Postoperative retention of urine: a prospective urodynamic study.

OBJECTIVE To investigate the cause of post-operative retention of urine in elderly men. DESIGN Prospective study. SETTING Northern General Hospital, Sheffield. PATIENTS 32 consecutive men (median age 73, range 55-85) referred to the urology department who were unable to pass urine either within 48 hours after operation and required catheterisation (23) or after removal of a catheter inserted at the initial operation (nine). INTERVENTION Intermittent self catheterisation. MAIN OUTCOME MEASURES Urological investigation by medium fill and voiding cystometry within four weeks after operation, and minimum follow up three months thereafter. RESULTS 6 patients resumed normal voiding before urodynamic assessment, three proceeded straight to prostatectomy, and one was unfit for self catheterisation. Of 22 men who underwent urodynamic investigation, only five had bladder outflow obstruction, who subsequently had successful prostatectomy; 15 showed either a low pressure-low flow system (seven) or complete detrusor failure (eight) and two showed pelvic parasympathetic nerve damage. With intermittent self catheterisation spontaneous voiding returned in all but one man within a median of 8 weeks (range 6-32 weeks). Recovery of bladder function took significantly longer in men with detrusor failure than in those with an underactive bladder (median 10 weeks (range 6-32 weeks) v median 8 weeks (range 6-8 weeks); p = 0.05). Three months later all patients had re-established their own normal voiding pattern with minimal residual urine on ultrasonography and satisfactory flow rates. CONCLUSIONS Postoperative urinary retention in elderly men is not an indication for prostatectomy; a normal pattern of micturition can be re-established by intermittent self catheterisation in most men.