BACKGROUND: Historically, the negative appendectomy rate (NAR) for patients operated on for acute appendicitis (AA) has exceeded 20%. We sought to define the current NAR with increased use of computed tomography (CT) and laparoscopy. METHODS: Records of 1425 consecutive patients undergoing appendectomy for suspicion of AA during the past 7 years at a single institution were reviewed. The NAR was calculated and compared with earlier data from this institution (1995-1999). Statistical methods included the Fisher exact test and the Student t test; differences of P < .05 were considered statistically significant. RESULTS: The overall NAR was 7.65% compared to 16.3% over the period 1995-1999 (P = .0001), without a change in the perforation rate. Concurrently, the rate of preoperative CT increased from 32% to 95%. CT was associated with a lesser NAR only among adult females (7.6% vs 20.8%, P = .005) but not among adult males or children. No difference in NAR was noted in comparing laparoscopic and open appendectomy. Patients without AA had a greater mean duration of symptoms and lower white blood cell count at presentation than those with AA. Most patients undergoing negative appendectomy had a CT, and more than 50% had CT interpretations that were positive for, or could not exclude, AA. CONCLUSIONS: The NAR in our hospital has decreased progressively to approximately 5%. Although preoperative CT is used in almost all patients, it is only associated with a lesser NAR among adult females. False-positive CTs may contribute to the residual NAR, and further data are needed to determine whether subgroups of male or pediatric patients benefit from preoperative CT.
BACKGROUND: Historically, the negative appendectomy rate (NAR) for patients operated on for acute appendicitis (AA) has exceeded 20%. We sought to define the current NAR with increased use of computed tomography (CT) and laparoscopy. METHODS: Records of 1425 consecutive patients undergoing appendectomy for suspicion of AA during the past 7 years at a single institution were reviewed. The NAR was calculated and compared with earlier data from this institution (1995-1999). Statistical methods included the Fisher exact test and the Student t test; differences of P < .05 were considered statistically significant. RESULTS: The overall NAR was 7.65% compared to 16.3% over the period 1995-1999 (P = .0001), without a change in the perforation rate. Concurrently, the rate of preoperative CT increased from 32% to 95%. CT was associated with a lesser NAR only among adult females (7.6% vs 20.8%, P = .005) but not among adult males or children. No difference in NAR was noted in comparing laparoscopic and open appendectomy. Patients without AA had a greater mean duration of symptoms and lower white blood cell count at presentation than those with AA. Most patients undergoing negative appendectomy had a CT, and more than 50% had CT interpretations that were positive for, or could not exclude, AA. CONCLUSIONS: The NAR in our hospital has decreased progressively to approximately 5%. Although preoperative CT is used in almost all patients, it is only associated with a lesser NAR among adult females. False-positive CTs may contribute to the residual NAR, and further data are needed to determine whether subgroups of male or pediatric patients benefit from preoperative CT.
Authors: Juliane Liese; Thomas M Halbinger; Frank Ulrich; Wolf O Bechstein; Christoph W Strey Journal: Langenbecks Arch Surg Date: 2014-03-16 Impact factor: 3.445
Authors: Jenneke T H Hamminga; H Sijbrand Hofker; Paul M A Broens; Philip M Kluin; Erik Heineman; Jan Willem Haveman Journal: Surg Endosc Date: 2012-10-17 Impact factor: 4.584
Authors: Frederick Thurston Drake; Michael G Florence; Morris G Johnson; Gregory J Jurkovich; Steve Kwon; Zeila Schmidt; Richard C Thirlby; David R Flum Journal: Ann Surg Date: 2012-10 Impact factor: 12.969