Association Between Intravenous to Oral Opioid Transition Time and Length of Hospital Stay After Posterior Spinal Fusion for Adolescent Idiopathic Scoliosis

Background: Transitioning from intravenous (IV) to oral opioids after posterior spinal fusion (PSF) for adolescent idiopathic scoliosis (AIS) is necessary during the postoperative course. However, few studies have assessed the effects of longer transition times on hospital length of stay (LOS). This study investigated the impact of longer IV to oral opioid transition times on LOS after PSF for AIS.Methods: The medical records of 129 adolescents (10-18 years old) with AIS undergoing multilevel PSF at a major academic institution from 2013 to 2020 were reviewed. Patients were categorized by IV to oral opioid transition time: normal (& LE;2 days) vs prolonged (& GE;3 days). Patient demographics, comorbidities, deformity characteristics, intraoperative variables, postoperative complications, and LOS were assessed. Multivariate analyses were used to determine odds ratios for risk-adjusted extended LOS.Results: Of the 129 study patients, 29.5% (n = 38) had prolonged IV to oral transitions. Demographics and comorbidities were similar between the cohorts. The major curve degree (P = 0.762) and median (interquartile range) levels fused (P = 0.447) were similar between cohorts, but procedure time was significantly longer in the prolonged cohort (normal: 6.6 & PLUSMN; 1.2 hours vs prolonged: 7.2 & PLUSMN; 1.3 hours, P = 0.009). Postoperative complication rates were similar between the cohorts. Patients with prolonged transitions had significantly longer LOS (normal: 4.6 & PLUSMN; 1.3 days vs prolonged: 5.1 & PLUSMN; 0.8 days, P < 0.001) but similar discharge disposition (P = 0.722) and 30 -day readmission rates (P > 0.99). On univariate analysis, transition time was significantly associated with extended LOS (OR: 2.0, 95% CI [0.9, 4.6], P = 0.014), but this assocation was not significant on multivariate analysis (adjusted OR: 2.1, 95% CI [1.3, 4.8], P = 0.062).Conclusions: Longer postoperative IV to oral opioid transitions after PSF for AIS may have implications for hospital LOS.Level of Evidence: 3.