Alpha blockers prior to removal of a catheter for acute urinary retention in adult men
Abstract
Background
Acute urinary retention is a urological emergency in men and requires urgent catheterisation. Any intervention which aims at increasing the rate of a successful trial without a catheter following an acute urinary retention episode would be considered potentially beneficial. Alpha blockers relax prostatic smooth muscle cells thereby decreasing the resistance to urinary flow and by doing so improve urinary symptoms.
Objectives
To assess the effects of alpha blockers on successful resumption of micturition following removal of a urethral urinary catheter after an episode of acute urinary retention in men.
Search methods
We searched the Cochrane Incontinence Group Specialised Register (11 February 2009) 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
Both 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. Both review authors extracted independently, cross‐checked and processed the data as described in the Cochrane Collaboration Handbook (Higgins 2008).
Main results
Five randomised clinical trials were eligible for inclusion in this review. All five trials compared alpha blockers versus placebo. In four trials alpha blockers were used between 24 to 72 hours (in one study up to a maximum of eight days) before trial without a catheter (TWOC); in one trial alpha blockers were used for eight days prior to trial without a catheter. Four trials tested alfuzosin and one trial tested tamsulosin. Four trials favoured alpha blockers and one trial favoured placebo. Overall rates of successful TWOC tended to favour alpha blockers over placebo. This was statistically significant (RR 1.39, 95% CI 1.18 to 1.64) irrespective of the alpha blocker used (alfuzosin: RR 1.31, 95% CI 1.10 to 1.56; tamsulosin: RR 1.86, 95% CI 1.17 to 2.97).
With regard to causing fewer vasodilatation‐related side effects (for example hypotension, dizziness), two studies favoured placebo and one favoured alpha blockers. Overall side effects were low for both placebo and alpha blockers. Failure rates were high and mainly caused by the need for re‐catheterisation rather than vasodilatation‐related side effects.
Authors' conclusions
The limited available evidence suggests that alpha blockers increase success rates of TWOC. Alpha blocker side effects are low and comparable to placebo. It is uncertain whether alpha blockers reduce the risk of recurrent urinary retention and need for prostate surgery. The cost effectiveness and recommended duration of alpha blocker treatment after successful TWOC remains unknown. There are a lack of internationally agreed outcome measures for what constitutes successful TWOC. This makes meta‐analysis difficult. More randomised clinical trials are needed to address these issues.
PICOs
Plain language summary
Alpha blocker treatment for men to increase chances to have urinary catheter successfully removed
Acute urinary retention in men is a medical emergency characterised by the sudden and often painful inability to pass urine. There are many known causes including prostate obstruction (because of enlargement of the prostate or cancer), urethral strictures, urine infection, constipation and neurological conditions. A narrow drainage tube (urinary catheter) is temporarily inserted into the bladder through the penis to allow drainage of urine. Once the catheter is removed, some men fail to pass urine and need to be re‐catheterised. In these men, continued use of catheters or prostate surgery are the standard treatment options. Catheters are associated with risks such as infection and can affect quality of life. Measures for increasing the rate of successful catheter removal, that is enabling patients to urinate spontaneously again, are therefore potentially beneficial. Alpha blockers (for example tamsulosin, alfuzosin) are a group of drugs known to have positive effects on urinary symptoms such as poor urinary flow. It is believed that their relaxing effect on the prostate may also increase the chance to void again after catheter removal. This review evaluated the evidence available to support this practice.
In five clinical trials men were either given a sugar tablet (placebo, inactive drug) or alpha blockers for one to three days (and in one study up to a maximum of eight days) before the catheter was removed. Neither patients nor doctors knew which type of tablet was given, to prevent the bias in reporting the results. The results suggested that alpha blocker treatment increased the chances of successful catheter removal and resumption of normal voiding although the overall scientific evidence available to support this was limited. Two different alpha blockers were tested (tamsulosin and alfuzosin). Their results were similar. Side effects caused by alpha blockers were few and comparable to placebo treatment. They included lack of ejaculation, dizziness, low blood pressure, fainting, sleepiness, feeling unwell and headache.
There was not enough evidence to say whether alpha blockers also reduce the risk of suffering another (recurrent) episode of urinary retention after successful catheter removal or whether they reduce the need for future surgery on the prostate. It is therefore unclear whether or for how long alpha blocker treatment should be continued after successful catheter removal and whether the costs of alpha blocker treatment in such situations are justified. Further research is needed to answer these questions.
