Incidence of and Risk Factors for Ileus Following Spine Surgery

Background: The purpose of this study was to determine the incidence of postoperative ileus (POI) after spine surgery and to identify risk factors for its development. Methods: A retrospective database study was performed between 2019 and 2021. A database of all patients who underwent spine surgery was searched, and patients who developed clinical and radiographic evidence of POI were identified. Demographic characteristics, perioperative data including opioid consumption, ambulation through postoperative day 1, surgical positioning, medical history, and surgical history were obtained and compared to examine risk factors for developing POI. Results: A total of 10,666 consecutive patients were identified who underwent cervical, thoracic, thoracolumbar, lumbar, or lumbosacral surgery with or without fusion. No patients were excluded from this study. The overall incidence of POI after spine surgery was 1.63%. POI was associated with a significantly greater mean length of stay of 7.6 +/- 5.0 days compared with 2.9 +/- 2.9 days in the overall cohort (p < 0.001). A history of ileus (odds ratio [OR], 21.13; p < 0.001) and a history of constipation (OR, 33.19; p < 0.001) were also associated with an increased rate of POI compared with patients without these conditions. Postoperatively, patients who developed POI had decreased early ambulation distance through postoperative day 1 at 14.8 m compared with patients who did not develop POI at 31.4 m (p < 0.001). Total postoperative opioid consumption was significantly higher (p < 0.001) in the POI group (330.3 morphine equivalent dose [MED]) than in the group without POI (174.5 MED). Lastly, patients who underwent fusion (p < 0.001), were positioned in a supine or lateral position (p = 0.03) (indicators of anterior or lateral approaches), had thoracolumbar or lumbar surgery (p = 0.01), or had multiple positions during the surgical procedure (p < 0.001) had a significantly higher risk of POI than those who did not. Conclusions: The overall incidence of POI after all spine surgery is low. Several nonmodifiable predictors of POI include prior ileus, constipation, hepatitis, and prostatectomy. Multiple surgical factors increased the risk of POI, including supine positioning, surgery with the patient in multiple positions, and fusion. POI was associated with decreased early ambulation and increased opioid usage. Strategies should be implemented to maximize early ambulation and decrease opioid usage perioperatively.