Impact of imaging tests on the negative appendectomy rate

Introduction: Negative appendectomies and perforated appendectomies have traditionally been quality indicators in surgery. The aim of this study is to analyze the emergency appendectomies in our hospital regarding the use of imaging tests and a review of the literature to analyze the quality of diagnosis in acute appendicitis. Material and methods: Retrospective study including all patients operated on for suspected acute appendicitis at a single institution for one year (2007). Data gathered from histology and imaging tests reports. Analysis of the histology results, imaging test used and its diagnostic accuracy. Comparison with quality levels published in the international literature. Results: A total of 394 patients were included in the study, the overall rate of negative appendectomy was 9.6%. Abdominal ultrasound (AU) was performed on 54.6% of patients and abdominal CT-scan on 10.2% of them, and 4.2% of the patients had both tests. AU positive predictive value was 82%. CT-scan positive predictive value was 97%. Conclusion: The negative appendectomy rate (9.6%) in our centre shows values lower than the published ones in historical series but superior to the one published recently in the USA. The use of imaging tests in our hospital is lower than the one published in the USA, although similar to data reported in other European countries. (C) 2009 SECA. Published by Elsevier Espana, S.L. All rights reserved.