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Case Scenario: A 49 year old man presents to the ED with his typical problem of renal colic.
Question:Is an alpha blocker safe and effective for the treatment of kidney stones?
Reference: Vincendeau et al. Tamsulosin Hydrochloride vs Placebo for Management of Distal Ureteral Stones. Arch Intern Med. 2010;170(22):20212027 PMID: 21149761
- Population: 129 adult patients with acute renal colic presenting to ED with stone size of 27mm.
- Exclusion criteria: Pregnant or breastfeeding women, patients receiving alpha or beta-blockers, those with transient hypotension, those with liver impairment, and those requiring a surgical procedure because of infection or continuation of pain after medical treatment were excluded. Patients with spontaneous passage before randomization were also excluded.
- Intervention: Tamsulosin 0.4mg OD
- Control: Placebo
- Outcome: Time to stone expulsion from inclusion in study up to 42 days.
Authors’ Conclusions: “Although well tolerated, a daily administration of 0.4 mg of tamsulosin did not accelerate the expulsion of distal ureteral stones in patients with ureteral colic”
BEEM Commentary: Renal colic is a very common presentation to the ED. Several studies have demonstrated the use of alpha-blockers to help pass stones faster and with less pain. These trials had some limitations due to publication bias and non masking of small cohorts of patients.
This study appears to be a well designed, multicenter, randomized, double-blind trial that shows tamsulosin was well tolerated but did not speed up the passage of distal uretral stones. However, the fact that the investigators only recruited 129 patients from 6 french hospitals over five years and then took another four years to get it published suggest the quality of the study might not be what it appears.
As with some similar studies, these results suggest tamsulosin does not work. A sytematic review is currently underway by the Cochrane Collaboration to help resolve this controversy. Zhu Y et al. Alpha-blockers as medical expulsive therapy for ureteral stones. Cochrane Database of Systematic Reviews 2010, Issue 5. Art. No.:CD008509. DOI:10.1002/14651858.CD008509.
EBM Point: They “p” all over this paper (it was a urology paper after all). A better statistical test would have been to do a relative risk reduction or number needed to treat (NNT) analysis.
BEEM Bottom Line: Tamsulosin 0.4 mg OD does not seem to work for renal colic beyond the placebo effect.
Remember to be skeptical of anything you learn, even if you heard it on the Skeptics’ Guide to Emergency medicine.