sign in sign up
<<
Home , Urinary retention

and Prostatic Diseases (2004) 7, 32–37 & 2004 Nature Publishing Group All rights reserved 1365-7852/04 $25.00 www.nature.com/pcan Review Acute Urinary Retention: a review of the aetiology and management

K Thomas1*, K Chow1 & RS Kirby1 1Urology Department, St George’s Hospital, London, UK

Acute retention of urine (AUR) is a common urological emergency characterised by a sudden inability to pass urine associated with lower . In recent years, the natural history and incidence of AUR has become better understood, however, further research into methods to prevent it and evaluation of the impact an episode of AUR has on the patient is required. This review provides an overview of the current management of AUR in men and the impact of the condition on patients’ quality of life. and Prostatic Diseases (2004) 7, 32–37. doi:10.1038/sj.pcan.4500700

Keywords: acute urinary retention; catheterisation; quality of life; benign prostatic hyperplasia

Introduction urin* in the title, limited to English language. From this search 465 records were identified. Further information Acute retention of urine (AUR) is a common urological was gathered from related references within the articles condition that often presents as an emergency with a identified and by hand searching recent abstracts at sudden inability to pass urine associated with lower urological scientific meetings. Of the 465 records identi- abdominal pain.1,2 The reported incidence varies between fied, 121 were case reports of unusual cases of AUR. studies from a 4 to 73% 10-year risk of AUR.3,4 One of the most common causes of acute urinary retention is benign prostatic hyperplasia (BPH), which with an ageing popu- Aetiology lation is likely to increase. It may be anticipated, therefore, The precise aetiological factors responsible for the that the incidence of AUR will also rise, unless preventa- 5 development of AUR are still unproven but the main tive measures are taken for the treatment of BPH. mechanisms postulated are (Table 1): The immediate management of this condition varies between institutions, but usually involves placement of a (1) increased resistance to flow of urine via mechanical urinary either, supra-pubic or urethral, medical or dynamic means8 therapy and either immediate admission to hospital or (2) interruption of sensory innervation or motor supply discharge home with outpatient follow-up.6,7 In recent to detrusor muscle9 years, the natural history and incidence of AUR has (3) overdistension of the bladder.1,2,10 become better understood, however, further research into methods to prevent it and evaluation of the impact Increased resistance to the flow of urine can occur an episode of AUR has on the patient is required. This secondary to a mechanical obstruction such as stricture review provides an overview of the current management or prostatic enlargement, or less commonly an increase of AUR in men and the impact of the condition on in either the smooth or striated muscle tone. Interruption patients’ quality of life. of the sensory or motor nerve supply to the detrusor muscle is caused by a variety of pathologies, for example, spinal cord lesion (traumatic or neurological), diabetic Search methods neuropathy, cerebrovascular accident. Overdistension of the bladder is seen after a general anaesthetic or a large A Medline search using databases from 1966 to 2003 was fluid challenge (often with alcohol). Postoperative AUR conducted using the words acute AND retention AND occurs during a prolonged procedure with the patient uncatheterised and in men who have had mild symp- toms of BPH preoperatively. It is also exacerbated by the *Correspondence: K Thomas, Department, Ashford Hospital, Middlesex, UK. E-mail: [email protected] use of , concomitant administra- Received 28 August 2001; revised 9 October 2003; accepted 20 October tion and the generalised increase in alpha-adrenergic 11 2003 activity that exists after . Acute urinary retention K Thomas et al 33 Table 1 Pathogenesis of AUR Table 2 Potential neuromodulators in the bladder Pathogenesis Example Acetylcholine (ACh) Noradrenaline (NAd) Increased resistance to flow Prostatic hyperplasia Vasoactive polypeptide (VIP) Neuropeptide Y (NYP) Detrusor sphincter dysynergia Substance P (SP) Enkephaline Interruption of sensory or motor Spinal cord lesion Somatostatin innervation to detrusor Cerebrovascular lesion Nitric oxide (NO) mellitus

