Inhalant exposure and outcomes after inguinal hernia repair: cigarette, cannabis, and vaping effects by surgical approach.

BACKGROUND

Inguinal hernia repair (IHR) is among the most commonly performed surgical procedures worldwide. Successful postoperative recovery can often depend on effective wound healing, durable fibrocollagenous repair, and appropriate mesh integration, processes known to be adversely affected by cigarette smoking. Nicotine and other tobacco-related toxins can increase the risk of wound and mesh-related complications. The impact of other inhaled substances, including cannabis and electronic vaping products, often perceived as less harmful alternatives, remains poorly characterized. This study evaluates the comparative impact of cannabis use, cigarette smoking, and vaping, as well as surgical approach (open versus laparoscopic), on postoperative outcomes following IHR.

METHODS

A retrospective cohort study was conducted using the TriNetX global research database. Adult patients (aged ≥ 18 years) undergoing first-time inguinal hernia repair were identified and stratified into four mutually exclusive exposure cohorts: cigarette smoking (ICD-10 F17.21), electronic vaping (U07.0 and F17.20), cannabis use (F12 series, RxNorm 1976, CPT 80349), and a control group with no documented inhalant exposure. Patients were matched 1:1 using propensity score matching separately within each surgical approach stratum. Primary outcomes were 30-day surgical site infection (SSI) and wound complications. Secondary outcomes were long-term operative hernia recurrence and mesh explantation (6 months to 5 years). Subgroup analyses compared laparoscopic versus open repair within each exposure group.

RESULTS

After 1:1 propensity score matching, baseline characteristics were well-balanced across all cohorts. In the 30-day postoperative period, cigarette smoking was associated with a significantly higher risk of wound complications following laparoscopic repair (RR 1.97; p = 0.0008) and open repair (RR 1.77; p = 0.0003). SSI was not significantly elevated in any exposure group. Cannabis use and vaping demonstrated no statistically significant increase in SSI or wound complications. Compared to open repair, laparoscopic repair was associated with lower rates of SSI (RR 0.46; p = 0.0011) and wound complication (RR = 0.61; p = 0.0017) in smokers. Operative recurrence (6 months-5 years) was significantly increased only after open repair in cigarette (342 vs. 265 events; RR 1.29) and cannabis (68 vs. 43 events; RR 1.58) users.

CONCLUSION

These findings suggest that inhalants may pose exposure-specific risks to postoperative inguinal hernia outcomes. Among cigarette users, laparoscopic repair was associated with lower rates of surgical site infection and wound complications than open repair, suggesting that operative approach may help mitigate smoking-related early wound risk. These findings support preoperative cessation counseling for optimizing post-operative outcomes.