Prevention of postherniorrhaphy urinary retention with prazosin

Urinary retention that necessitates catheterization after herniorrhaphy is a well known, but usually ignored, situation. Increased sympathetic activit y resulting from surgery may be the contributing factor. Blockade of ct rec eptors in the bladder neck and urethral sphinchter may prevent postoperativ e urinary retention. In this prospective placebo-controlled study, the effi cacy of prazosin in preventing postoperative urinary retention after hernio rrhaphy was investigated in 156 patients. Patients were randomized into two groups. Patients in Group I (control) were given placebo orally 12 hours b efore surgery, just before surgery, and 12 and 24 hours after surgery. In G roup II, 1 mg of prazosin was given in the same manner of placebo. Nine of 84 patients (10.8%) in the prazosin group and 18 of 72 patients (25%) in th e placebo group developed urinary retention. Catheterization was required i n only 3 patients (3.5%) in the prazosin group compared to 10 patients (13. 8%) in placebo-treated group (P < 0.05). In conclusion, prophylactic use of prazosin after herniorrhaphy significantly reduced the incidence of urinar y retention and catheterization.