Ileus Following Adult Spinal Deformity Surgery.

Background: Postoperative ileus (POI) is a common complication after spine surgery, with particularly high rates after adult spinal deformity (ASD) surgery. Few studies have been conducted on predictors of POI following ASD surgery. The objective of this study was to determine risk factors for POI in patients undergoing ASD surgery and to determine association between POI and in-hospital mortality, length of stay, and total charges.

Methods: Data were obtained from the National (Nationwide) Inpatient Sample, years 2010-2014. Patients with ASD ≥26 years-old were selected using International Classification of Diseases, Ninth Revision, Clinical Modification codes. Multiple logistic and linear regressions were used.

Results: The analysis included 59,410 patients; 7.4% of patients had POI. On adjusted analysis, the following variables were associated with increased risk of POI: male sex (OR = 1.43; CI, 1.10-1.85), anterior surgical approach (OR = 1.78; CI, 1.22-2.60), ≥9 levels fused (OR = 1.84; CI, 1.24-2.73), electrolyte disorders (OR = 2.70; CI, 2.15-3.39), and pathologic weight loss (OR = 1.94; CI, 1.08-3.46). POI was associated with significantly longer length of stay (+39% [CI, 29%-51%]) and higher total charges (+23% [CI, 14%-31%]).

Conclusions: Risk factors for POI were identified. Length of stay was 2.9 days longer in patients with POI, and total charges were approximately $80,000 higher. These results may be applied clinically to identify patients at risk of POI and to address modifiable risk factors preoperatively. Future studies should be conducted with additional data to develop models capable of accurately predicting and preventing POI.