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Postoperative urinary retention (POUR) refers to the inability to pass any urine despite a full bladder after surgery. It is a common complaint, occurring in up to 70% of surgical patients depending on the type of surgery. Individuals undergoing perineal, gynecologic, anorectal, inguinal, and lower urinary tract surgeries are at an increased risk for POUR. Additional risk factors include older age, male sex, prolonged surgery, spinal anesthesia, and early removal of urinary catheters.

The development of POUR has been associated with several negative outcomes, including pain, urinary tract infection (UTI), bladder dysfunction, kidney damage, increased length of hospital stays, elevated costs, and the need for additional surgeries. Urethral catheterization is the mainstay of management of POUR; however, catheterization alone can also increase the risk for UTI and extend hospital stays. For these reasons, pharmacotherapeutic approaches to prevention of POUR are needed.

At least eight clinical trials evaluating the safety and effectiveness of tamsulosin, a selective alpha-1 adrenergic receptor blocker, for prevention of POUR in male patients undergoing different types of surgery have been published to date. The results of these studies have been generally consistent, with six of the eight trials reporting a statistically significant reduction in the risk for POUR with tamsulosin versus placebo. The type of surgical patient and tamsulosin regimen studied in each of the identified trials are listed in the Table below. Three observational studies also have found positive outcomes associated with the use of tamsulosin in surgical settings.

Table. Characteristics of Clinical Research Assessing Tamsulosin Therapy for Prevention of POUR

Medical expulsive therapy using the alpha blocker tamsulosin does not aid passage of ureteral stones less than 9 mm in diameter, according to study findings published online in JAMA Internal Medicine.

In the double-blind STONE (Study of Tamsulosin for Urolithiasis in the Emergency Department) trial, investigators randomly assigned 512 emergency department patients (mean age 41; 27% female; 23% non-white) to 0.4 mg daily tamsulosin or placebo for 28 days. Stone passage rate did not differ significantly between groups (50% tamsulosin vs 47% placebo), Andrew Meltzer, MD, of George Washington University in Washington DC, and colleagues reported. In addition, the investigators observed no significant between-group differences with respect to time to stone passage, return to work time, analgesic use, hospitalization, need for surgery, or repeat visit to the emergency department.

For the study, patients could have stones in any part of the ureter. Stone size, location, and passage were confirmed by computed tomography.

Current guidelines by the American Urological Association recommend alpha blockers for ureteral stones 10 mm or less in diameter.

References

Meltzer AC, Katzen Burrows P, Wolfson AB, et al. Effect of tamsulosin on passage of symptomatic ureteral stones. JAMA Intern Med. doi:10.1001/jamainternmed.2018.2259 [Published online June 18, 2018]

Dahm P and Hollingsworth JM. Medical expulsive therapy for ureteral stones—Stone Age medicine. JAMA Intern Med. [Published online June 18, 2018]

Treatment with an α1adrenoceptor antagonist, tamsulosin, is associated with increased dementia risk among patients with symptomatic benign prostatic hyperplasia (BPH) aged ≥65 years, according to a Medicare data analysis published in Pharmacoepidemiology Drug Safety.

Using Medicare data from 2006 to 2012, investigators obtained patient data for men ≥65 years who were actively taking tamsulosin (n=253,136). These patients were compared with propensity-score-matched patients who did not use BPH medications (n=180,926), as well as patients who used doxazosin (n=28,581), terazosin (n=23,858), alfuzosin (n=17,934), dutasteride (n=34,027), and finasteride (n=38,767). Investigators used International Classification of Diseases, Ninth Revision, diagnosis codes to determine and compare incident dementia rates between each group.

A greater number of men in the tamsulosin group had dementia at the median 19.8-month follow-up compared with men who were not taking BPH medications (31.3 vs 25.9 per 1000 person-years, respectively; hazard ratio [HR], 1.17; 95% CI, 1.14-1.21; P <.001). In addition, patients taking tamsulosin had a significantly higher dementia risk than those taking doxazosin (HR, 1.20; 95% CI, 1.12-1.28; P<.001), terazosin (HR, 1.11; 95% CI, 1.04-1.19; P =.002), alfuzosin (HR, 1.12; 95% CI, 1.03-1.22; P =.010), dutasteride (HR, 1.26; 95% CI, 1.19-1.34; P <.001), and finasteride (HR, 1.13; 95% CI, 1.07-1.19; P <.001).