Time from surgery end to discharge following total knee arthroplasty: implications for same day discharge.

Background: Understanding the average time from surgery to discharge is important to successfully and strategically schedule cases planned for same day discharge (SDD) for total knee arthroplasty (TKA). The purpose of this study was to (1) evaluate the average time to discharge following unilateral TKA performed in a community hospital and (2) describe patient characteristics and peri-operative factors that may impact SDD.

Methods: This retrospective review included 75 patients having achieved SDD following unilateral TKA between March 2017 and September 2021 at a high-volume multi-specialty community hospital. Time to discharge was calculated from end of surgery, defined as completion of dressing application, to physical discharge from the hospital. Time surgery completed and association with time of discharge was also examined. Pearson's correlations were performed to evaluate the relationship between total time to discharge and patient demographics.

Results: The average age for all patients was 66.6 ± 10.9 years (Range: 38 to 86) and average BMI of 29.9 ± 5.6 kg/m (Range: 20.4 to 46.3). The average time to discharge was 5.8 ± 1.8 h (range: 2.2 to 10.5 h). Time to discharge was significantly longer for patients finishing surgery prior to noon (6.0 ± 1.8 h), than after noon (4.8 ± 1.4 h, p = 0.046). Total time to discharge was not correlated with age (r = 0.018, p = 0.881) or BMI (r=-0.158, p = 0.178), but was negatively correlated with surgical start time (r=-0.196, p = 0.094).

Conclusion: An average of six hours was required to achieve SDD following unilateral TKA performed in a community hospital. The time required for SDD was not found to be related to intrinsic patient factors but more likely due to extrinsic factors associated with time of scheduled surgery. To improve success of SDD, focus should be placed on the development of efficient discharge pathways rather than unchangeable intrinsic patient characteristics.