Outcomes following outpatient anterior cervical discectomy and fusion for the treatment of myelopathy.

Introduction: Anterior cervical discectomy and fusion (ACDF) is a commonly performed procedure for the treatment of degenerative cervical disease. With continued increase in U.S. healthcare expenditure, surgeons have begun to more closely examine the benefits of performing ACDF in an outpatient setting to increase efficiency, reduce the overall financial burden on patients/providers, and provide streamlined care for these patients. The purpose of this study was to analyze outcomes following outpatient ACDF for the treatment of myelopathy.

Methods: 14,490 patients who had undergone ACDF for myelopathy from 2010 to 2018 were included in this retrospective study, of which 2956 (20.40%) patients were considered to have undergone outpatient surgery. Pearson chi-squared tests and Fischer's Exact Tests were used to analyze differences in categorical variables of demographics, preoperative comorbidities, and postoperative complications, while Mann-Whitney-U-Tests were used to compare mean values of continuous variables. Coarsened-exact-matching (CEM) was implemented to control for baseline differences in demographics and comorbidities, and post-matching diagnostics included multivariate and univariate imbalance measure assessment. Outcomes were compared between the CEM-matched inpatient and outpatients ACDF cohorts.

Results: Upon CEM-matching (L1-statistic <0.001), the outpatient cohort (n = 2610, 25.13%) demonstrated significantly lower rates of any complication (p < 0.001), minor complications (p = 0.001), urinary tract infections (p = 0.029), blood transfusions (p < 0.001), major complications (p < 0.001), deep incisional surgical site infections (p = 0.017), ventilator dependence (p = 0.027), cardiac arrest (p = 0.028), unplanned reoperations (p = 0.001), and mortality (p = 0.006) in the 30-day postoperative period when compared to inpatient controls (n = 7774, 74.87%).

Conclusion: ACDF has been a target amongst spinal procedures as a prime candidate for outpatient surgery. However, no previous reports have described complication rates and perioperative parameters in the sub-population of outpatient ACDF patients with myelopathy. In addition to shorter times from admission to operating room, operative time, and LOS, our study also demonstrated lower rates of major and overall complications in outpatient ACDF's for myelopathy in comparison to their inpatient counterparts. Performing ACDF's for myelopathy in an outpatient setting may help to curb costs, improve outcomes, and serve as a valuable learning resource for graduate medical education with rapid turnovers and shorter operative times.