Management of ureteral calculi and medical expulsive therapy in emergency departments.

Abstract

Ureteral stones are a common problem in daily emergency department practice. Patients may be offered medical expulsive therapy (MET1) to facilitate stone expulsion and this should be offered as a treatment for patients with distal ureteral calculi, who are amenable to waiting management. Emergency department clinicians and family practitioners are often in the front line regarding the diagnosis and treatment of symptomatic nephrolithiasis and this commentary is dedicated to them because their decisions directly influence the outcome of the acute stone episode and appropriate referral patterns.
The aim of this systematic review and meta-analysis was to understand the role of MET in the treatment of obstructing ureteral calculi. A bibliographic search covering the period from January 1980 to March 2010 was conducted in PubMed, MEDLINE and EMBASE. The searches were restricted to publications in English. This analysis is based on the 21 studies that fulfilled the predefined inclusion criteria.
A metaregression analysis of expulsion time showed a statistically significant advantage in the experimental group, in which the mean expulsion time was 6.2 days compared to 10.3 days in controls. The treatment effect on expulsion rate (P = 0.53) was partially lost as the size of the stones decreased because of the high spontaneous expulsion rate of small stones and the expulsion time was not influenced by pharmacological treatment (P = 0.76) if the stone size was smaller than 5 mm. Analysis of the tamsulosin database. A total of 1283 participants were included in the 17 studies. These studies showed that compared to standard therapy or placebo, tamsulosin had significant benefits, being associated with both a higher stone expulsion rate (P < 0.001) and reduction of the expulsion time (P = 0.02). Reductions in the need for analgesic therapy, hospitalization and surgery are also shown. Analysis of the nifedipine database. The number of participants in each trial ranged from 25 to 70. Compared to standard therapy, the use of nifedipine significantly improved the spontaneous stone expulsion rate (P < 0.001). The mean expulsion time was slightly, but not statistically significantly, different (P = 0.19) between the treatment and control groups. A possible benefit of nifedipine, in terms of significantly reducing the doses of analgesics required, was reported in three studies. There was no difference between the tamsulosin- and nifedipine-treated groups with regard to expulsion time (P = 0.17) or expulsion rate (P = 0.79).
Despite all its advantages, MET is rarely used, representing a failure of the translation of medical science into practice. These data raise concerns not only about the quality of care of patients who could benefit from resolution of stones without anaesthetic and surgical risks but also with regard to potential cost savings. MET should be offered as a treatment for patients with distal ureteral calculi who are amenable to a waiting management.