Yoeri Bemelmans

Safety and efficacy of outpatient hip and knee arthroplasty 95 7 Introduction As a result of successful fast-track surgery pathways and its continuous optimisation, hip and knee arthroplasty are increasingly performed on an outpatient basis. These day-care surgery pathways are being designed to discharge patients home without an overnight stay in the hospital [1]. This might benefit patients in terms of possible reduced risk for hospital-acquired infections, starting early rehabilitation in their own home environment, and the possibility of enhanced patient participation and improved satisfaction. Besides, there is potential to reduce the economic burden on the healthcare systems, as the demand for hip and knee arthroplasties is increasing internationally [2,3,4,5,6]. When implementing a new treatment (e.g. an outpatient joint arthroplasty (OJA) pathway following hip and knee arthroplasty), it is paramount to ensure the quality of the provided care and safety of patients. Acceptable clinical outcomes, in terms of complications and readmission rates, were found for both hip and (partial) knee arthroplasty in previous systematic reviews [7,8,9,10]. These systematic reviews mainly consisted of observational case series, which included a selected group of patients. Patients selected for OJA are generally expected to be healthier compared with the average population undergoing hip or knee arthroplasty. However, even in an unselected group of patients, similar results were found [11, 12]. When comparing outcomes on OJA, variation in used definitions in the literature has to be accounted for. Some authors defined outpatient as a length of stay (LOS) less than 24 h, whereas others defined outpatient as hospital discharge on the day of surgery. Also large national registry databases (e.g. the NSQIP) which are frequently used in OJA research, use a controversial outpatient definition. A study by Bovonratwet et al. reported that only 11–12% of patients who were registered as outpatients were actually discharged on the day of surgery, because regulations in the USA allow these patients to stay more than 1 night in hospital under observation status. Off all studies reporting on the NSQIP data, different variables are used to indicatie OJA: (1) the “outpatient status variable”; and (2) the “LOS (=0) variable” (which appears to be more accurate). To ensure clarity and uniformity, we agree with Vehmeyer et al. [13] to reserve the term “outpatient joint arthroplasty” solely for patients who are discharged to their own home on the day of surgery and who do not have an overnight stay at either the hospital or another non-home facility. The purpose of this systematic reviewwas to study the safety and efficacy of outpatient pathways compared with standard inpatient recovery pathways following hip and (partial) knee arthroplasty, accounting for the abovementioned definitional differences