Overdistension Postoperative analgesia Table 3 Risk factors for AUR Large volume alcohol Risk factor Parameter Relative risk Confidence consumption interval

Agea 470 y 7.8 3.7–16.4 A scientific explanation for the clinically observed Symptomsa IPSS47 3.2 1.9–5.4 aetiologies has been explored, with the following Prostate volumea 430 ml 3.0 1.0–9.0 a processes thought to be involved; Flow rate o12 ml/s 3.9 2.3–6.6 1. prostatic infarction.12–14 Risk factor Parameter Area under the 2. neurotransmitter modulation.15,16 curve 17,18 3. stromal epithelial tissue ratio. PSAb 42.5 0.70 Transition zone 40.65 0.924 Prostatic infarction has been discussed as a potential c cause for AUR by several authors.12–14 Spiro et al index evaluated the potential role of prostatic infarction as a aJacobsen et al.19 bRoehrborn et al.22 cause of AUR by examining open speci- c 25 mens of 200 patients. The first 100 patients had large Kurita et al. and AUR, while the second group of 100 patients had elective surgery for BPH. In all, 85% of the The most comprehensive of these is the Olmstead AUR group had histological evidence prostatic infarction County trial, which identified a cohort of men in the compared with 3% of the elective group. It has also been general population aged between 40 and 79 y.19 Those proposed that the elevated prostate-specific antigen with previous history of prostatectomy, prostate cancer (PSA) found in patients with AUR is secondary to 14 or any other condition except benign prostatic hyperpla- prostatic infarction. sia were excluded from the study. The 2115 men Experimental work in animals has suggested that there recruited underwent an interview, completed a ques- may be multiple neuromodulators affecting the nerves 15,16 tionnaire and had their flow rate measured. Of these, 537 that supply the bladder and (Table 2). (25%) were randomly selected for a clinical examination, Reversible and irreversible changes are seen when PSA measurement and trans-rectal ultrasound (TRUS) of AUR is induced experimentally in animals. In particular, the prostate. The men were followed up for a median changes in the nonadrenergic, noncholinergic neuro- average of 50 months. The risk of AUR was shown to be transmitters have been reported in rats. It has been increased with age, from 1.6% risk at 5 y for men aged shown that if the episode of AUR is not relieved, cell 40–49 y to 10% for men aged between 70–79 y. The death in ganglia in the bladder wall can occur within 24 h symptom correlation was also found as men with and is well established by 48 h. moderate to severe symptoms had three times the risk A retrospective study in a small number of patients of AUR compared with those with none to mild (10) found that the ratio of stromal to epithelial tissue symptoms. In younger men, symptoms of double was decreased in patients with AUR compared with age- 17 voiding and stopping and starting appeared most matched controls. This finding was confirmed by significant. A single peak flow rate measure of another group, who conducted a prospective study of o12 ml/s correlated with a four times risk of AUR and the TURP specimens of 70 patients (35 with AUR and 35 a prostate volume 430 ml was associated with a three- with symptomatic BPH). The AUR group had a fold increase in risk. Potential limitations of this study significantly higher epithelial component 71%, compared 18 were the retrospective collection of follow-up data, the with the BPH group 60% (Po0.01). The cause for this ethnic and socio-economic status of the population observation is uncertain, but it may explain why studied, who were mostly white, middle class men. , which acts on the epithelial component, is Also, the age range of the men was below that of most effective in the prevention of AUR. patients admitted with acute retention in the UK and elsewhere.20 These factors mean that caution should be taken in extrapolating the findings to hospital practice Identification of risk factors elsewhere in the world. The risk factors discussed have also been identified in The exact aetiology of AUR is still unclear, however, other studies. In a population-based study of 6100 male there are studies that have identified risk factors for AUR health professionals aged between 45 and 82 y, it was in men and calculated the overall risk at 5–7/1000 year found that older age (470 y), moderate or severe lower (Table 3). urinary tract symptoms and the use of with

