The effect of tobacco use on outcomes of laparoscopic and open inguinal hernia repairs: a review of the NSQIP dataset

Abstract

Background: As the effort to reduce postoperative 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, in two ways: current smoking (within the past 12 months), or history of smoking (having ever smoked). Univariate and multivariate analyses were used to investigate outcome variables for 30-day morbidity by type of smoking status, 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), 38.5 % had a history of smoking. 18 % had smoked within the 12 months prior to surgery (current smokers). Their average number of pack years was 27.2 (SD 24.0) compared to 4.5 pack years (SD 14.7) for those who had not smoked 12 months prior to surgery (historical smokers). Using Fisher's exact test, having ever smoked was found to be significantly associated with pneumonia (p = 0.0008) and return to the operating room (p = 0.010). This relationship held when preoperative variables were controlled for using logistic regression (pneumonia, p = 0.002; return to the operating room, p = 0.002). When preoperative variables were controlled for and logistic regression was performed for current smokers, there was also a significant association with pneumonia (p = 0.005) and return to the operating room (p = 0.01).

Conclusion: Current smoking status is a modifiable risk of patients undergoing laparoscopic and open inguinal hernia repair. Failure to quit smoking prior to surgical repair is associated with complications like pneumonia and return to the operating room.

Keywords: Inguinal hernia; NSQIP; Postoperative complications; Smoking.