The incidence and risk factors for post-operative ileus after spinal fusion surgery: a multivariate analysis

Post-operative ileus is a recognized complication of surgery. Little is known about the incidence and risk factors for post-operative ileus following spinal fusion surgery. To report the incidence and to assess for independent risk factors of post-operative ileus after spinal fusion surgery.

Retrospective single-centre cohort study. Patients with prolonged or recurrent post-operative ileus were identified by review of hospital stay documentation. Patients with post-operative ileus were matched 1:2 to a control cohort without post-operative ileus. Uni and multi variate analyses were performed on demographic, comorbidity, surgical indication, medication, and peri-operative details to identify risk factors for post-operative ileus.

Two thousand six hundred and twenty five patients underwent spinal fusion surgery between January 2012 and December 2012. Forty nine patients with post-operative ileus were identified (1.9 %). Post-operative length of hospital stay was significantly longer for patients with post-operative ileus (9.3 ± 5.2 days), than control patients (5.5 ± 3.2 days) (p < 0.001). Independent risk factors were Lactated Ringers solution (aOR: 2.12, p < 0.001), 0.9 % NaCl solution (aOR: 2.82, p < 0.001), and intra-operative hydromorphone (aOR: 2.31, p < 0.01) and a history of gastro-oesophageal reflux (aOR: 4.86, p = 0.03). Albumin administration (aOR: 0.09, p < 0.01) was protective against post-operative ileus.

Post-operative ileus is multifactorial in origin, and this study identified intra-operative hydromorphone and post-operative crystalloid fluid administration ≥2 litres as independent risk factors for the development of ileus.