The role of alpha blockers prior to removal of urethral catheter for acute urinary retention in men.

BACKGROUND: Acute urinary retention is a urological emergency in men and requires urgent catheterisation. Any intervention which aims at improving urinary symptoms following an acute urinary retention episode could be potentially beneficial. Alpha blockers relax prostatic smooth muscle cells thereby decreasing the resistance to urinary flow and by doing so could improve urinary symptoms.

OBJECTIVES: To assess the effectiveness of alpha blockers on successful resumption of micturition following removal of a urethral urinary catheter after an episode of acute urinary retention in men. In the absence of internationally agreed outcome measures for the success of a trial without catheter, success was defined as the return to satisfactory voiding without need for re-catheterisation within 24 hours.

SEARCH METHODS: We searched the Cochrane Incontinence Group Specialised Trials Register, which contains trials identified from the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, MEDLINE in process, and handsearching of journals and conference proceedings (searched 9 October 2013), CENTRAL (2013, Issue 5) (searched 5 June 2013), MEDLINE 1946 to May Week 4 2013, MEDLINE in Process (covering to 3 June 2013), EMBASE Classic and EMBASE 1947 to 2013 Week 22 (all searched 4 June 2013) and the reference lists of relevant articles. No language or other restrictions were imposed on the searches.

SELECTION CRITERIA: Only randomised and quasi-randomised clinical trials of alpha blockers for trial without a urethral catheter following an episode of acute urinary retention in men were included.

DATA COLLECTION AND ANALYSIS: Two review authors independently examined all the citations and abstracts derived from the search strategy. Any disagreement about trial selection and inclusion was resolved by discussion. A third independent judgement was sought where disagreement persisted. Two review authors extracted independently, cross-checked and processed the data as described in the Cochrane Handbook for Systematic Reviews of Intervention. Quality of evidence of the critical outcomes was assessed by adopting the GRADE approach.

MAIN RESULTS: Nine randomised clinical trials were included in this review. Eight trials compared alpha blockers versus placebo (five trials tested alfuzosin and two trials tested tamsulosin, one trial tested both alfuzosin and tamsulosin, one trial tested silodosin) and one trial compared an alpha blocker (doxazosin) versus no treatment. Trial without catheter was performed after treatment with the drug for one to three days in seven trials and for eight and 32 days in two other trials respectively. There was moderate quality evidence to suggest that the rate of successful trial without catheter favoured alpha blockers over placebo ( 366/608, 60.2%, of men using an alpha blocker were able to void spontaneously after catheter removal compared with 185/486, 38.1%, using placebo, risk ratio (RR) 1.55, 95% confidence interval (CI) 1.36 to 1.76). The incidence of recurrent acute urinary retention was lower in groups treated with an alpha blocker (RR 0.69, 95% CI 0.60 to 0.79). This evidence was of moderate quality and was statistically significant for alfuzosin, tamsulosin and silodosin, though not for doxazosin. Of the trials mentioning adverse effects (for example, postural hypotension, dizziness), there was not enough information to detect statistically significant differences between the groups (RR 1.19, 95% CI 0.75 to 1.89) and the evidence was of low quality. Overall, adverse effect rates were low for both placebo and alpha blockers and, for example, vasodilatation-related adverse effects did not often result in discontinuation.

AUTHORS' CONCLUSIONS: There was some evidence to suggest that alpha blockers increase the success rates of trial without catheter, and the incidence of adverse effects was low. There was some evidence of a decreased incidence of acute urinary retention. The need for further surgery, cost effectiveness and recommended duration of alpha blocker treatment after successful trial without catheter remain unknown as these were not reported by any trial. There is a lack of internationally agreed outcome measures for what constitutes successful trial without catheter. This makes meta-analysis difficult. Large, well-designed controlled trials, which use the recommendations set out in the CONSORT statement, and include clinically important outcome measures, are required.