Yoeri Bemelmans

Chapter 5 62 Materials andmethods This retrospective analysis included all patients who underwent elective unilateral primary total hip (THA), total knee (TKA), or unicompartmental knee (UKA) arthroplasty in a fast-track pathway between June 2014 and May 2015 in the Zuyderland Medical Center (Sittard-Geleen, the Netherlands). Patients were excluded from analysis in case of incomplete data registration, preoperative bladder volume >250 ml, and therefore placement of an indwelling catheter prior to surgery, preexisting usage of bladder catheterization, and/or patients who underwent arthroplasty surgery in an outpatient pathway. A total of 638 patients were analysed after application of the exclusion criteria (Fig. 1). A urinary bladder management protocol was used for the prevention of POUR by using an ultrasound bladder scanner (BladderScan® BVI 9400; VerathonMedical Europe BV, the Netherlands), based on the available literature [2, 3, 14, 18, 28] and the expert opinion of the hospital urologists (Fig. 2). Figure 1. Selection of patients. Total primary joint arthroplasty n=803 -Hip arthroplasty; n=381 (47%) -Knee arthroplasty; n=422 (53%) Excluded n=165 (21%) -Outpatient surgery; n=66 (8%) -Preoperative bladder volume >250ml; n=31 (4%) -Incomplete data; n=68 (9%) Analysed n=638 (79%) -THA; n=322 (40%) -TKA; n=302 (37%) -UKA; n=14 (2%) Pre ‑ , peri ‑ , and postoperative treatment Bladder volumesweremonitoredpreoperatively after voiding todetect a possible urinary retention>250ml, whichhas been found as a risk factor for POUR [3]. In case of >250ml of urinary retentionpreoperative after spontaneous voiding, indwelling catheterwas placed prior to surgery [27]. When indwelling catheter was used, it was removed the next day. All nurses were trained in using the bladder scanner and were familiar with the online available bladder scan protocol (Fig. 2). All surgeries were performed by seven experienced arthroplasty surgeons. Patients were operated under spinal or