Introduction: Smoking has been shown to increase the risk of pseudoarthrosis after fusion and has been linked to complications after spinal surgery. However, it is unclear to what extent smoking status has on the development on wound infections in patients undergoing posterior lumbar fusion.
Methods: Patients were identified by CPT (Current Procedural Terminology) code in the American College of Surgeon’s National Surgical Quality Improvement Program (ACS-NSQIP) databasePatients were divided into those with and without current smoking history. Univariate (chi-square and Student t-test) analysis was performed on demographics, comorbidities and operative variables (including procedure subtypes). Only variables with p<0.2 were evaluated for inclusion in the final step-wise multivariate logistic regression to determine if smoking was an independent risk factor for wound complications [Superficial Surgical Site infection (SSI), Deep SSI, Wound Dehiscence, Organ space SSI]. Level of significance was set at p=0.05.
Results: Smokers were likely to be younger and male (50.18% vs. 43.38%, p<0.0001) than non-smokers. Patients who smoked were less likely to be diabetic (12.44% vs. 18.61%, p<0.0001) and also less likely to be identified as obese class III (6.47% vs. 7.69%, p<0.0001) than nonsmokers. Smokers were observed to have a significantly increased rate of pulmonary, cardiac and peripheral vascular disease than their non-smoking counterparts. Despite some increased comorbidities in smokers, ASA = 3 was more commonly seen in nonsmokers than smokers (47.04% vs. 42.84%, p=0.006). Prior to undergoing surgery, non-smokers were more likely to have a dependent functional status than smokers (4.39 vs. 2.98%, p=0.020). Multivariate logistic regression did not show smoking to be an independent predictor of wound complication [Odds Ratio (OR)=1.00, p=0.994)].
Conclusions: Smoking is not an independent predictor of surgical site infection when adjusted for other risk factors
Patient Care: Understanding the risk that smoking poses on posterior lumbar fusion surgery will help better stratify patients by risk prior to surgery.
Learning Objectives: By the conclusion of this session, participants should be able to understand the risks of smoking on posterior lumbar fusion.