Prostate Cancer and Prostatic Diseases Acute urinary retention K Thomas et al

34 adrenergic or anticholinergic side effects significantly chance of successfully voiding after a TWOC.34 It has increased the risk of AUR. 21 The placebo arms of trials also been suggested that the use of an may of pharmaceutical treatments for BPH provide useful improve the success rate of a TWOC.35 epidemiological data and have demonstrated that PSA, prostate volume and symptom severity significantly 22–24 affect the risk of AUR. With increased use of Pharmacotherapy TRUS, the transition zone index (TZI ¼ transition zone volume/total prostate volume) has recently been There has been an increasing trend towards the use of suggested as a predictor for acute retention.25 drugs in both the prevention and treatment of AUR due to prostatic obstruction. The two main classes of drugs used are alpha blockers and 5 alpha-reductase inhibitors. Alpha blockers act by relaxing the smooth muscle in Treatment the bladder neck and prostate thereby decreasing the resistance to urinary flow. The potential role of alpha Catheterisation blockers in the treatment and prevention of AUR was first described 25 y ago.36 Since then different types of The initial management of AUR of urine is prompt relief alpha blockers have been produced and reported to have of retention and pain by catheterisation of the bladder. differing side effect profiles.37 The impact of some of This can be achieved via the urethral or supra-pubic these in the prevention of AUR has been compared route, each of which has its merits. Depending on the against placebo. A double-blind study of 2084 patients cause of the episode of AUR, local policy, the patient’s randomised to or placebo, reported no differ- physical condition and social circumstances they may be ence in the incidence of AUR in each group during the discharged with the catheter or admitted into hospital. 1 y follow-up period.38 In contrast, a study of 81 patients Urethral catheterisation is performed more commonly with AUR randomised to receive either alfuzosin or than supra-pubic because of concern regarding the placebo for 48 h prior to trial without catheter after 24 h potential complications of inserting a supra-pubic showed that those patients on alfuzosin had a signifi- catheter and that the personnel (ie accident and cantly increased chance of passing a trial without emergency staff, family practitioners) who first see catheter, 55 vs 28% (P ¼ 0.03). This effect was sustained patients with AUR are generally more familiar with this over 18 months of follow-up.39 method.26,27 A prospective study of 86 patients with Finasteride was until recently the only 5 alpha- AUR catheterised described a significantly lower inci- reductase inhibitor available, although now a newer dence of (18 vs 40%) and stricture agent, , is available.40,41 They act by selective formation (0 vs 16.7%) with supra-pubic vs urethral inhibition of 5 alpha-reductase responsible for the .28 It was also commented that trial without conversion of to .42 In a catheter was easier as it merely required clamping and large double-blind randomised placebo-controlled trial, unclamping of the supra-pubic catheter. The relatively 3040 men with moderate to severe lower urinary tract high stricture rate may be explained in part by the now symptoms and enlarged prostates were recruited.43 outdated use of latex catheters by this group; however, Over a 4 y period, they were treated daily with either the incidence is still likely to be higher than when the 5 mg finasteride or placebo. AUR developed in 99 (7%) supra-pubic route is used. The lower infection rate with men in the placebo group vs 42 (3%) in the finasteride supra-pubic catheterisation was also reported by a group. This represents over a 50% risk reduction for group, who randomised patients to urethral vs supra- developing AUR. However, because of the relatively pubic catheterisation.29 Also, it was noted that patients rarity of AUR, 15 men would have to be treated for 4 y to found the supra-pubic catheter was more comfortable avoid one episode of AUR. Similar reductions in the risk and easier to manage. Despite these findings the majority of events such as heart attack or occur with statins of patients with AUR are still managed with a urethral and antihypertensive .44 catheter, probably due to the continuing perception of A pooled analyses of three randomised trials compris- supra-pubic catheterisation as a potentially hazardous ing 4222 men with moderately symptomatic BPH treated procedure.30 with either finasteride or placebo for 2 y reported 81 A novel suggestion recently by one group is that episodes of AUR (24/2113 finasteride group, 57/2109 patients with AUR can be managed by clean intermittent placebo group).42 The hazard ratio for the occurrence of self-catheterisation (CISC).31 The authors found that the AUR was consistent among the studies with a 57% CISC group had a higher rate of spontaneous voiding (56 decrease in the hazard rate for patients treated with vs 25%) and lower infection rate (32 vs 75%) compared finasteride compared with placebo (Po0.001). with the indwelling catheter group. They concluded that patients found CISC acceptable and manageable and experienced fewer complications than those with an Combination therapy indwelling catheter do. An area of debate is the timing of the removal of a Prevention of the progression of BPH and in particular catheter (trial without catheter or TWOC). While some AUR has been studied using the combination of an have found no difference in success rates at 24 and 48 h,32 alpha-blocker and a 5 alpha-reductase inhibitor by others have suggested a benefit to waiting longer, several investigators.45–47 particularly in men with large residual volumes 41l.33 Two four-arm randomised placebo-controlled trials It has recently been suggested that prostate size 427.5 g, compared placebo with an alpha-blocker, finasteride and residual volume 41 l and age 475 y may reduce the combination therapy. Lepor et al used terazosin, whereas

