis significantly reduced SSOs. There was only a non-significant trend toward higher SSO rates in obese patients (Grade II/III) who received prophylaxis (30.4% vs. 7.1%; OR 4.02; 95% CI 0.67-24.22).

In this propensity-score-matched cohort, the omission of perioperative antibiotic prophylaxis following rVHR is not associated with an increase in SSOs, SSIs, or LOS. In conjunction with the very low overall SSI rate (approx. 2%), these findings prompt a necessary shift toward a more differentiated approach to routine antibiotics in this setting. We emphasize, however, that this conclusion must not be extrapolated to laparoscopic intraperitoneal onlay mesh (IPOM) or to open repair, where the contamination profile and wound-healing risk differ fundamentally.