Is There an Association Between Operative Time and Length-of-Stay after Shoulder Arthroplasty?

Understanding and reducing lengths-of-stay (LOS) after orthopedic procedures has become essential with the implementation of bundled payment reimbursement models. Previous small cohort investigations have identified risk factors for increased LOS after primary shoulder arthroplasty, such as renal insufficiency, cardiac disease, American Society of Anesthesiologists (ASA) classification, and operative time >174 minutes. The National Surgical Quality Improvement Program (NSQIP) database was queried for all primary shoulder arthroplasty cases (Current Procedural Terminology [CPT] code 23472) between 2008 and 2016 yielding 14,449 total patients. Univariate analysis using linear regression and independent sample t-tests were used to determine associations between LOS and the study variables. The outcome of interest was the association between operative time and LOS using multivariate regression models. Overall, the mean (±standard deviation) LOS was 2 (±2) days. Simple linear regression demonstrated age, gender, and operative time had significant positive correlations with length of hospital stay (p<0.001). Multivariate analysis showed that after adjusting for patient factors (age, gender, BMI, and ASA), longer operative times had significant associations with longer hospital stays (β = 0.109, SE <0.001, p value <0.001). The results demonstrate LOS is associated with age, gender and operative time. Operative time had the greatest effect on LOS after multivariate analysis. This study highlights the importance of operating room efficiency on healthcare quality and economics after shoulder arthroplasty.