Retrospective single-surgeon study of 1123 consecutive cases of anterior cervical discectomy and fusion: a comparison of clinical outcome parameters, complication rates, and costs between outpatient and inpatient surgery groups, with a literature review

OBJECTIVE Outpatient anterior cervical discectomy and fusion (ACDF) is becoming more common and has been reported to offer advantages over inpatient procedures, including reducing nosocomial infections and costs, as well as improving patient satisfaction. The goal of this retrospective study was to evaluate and compare outcome parameters, complication rates, and costs between inpatient and outpatient ACDF cases performed by 1 surgeon at a single institution. METHODS In a retrospective study, the records of all patients who had undergone first-time ACDF performed by a single surgeon in the period from June 1, 2003, to January 31, 2016, were reviewed. Patients were categorized into 2 groups: those who had undergone ACDF as outpatients in a same-day surgical center and those who had undergone surgery in the hospital with a minimum 1-night stay. Outcomes for all patients were evaluated with respect to the following parameters: age, sex, length of stay, preoperative and postoperative pain (self-reported questionnaires), number of levels fused, fusion, and complications, as well as the presence of risk factors, such as an increased body mass index, smoking, and diabetes mellitus. RESULTS In total, 1123 patients were operated on, 485 (43%) men and 638 (57%) women, whose mean age was 50 years. The mean follow-up time was 25 months. Overall, 40.5% underwent 1-level surgery, 34.3% 2-level, 21.9% 3-level, and 3.2% 4-level. Only 5 patients had nonunion of vertebrae; thus, the fusion rate was 99.6%. Complications occurred in 40 patients (3.6%), with 9 having significant complications (0.8%). Five hundred sixty patients (49.9%) had same-day surgery, and 563 patients (50.1%) stayed overnight in the hospital. The inpatients were older, were more commonly male, and had a higher rate of diabetes. Smoking status did not influence the length of stay. Both groups had a statistically significant reduction in pain (expressed as a visual analog scale score) postoperatively with no significant difference between the groups. One- and 2-level surgeries were done significantly more often in the outpatient setting (p < 0.001). The complication rate was 4.1% in the outpatient group and 3.0% in the inpatient group; there was no statistically significant difference between the 2 groups (p = 0.339). Significantly more complications occurred with 3- and 4-level surgeries than with 1- and 2-level procedures (p < 0.001, chi-square test). The overall average inpatient cost for commercial insurance carriers was 26% higher than those for outpatient surgery. CONCLUSIONS Anterior cervical discectomy and fusion is safe for patients undergoing 1- or 2-level surgery, with a very significant rate of pain reduction and fusion and a low complication rate in both clinical settings. Outpatient and inpatient groups undergoing 3- or 4-level surgery had an increased risk of complications (compared with those undergoing 1- or 2-level surgery), with a negligible difference between the 2 groups. This finding suggests that these procedures can also be included as standard outpatient surgery. Comparable outcome parameters and the same complication rates between inpatient and outpatient groups support both operative environments.