P88. Influence of time of discharge and length of stay on 30-day outcomes after elective lumbar spine surgery

Abstract

<h3>BACKGROUND CONTEXT</h3> As health system reimbursements are restructured through bundled care and value-based payments, hospitals face increasing pressures to increase patient throughput while enhancing patient safety. Among many efforts, appropriate time of discharge (TOD) after medical and surgical admissions has received increasing scrutiny. Prior research suggests that earlier discharges after medical admissions result in higher likelihood of readmission and health care expenditures following discharge. Data specific to elective spine surgical admissions, however, are lacking. We hypothesize that likelihood of readmission or representation within 30 days is not affected by earlier time of discharge after surgical admissions for these procedures. <h3>METHODS</h3> We performed a retrospective cohort analysis on data collected between April 1, 2015, and December 1, 2021 from a single, large academic center following elective posterior, non-endoscopic lumbar laminectomy, discectomy, microdiscectomy, foraminotomy and/or facetectomy without fusion. The primary outcome measure of interest was readmission or emergency department (ED) re-presentation within 30 days following discharge. Analyses accounted for multiple patient and procedure-level covariates including, but not limited to, race, insurance status, socioeconomic status, procedure day of week, procedure length, use of tubular retractor system, evaluation by physical (PT) and occupational therapy (OT) and discharge disposition to location other than home. Discrete variables were normalized. Multivariable logistic regression analysis was performed to assess if covariates were independently predictive of 30-day readmission or ED representation. Poisson regression was used to assess the relationship between length of stay (LOS) in midnights and discharge disposition. <h3>RESULTS</h3> A total of 779 patients who had elective lumbar spine surgery were included, with a mean age of 66 (±15), median procedure duration of 94 minutes (IQR: 72, 131), and median LOS in midnights of 1 (IQR: 1,2). Results from multivariable logistic regression analysis demonstrated that time of discharge (OR 1.18 95% CI 0.92-1.52, p=0.192) and LOS (OR 1.13, 95% CI 0.86-1.50, p=0.374) were not associated with an increased risk of readmission or re-presentation to the ED. Patients discharged on a weekend were more likely to represent to the hospital (OR 2.14, 95% CI 1.11-4.12, p=0.023). Risk of readmission or ED re-presentation was not significantly associated with other sociodemographic or procedural characteristics. Patients operated on by a surgeon with less than one year of experience (OR 0.40, 95% CI 0.17-0.94, p=0.035) or two to five years of experience (OR 0.48, 95% CI 0.23-0.98, p=0.045), evaluated by physical therapy (OR 0.20, 95% CI 0.12-0.32, p < 0.001), or discharged on a weekend (OR 0.51, 95% CI 0.28-0.93, p=0.028) were less likely to be discharged before noon. Patients discharged not to home were associated with a significantly longer LOS (IRR 2.05, 95% CI 1.79-2.35, p < 0.001). <h3>CONCLUSIONS</h3> Patients undergoing elective lumbar spine surgery were not at higher risk of readmission or return to the ED with earlier TOD or length of stay following elective lumbar spine surgery but were at higher risk if discharged on a weekend. Patients operated on by less experienced surgeons, discharged on weekends, or evaluated by physical therapy while inpatient were all at decreased odds of discharge before noon. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.