Urinary Bladder Catheterization in Fast-track Hip and Knee Arthroplasty - What is the Optimal Bladder Volume? A Randomized, Controlled Study

Approximately 40 % of all patients undergoing fast-track total hip or knee arthroplasty needs intermittent bladder catheterization after surgery, as they are transient incapable of voluntary bladder emptying (postoperative urinary retention - POUR). The currently used interventional threshold for urinary bladder catheterization are a bladder volume of approximately 500 ml., but no evidence exists for this threshold. At the same time, the current knowledge suggest, that a bladder volume up to 1000 ml. for 2-4 hours are safe in humans, and as the use of urinary bladder catheterization are increasing the risk of complications, the investigators are hypothesizing that increasing the interventional threshold for urinary bladder catheterization after fast-track total hip or knee arthroplasty, will reduce the number of patients needing urinary bladder catheterization, without increasing the incidence of urological complications - including urinary tract infections.