1547. Does Length of Stay Impact Likelihood of Unplanned Readmissions Following Spine Surgery? Insights from a National Surgical Registry

Authors: Mohamad Bydon, MD, FAANS ; Anshit Goyal, MBBS; Elena Blaginykh, MD, MPH; Mohammed Alvi, MBBS; Panagiotis Kerezoudis, MD, MS (Rochester, MN)


Postoperative length of stay has been recently prioritized as a way to drive down healthcare costs. However, studies have shown that decreasing length of stay might be associated with increase in adverse outcomes. In this project, we sought to investigate the impact of length of stay on 30-day readmission after 4 common spine procedures using a national registry


We queried the ACS-NSQIP 2012-2016 for patients undergoing four most commonly performed spinal procedures: ACDF, Lumbar Discectomy, Lumbar Laminectomy and posterior lumbar fusion(PLF). Patients were grouped based on their length of stay into 1) <3 days, 2) 3 days, and 3) > 3 days. Univariate analysis and multivariable logistic regression were performed to assess the impact of hospital length of stay on unplanned readmission after adjusting for an array of patient factors.


A total of 91,102 patients, were included in the analysis. The median age of the study sample was 59 years with 50.5% males. Median length of stay varied by procedure: ACDF, Lumbar Discectomy: 1 day; Lumbar Laminectomy: 2 days, PLF: 3 days. Rate of unplanned readmission was 4.1% (3,678 patients) for all four spinal procedures[ACDF: 3.0% (n=525), Lumbar Discectomy: 3.7% (n=377), Lumbar Laminectomy: 4.4%(n=714), PLF: 4.5% (n=2062)]. Overall, LOS > 3 days was associated with an increased likelihood for unplanned readmission(OR: 1.26; CI: 1.14-1.38, Ref: LOS=3 days) while LOS< 3 days did not confer an increased risk(OR: 0.95; CI: 0.87-1.04, Ref: LOS=3 days). Further analyzing by each procedure, LOS>3 days was associated with higher odds of readmission following Lumbar Laminectomy(OR: 1.3; CI: 1.03-1.61, Ref: LOS=3 days) and PLF(OR: 1.23; CI: 1.1-1.38, Ref: LOS=3 days).


LOS>3 days following spine surgery might be associated with increased risk for unplanned 30-day readmissions, while a shorter length of stay appears to have no impact on odds of readmission.