John C Kubasiak, MD, MacKenzie D Landin, MD, Scott Schimpke, Jennifer Poirier, PhD, Jonathan Myers, MD, Keith Milikan, MD, Minh Luu, MD. Rush
Background: As the effort to reduce post-operative morbidity and mortality continues, the search for modifiable patient risk factors to reduce complications is ongoing. Tobacco use is associated with impaired wound healing but its effect on inguinal hernia repair has not been studied in a large population. An ACS-NSQIP dataset was used to evaluate the effect of tobacco use on outcomes of inguinal hernia repairs.
Methods: The ACS-NSQIP dataset was queried for patients who underwent open or laparoscopic inguinal hernia repairs, by primary procedure CPT codes, between years 2009-2012. Tobacco use was registered as defined by the ACS-NSQIP, as both a current smoker (within the past 12 months) or as a history of smoking (having ever smoked). Univariate and multivariate analyses were used to investigate outcome variables for 30-day morbidity and mortality by type of operative intervention while adjusting for preoperative risk factors.
Results: During the study period, 90,162 patients underwent inguinal hernia repair. 76% of the cases were open compared to 24% laparoscopic. The population was overwhelmingly male, 91%, compared to 9% female. The average age of patients was 42.5 years. Of the available data (69% of patients included), 38.5% had never smoked. Of those who had smoked, 18% had smoked within the 12 months prior to surgery (current smokers). Their average number of pack years was 27.2 compared to 4.5 pack years for those who had not smoked 12 months prior to surgery (historical smokers). Current smokers and historical smokers were more likely to undergo an open repair than nonsmokers. There were statistically significant differences between age (p<2.2e-16), and procedure type (open vs. laparoscopic) (p=3.5e-15, p=1.73e-14) between current and historical smokers. Using Fisher’s exact test, historical smoking status was found to be significantly associated with a return to OR (p=0.010), pneumonia (p=0.0008) and infectious outcomes (p=0.02). When controlling for sex, type of surgery, and age, using logistic regression, historical and current smoking status was associated with reintubation, pneumonia and return to OR (all p<0.03).
Conclusion: Current smoking status is a modifiable risk for patients undergoing laparoscopic and open inguinal hernia repair. Failure to quit smoking prior to surgical repair is associated with complications like reintubation, pneumonia and return to OR.