Prostate Cancer and Prostatic Diseases Acute urinary retention K Thomas et al the Kirby group used doxazosin with similar results. traumatic. There have been a few studies, that have 35 Both groups found that the alpha-blocker was an looked at the impact of an episode of AUR on the patient, effective treatment for BPH and that over the study but this has remained a relatively neglected aspect of the period of 1 y, finasteride or combination therapy was no management of this condition. A recent retrospective more effective than an alpha-blocker alone. study of the management of patients with AUR in one The medical therapy of prostatic symptoms (MTOPS) surgeon’s practice over a 23 y period showed that 90% of study, a 5-y multicentre clinical trial evaluated whether patients were discharged home with a catheter to await the treatment with doxazosin and finasteride was more surgery.56 While at home 72% of patients experienced effective than using either drug alone in preventing the some complication, 69% found the catheter uncomfor- clinical progression of BPH.47 One of the endpoints for table and 65% found it inconvenient particularly with establishing the progression of BPH was AUR. The respect to finding adequate toilet facilities. Another combination therapy and finasteride significantly re- group prospectively evaluated the impact of discharging duced the long-term risk of AUR (crude rate per 100 patients with AUR home with a catheter by means of a patient years; placebo 0.6, doxazosin 0.4, finasteride 0.2, self-completion questionnaire.57 A total of 101 patients combination therapy 0.1). It was also noted that men in were seen with AUR and discharged home immediately the placebo group with higher baseline serum PSA, with a catheter. In all, 93% of the questionnaires were prostate volumes and ages and lower flow rate were completed. Unlike the previous group, the majority of significantly more likely to progress. patients (87%) did not find that the catheter limited their activities in anyway, although all of them had experi- enced at least one complication. The questionnaire used Surgical intervention was not a validated measure, however, it did show that despite having complications from the catheter most of At present, TURP still remains the ‘gold standard’ the patients still found having a catheter at home surgical treatment for patients with AUR. It reduces the acceptable. This study challenges the perception of most risk of developing AUR by a factor of eight.48 It is not clinicians that patients do not like having a catheter. without risk, however, and if patients who have had an Further work is required using validated questionnaires, episode of AUR have a TURP they are at a higher risk of a longer follow-up period and a broader evaluation of all per-operative complications.49 The National Prostatect- aspects of quality of life to define the impact of AUR and omy Audit found that men undergoing a TURP within having a catheter at home on patients. 30 days of an episode of AUR had an excess risk of death (relative risk 26.6, CI 2.5–7.6).20 With greater insight into the potential morbidity and occasional mortality associated with this procedure, Future research alternatives have been sought in the form of pharma- cotherapy and minimally invasive techniques. Most of There are various aspects of the management of AUR these new technologies are still based on the endoscopic that should be targeted in the future: removal or ablation of prostatic tissue; Electrovaporisa- (1) catheters tion, laser resection (holmium, Nd-YAG, ELAP, inter- (2) minimally invasive therapy stitial), interstitial radiofrequency (TUNA) and 50–52 (3) medical therapy microwave thermotherapy (TUMT). (4) quality of life Temporary or permanent urethral stents are available to keep the prostatic urethra open, but only provide Catheters are crucial in the management of AUR. The modest improvements in symptoms with a high ideal catheter material would be inert, malleable, incidence of complications such as migration, infection, biocompatible and be resistant to colonisation with encrustation, obstruction secondary to prostatic bacteria. In the future, newer technology in catheter ‘ingrowth’ and calculus formation.51 These problems design should make some of these properties possible have limited their current use to elderly infirm patients and, therefore, reduce some of the complications unfit for surgery.53,54 associated with having a catheter. Some patients may still be unable to void after a Evolution of minimally invasive techniques will make TURP.55 Urodynamic evaluation has not been shown to daycase treatment of BPH feasible, which should reduce predict this in patients under the age of 80 y as detrusor the time patients spend at home with a catheter failure may recover postoperatively.33 Therefore, urody- following an episode of AUR. namics are not recommended for routine preoperative As discussed previously, the use of combination evaluation in this age group. The presence of residual therapy for the treatment of BPH offers the opportunity volume 41500 ml, lack of detrusor instability, detrusor to prevent the progression of BPH and, therefore, pressure at maximum fill of o9 cm water and maximal episodes of AUR. Newer agents are under development detrusor pressure o28 cm water were all found to and may prove to be even more effective than the current predict treatment failure. formulations. An episode of AUR can have an adverse effect on a patient’s quality of life, which is further exacerbated by Quality of life delay in treatment and, prolonged period of catheterisa- tion. Awareness of the impact of AUR on a patient and As AUR usually involves an emergency admission to streamlining of the treatment of AUR so that prompt hospital and insertion of a catheter, it is perhaps not effective care is delivered would reduce the impact it has surprising that some patients may find the event on the patients, quality of life.

