Impact of Smoking Status on Long-term Postoperative Wound Dehiscence and Infection Following Robotic-assisted Spine Surgery

Introduction: Smoking is a well-documented risk factor for wound complications after spine surgery, but its effect on robotic-assisted cases remains to be explored. This study aims to evaluate the effect of smoking on long-term postoperative wound complications in robot-assisted spine surgery.

Methods: Patients undergoing robotic-assisted spine surgery from 2018—2022 were retrospectively identified and categorized according to smoking status, defined as current, former, and non-smoker. Primary outcomes were 1-year postoperative wound dehiscence and infection, with secondary analyses of intraoperative complications, comorbidities, and demographic factors. Risk factors for wound complications were identified using two predictive algorithms: XGBoost classifier and logistic regression. These models were evaluated through Receiver Operating Characteristic (ROC) analysis, with Shapley additive explanations (SHAP) applied to the best-performing model for feature importance.

Results: Of 503 patients identified, 47 (9%) were current smokers, 198 (39%) were former smokers, and 258 (51%) were non-smokers. The non-smoker cohort was predominantly female (61%, p=0.002) compared to former (44%) and current smokers (51%). Mean ages were 52 ± 12 years (current), 64 ± 12 years (former), and 61 ± 14 years (non-smokers). Current and former smokers had higher rates of chronic pulmonary disease (p < 0.001), mild liver disease (p < 0.0001), and higher Charlson Comorbidity Index (CCI) scores (p=0.049). Immediate postoperative complications, such as extremity edema (p=0.031) and septic shock (p=0.045), were more common among smokers. There were 12 (2.4%) cases of wound infection and 19 (3.8%) cases of dehiscence in total. Both predictive models demonstrated an AUC of 0.97, with favorable ROC curve profiles. After applying SHAP, smoking status was identified as fifth most significant predictor of wound dehiscence (after sex, age, number of screws placed, and diabetic status) and third most significant predictor of wound infection (after number of screws placed and age).

Conclusion : While smoking status is significantly associated with long-term wound complications after robot-assisted spine surgery, factors like age and number of screws placed must also be considered. These results emphasize the necessity for targeted preoperative counseling and risk stratification to improve surgical outcomes.