What time of day should a urethral catheter be removed?

Patients who had undergone bladder neck surgery were randomized to having their urethral catheters removed either early in the morning or late at night. There was no difference in the incidence of urinary retention between these two groups of patients. However, patients who presented with acute urinary retention had a higher incidence of postoperative urinary retention. This study suggests that a urethral catheter may be safely removed in the evening without increasing the risk of urinary retention. There also seems to be no greater chance of the patient having to be recatheterized at an unsocial hour.