Out of Hours Percutaneous Nephrostomy

Abstract

This apparently depressing survey should not lead us into huddles of self-doubt and insecurity. Findings of poor out-of-hours provision are unarguable, but how to ensure clinical competence is a thorny issue and the discussion should be treated with caution. Riddell et al. [ 1 Riddell A.M. Charig M.J. A survey of current practice in out of hours percutaneous nephrostomy insertion in the United Kingdom. Clin Radiol. 2002; 57: 1067-1069 Abstract Full Text PDF PubMed Scopus (20) Google Scholar ] mention a figure of 10–20 nephrostomies per year to maintain competence, derived from a study by Lee et al. [ 2 Lee W.J. Mond D.J. Patel M. Pillari G.P. Emergency percutaneous nephrostomy: technical success based on level of operator experience. J Vasc Interv Radiol. 1994; 5: 327-330 Abstract Full Text PDF PubMed Scopus (42) Google Scholar ]. However, Lee's study is flawed. First, they used a crude nephrostomy technique—anatomical landmarks were used to opacify the system—and under-used ultrasound (US). This may account for why those who performed less than 20 cases/year had a higher repeat rate. These radiologists also performed only 28/169 (16.5%) of all cases in the study, another study flaw/bias. In fact, all Lee et al. concluded is that those who perform <20 cases/year have a higher repeat nephrostomy rate. Initial success and major complication rates—the two more important performance indicators—were not related, but the study was under-powered. Clearly, these data are not secure enough for UK radiologists to accept <20/year as a fixed or even notional bench mark. This should be understood as, by repetition, this figure may come to be trusted. For example, it was used uncritically by the Royal College of Radiologists (RCR) for a pilot audit—as can be seen on RCR website—but I presume will not form the basis of any general guidelines that the College may or may not produce. At the moment, only the American College of Radiologists [ 3 American College of RadiologistsStandards for the Performance of Percutaneous Nephrostomy. American College of Radiologists, Reston, VA2001 Google Scholar ] has produced formal nephrostomy standards. Correctly, they do not mention any figure/year to maintain competence, and simply recommend that department success and complication rates should be monitored and maintained above certain thresholds, which they do recommend.