Prostate Cancer and Prostatic Diseases Acute urinary retention K Thomas et al 36 Discussion 21 Meigs JB et al. Incidence rates and risk factors for acute urinary retention: the health professionals follow up study. JUrol1999; Although AUR is an age-old condition, it remains a 162: 376–382. modern day management problem. As demonstrated by 22 Roehrborn CG et al. Serum prostate-speific antigen concentration Modi et al, treatment of patients with AUR may be is a powerful predictor of acute urinary retention and need for considered to be regressing rather than progressing.56 surgery in men with clinical benign prostatic hyperplasia. New pharmacological agents will emerge over then next Urology 1999; 53: 473–479. few years as will variations on TURP using modern 23 Lieber M et al. PSA is the strongest predictor of BPH related methods of tissue ablation. However, as clinicians we outcomes: results of a 4 year placebo controlled trial. JUrol1998; 159 must not lose sight of the impact of these treatments on : 104. 24 Rhodes T et al. Serum PSA levels predict acute urinary retention our patients. When introducing new therapies in the in 40-79 year old community men in Olmsted county. JUrol2000; future the effect of these on the patients’ quality of life in 161 (Suppl 4): Abstract 1118. addition to their clinical effectiveness must be evaluated 25 Kurita Y et al. Transition zone index as a risk factor for acute if we are to improve our management of this common urinary retention in benign prostatic hyperplasia. Urology 1998; and disturbing condition. 51: 595–600. 26 Allardice JT et al. Acute urinary retention: which catheter? Ann R Coll Surg Engl 1988; 70: 366–368. 27 Webb VJ, Booth CM. Cutting the cost of catheterisation for acute retention – a hospital or domiciliary procedure? Br J Urol 1995; References 76: 443–445. 28 Horgan AF, Prasad B, Waldron DJ, O’Sullivan DC. Acute urinary 1 Emberton M, Anson K. Acute urinary retention in men: an age retention. Comparison of supra-pubic and urethral catheteri- old problem. BMJ 1999; 318: 921–925. sation. Br J Urol 1992; 70: 149–151. 2 Choong S, Emberton M. Acute urinary retention. Br J Urol 2000; 29 Ischan J, Hunt DR. Suprapubic catheters: a comparison of 85: 186–201. suprapubic versus urethral catheters in the treatment of acute 3 Ball A, Feneley R, Abrahams P. The natural history of untreated urinary retention. Aust N Z Surg 1987; 57: 33–36. ‘‘prostatism’’. Br J Urol 1981; 53: 613–616. 30 Abrahams PH et al. Role of suprapubic catheterisation in the 4 Birkhoff J, Wiederhorn A, Hamilton M, Zinsser H. Natural retention of urine. J R Soc Med 1980; 73: 845–848. history of benign prostatic hypertrophy and acute urinary 31 Patel MI, Watts W, Grant A. The optimal form of urinary drainage retention. Urology 1976; 7: 48–52. after acute retention of urine. Br J Urol Int 2001; 88: 26–29. 5 McConnell JD. The long term effects of medical therapy on the 32 Taube M, Gajraj H. Trial without catheter following acute progression of BPH. Results from the MTOPS trial. J Urol 2002; retention of urine. Br J Urol 1989; 63: 180–182. 167, Abstract 1042. 33 Djavan B, Madersbacher S, Klinger C, Marberger M. Urody- 6 Beard R, Hindley R, Borley N, Cox C The management of acute namic assessment of patients with acute urinary retention: is urinary retention in the South Thames Region. South Thames Health Authorities Urology Audit, 2001. treatment failure after prostatectomy predictable? JUrol1997; 7 Higgins PM, Karia SJ, Mehta. The management of acute 158: 1829–1833. retention of urine. Br J Urol 1981; 53: 344–348. 