The association of neuraxial versus general anesthesia with inpatient admission following arthroscopic knee surgery

Study objective: Arthroscopic knee procedures are increasingly being performed in an outpatient setting. Appropriate intraoperative anesthesia is vital to prevent complications such as unanticipated hospital admission. We examined differences in complications between general (GA) vs neuraxial anesthesia (NA) as the primary anesthetic for patients undergoing arthroscopic knee procedures. Design: This was a retrospective cohort study. We queried the National Surgical Quality Improvement Program for arthroscopic knee procedures performed between 2007 and 2016. We compared postoperative complication rates between propensity-matched cohorts (NA vs GA). The anesthesia groups were matched based on age, race, BMI, gender, diabetes, smoking history, COPD, CHF, functional status, HTN, ASA class, steroid use, bleeding disorder history, and readmission status. Univariable and multivariable logistic regression were used to compare factors associated with inpatient admission defined - as hospital length of stay > 1 day. Patients: A total of 57,494 patients were included - 55,257 GA and 2237 NA patients. Main results: Among the matched cohorts, NA patients were significantly more likely to be admitted to the hospital postoperatively (p < 0.001). Neuraxial anesthesia (OR 5.93, 95% CI 4.90-7.21) use was also significant in the final multivariable regression model for inpatient admission. Additional significant predictors for inpatient admission included history of bleeding disorder (OR 5.44, 95% CI 2.14-12.76), Asian race (OR 6.47, 95% CI 4.90-8.56), COPD (OR 3.10, 95% CI 1.94-4.82), diabetes (OR 1.90, 95% CI 1.43-2.49), and increased operation time (OR 3.01, 95% CI 2.69-3.37). Conclusions: NA was significantly associated with inpatient admission following knee arthroscopy. Further research should focus on examining the reason for this association and methods to reduce inpatient admission for patients undergoing arthroscopic knee procedures using neuraxial anesthesia.