Preoperative Risk Factors for, and Incidence of Delayed Surgery in Elective Primary Total Knee Arthroplasty After Hospital Admission: The ACS-NSQIP

Background: Approximately 600,000 total knee arthroplasties (TKA) are performed every year in the United States and the number of procedures has increased substantially every year. These demands may further strain the government, insurers, and patients struggling with increasing healthcare spending. A delay in proceeding to surgery after hospital admission may affect the overall healthcare costs. To our knowledge, the current literature has not addressed the incidence of, and preoperative risk factors for, a surgical delay in TKA. Methods: The ACS-NSQIP 2011 database was reviewed to identify patients undergoing elective primary total knee arthroplasty (TKA) using the Current Procedural Terminology (CPT) code 27447. 14,881 cases were no delay in proceeding to surgery after hospital admission while 139 cases were delayed for TKA. Risk factors or comorbidities contributing to surgical delay in TKA were identified. A univariate analysis of all patient parameters was conducted to measure the difference between the two cohorts. Finally, a multivariate logistic regression analysis was then conducted to identify risk factors or comorbidities for surgical delay. Results: There were 139 cases of surgical delay in TKA (0.93%). Congestive heart failure (P = 0.017), bleeding disorder (P <0.0001), sepsis (P <0.0001), a prior operation in the past 30 days (P <0.0001), dependent functional status (P <0.0001), ASA class 3 (P = 0.046), and hematocrit <38% (P <0.0001) were independent risk factors for a surgical delay. Postoperative medical complication (2.2% vs 0.8%, P < 0.0001) in surgical delay was significantly higher than non-delayed cohort. Conclusion: The optimization of preoperative modifiable risk factors appears to be one of the best strategies to reduce delayed surgery and therefore costs in TKA.