34 Kumar V, Marr C, Bhuvangiri A, Irwin P. A prospective study of 8 Powell PH, Smith PJB, Feneley RCL. The identification of conservatively managed acute urinary retention: prostate size patients at risk from acute retention. Br J Urol 1980; 52: 520–522. matters. Br J Urol 2000; 86: 816–819. 9 Murray K, Massey A, Feneley RCL. Acute urinary retention—a 35 McNeill AS et al. Long term follow up following presentation urodynamic assessment. Br J Urol 1984; 56: 468–473. with first episode of acute urinary retention. JUrol2000; 163 10 Waterhouse N et al. Urinary retention after total hip replacement. (Suppl 4): Abstract 1366. A prospective study. J Bone Joint Surg Br 1987; 69: 64–66. 36 Caine M, Pfau A, Perlberg S. The use of alpha-adrenergic blockers 11 Raz S, Zeigler M, Caine M. Pharmacological receptors in the in benign prostatic obstruction. Br J Urol 1976; 48: 255–263. prostate. Br J Urol 1973; 45: 663. 37 De Mey. Alpha blockers for BPH: are there differences? Eur Urol 12 Spiro LH, Labay G, Orkin LA. Prostatic infarction. Role in acute 1999; 36: 52–63. urinary retention. Urology 1974; 3: 345–347. 38 Somers WJ, Mora MJ, Mason MF, Padley RJ. The natural history 13 Strachan JR, Corbishley CM, Shearer RJ. Post-operative retention of benign prostatic hypertrophy: incidence of urinary retention associated with acute prostatic infarction. Br J Urol 1993; 72: and significance of AUA symptom score. JUrol1996; 155: 586A 311–313. Abstract 1102. 14 McNeill SA et al. Serum PSA levels and histological changes 39 McNeill SA et al. Sustained-release alfuzosin and trial without associated with acute urinary retention. BJU Int 2000; 83 (Suppl 4): catheter after acute urinary retention: a prospective, placebo- Abstract P65. controlled trial. Br J Urol 1999; 84: 622–627. 15 Zhou Y, Ling EA. Effects of acute complete outlet obstruction on 40 Clark RV et al. Effective suppression of dihydrotestosterone the NADPH-diaphorase reactivity in the intra-mural ganglis of (DHT) by G1198745, a novel, dual 5 alpha-reductase inhibitor. the guinea pig : light and electron microscopic JUrol1999; 161, Abstract 1037. studies. JUrol1997; 158: 916–923. 41 Roehrborn CG et al. Efficacy and safety of a dual inhibitor of 5 16 Crowe R, Haven AJ, Burnstock G. Intramural neurons of the alpha reductase types 1 and 2 (dutasteride) in men with benign guinea pig urinary bladder: histochemical localisation of prostatic hyperplasia. Urology 2002; 60: 434–441. putative neurotransmitters in cultures and newborn animals. 42 Andersen JT et al. Finasteride significantly reduces acute urinary J Auton Nerv Syst 1986; 15: 319. retention and need for surgery in patients with symptomatic 17 Abehouse BS. Infarct of the prostate. JUrol1933; 3: 345–347. benign prostatic hyperplasia. Urology 1997; 49: 839–845. 18 Saboorian MH et al. Morphometric analysis of pathological 43 Mc Connell JD et al. The effect of finasteride on the risk of acute specimens in men undergoing prostate surgery for acute urinary retention and the need for surgical treatment among retention or symptoms of BPH only. JUrol1998; 159, Abstract men with benign prostatic enlargement. New Engl J Med 1998; 417. 338: 557–563. 19 Jacobsen SJ et al. Natural history of prostatism: risk factors for 44 Byington RP et al. Reduction in cardiovascular events during acute urinary retention. JUrol1997; 158: 481–487. pravastatin therapy. Pooled analysis of clinical events of the 20 Pickard R et al. The management of men with acute urinary Pravastatin Atherosclerosis Intervention Program. Circulation retention. Br J Urol 1998; 81: 712–720. 1995; 92: 2419–2425.

