Clinical Outcomes for Interval Appendectomy in the Treatment of Acute Appendicitis With an Appendiceal Abscess or Mass

Abstract

Introduction: The possibility of converting to an extended operation and the incidence of complications are said to be high in emergent surgery for acute appendicitis with an appendiceal abscess or mass. Recently clinical reports on ‘ Interval Appendectomy' (IA) for appendiceal abscess or mass are encountered, which comprises conservative therapy followed by elective appendectomy. Our hospital has employed IA since April, 2014. Here we make a presentation of our clinical outcomes for IA and discuss the efficacy of it. Methods: The indications for IA in our hospital are follows: 1) Abdominal CT shows an appendiceal mass or abscess (>1cm): 2) Abdominal examination does not reveal panperitonitis. In cases which satisfy our criteria, we plan to perform appendectomy 2-3 months after nonoperative treatment with antibiotics or percutaneous drainage. We employed this protocol, 14 cases, since April 2014 until March 2015. Also before designing this protocol, we performed emergent appendectomy (EA) for similar cases. Since January 2010 until April 2014, we experienced EA 11cases. We compared these two groups(IA 14 cases and EA 11 cases). Results: Conservative treatment was successful in 12 of the IA 14 patients (85.7%) with an average of 11 days of hospital stays. And in 2 patients, shifts to the emergent surgery were required because of uncontrolled infection. Between this IA 12 cases and EA 11 cases, we compared operation time, volume of bleeding, operative method, complications, total hospital stays and total hospital costs. In operation time (78.2minutes vs 149.5minutes; p=0.0019), volume of bleeding (4.92g vs 302.5g; p=0.0005), operative method (laparoscope=12 vs laparoscope/conversion to laparotomy/laparotomy=2/3/6; p < 0.0001, appendectomy=12 vs appendectomy/cecum partial resection/ileocecal resection=3/2/6; p=0.0002) and complications (SSI=1 vs SSI/ abscess formation/ileus=3/1/1; p=0.0368), IA were significantly superior. And also in total hospital stays (14.0days vs 12.7days; p=0.5712) and total hospital cost (9655.5dollars vs 11538.8dollars; p=0.1244), there were no statistic differences between IA and EA. Conclusion: 1)In IA cases, conversion to an extended operation was not seen and there were few complications. 2) We don't have longer hospital stays or higher total hospital cost in performing IA. For these reasons, we conclude that interval appendectomy is effective for acute appendicitis with an appendiceal abscess or mass.