Prostate Cancer and Prostatic Diseases Acute urinary retention K Thomas et al 37 45 Lepor H et al. The efficacy of terazosin, finasteride or both in treatment of acute urinary retention from benign prostatic benign prostatic hypertrophy. N Engl J Med 1996; 335: 533–539. enlargement. Br J Urol Int 2000; 85: 83–86. 46 Kirby RS et al. Results of the PREDICT (prospective European 52 Makar AA, Thomas PJ, Fletcher MS, Harrison NW. Interstitial doxazosin and combination therapy) trial. JUrol1999; 161: radiofrequency therapy of the prostate in the management of Abstract 266. acute urinary retention. Br J Urol 1998; 81: 726–729. 47 McConnell JD. The long term effects of medical therapy on the 53 Perry MJ et al. Thermo-expandable intraprostatic stent in bladder progression of BPH. Results from the MTOPS trial. J Urol 2002; outlet obstruction: an 8 year study. Br J Urol Int 2002; 90: 216–223. 167: Abstract 1042. 54 Ogiste JS, Cooper K, Kaplan SA. Are stents still useful therapy 48 Wasson JH et al. A comparison of transurethral surgery with for benign prostatic hyperplasia? Curr Opin Urol 2003; 13: 51–57. watchful waiting for moderate symptoms of benign prostatic 55 Reynard JM, Shearer RJ. Failure to void after transurethral hyperplaia. N Engl J Med 1995; 332: 75–79. resection of the prostate and mode of presentation. Urology 1999; 49 Higgins PM, French ME, Chadalavada SR. Management of acute 53: 336–339. retention of urine: a reappraisal. Br J Urol 1990; 67: 365–368. 56 Modi P et al. A 23 year review of the management of acute 50 Kabalin JN et al. Holmium: YAG laser resection of prostate retention of urine: progressing or regressing? Ann R Coll Surg (HoLRP) for patients in urinary retention. J Endourol 1997; 11: Engl 2000; 82: 333–335. 291–293. 57 Khoubehi B, Watkin NA, Mee AD, Ogden CW. Morbidity and 51 Isotalo T et al. A pilot study of a bioabsorbable self-reinforced the impact on daily activities associated with catheter drainage poly L-lactic acid urethral stent combined with finasteride in the after acute urinary retention. Br J Urol Int 2000; 85: 1033–1036.

Prostate Cancer and Prostatic Diseases