Evaluation of microorganism colonization on laparoscopic instruments after surgery and following two different cleaning methods

Abstract

Background: An accurate cleaning, as the first step of reprocessing, would make the sterilization more effective, and protects healthcare providers and patients against infections. The present study aimed to compare the effect of two cleaning methods of conventional and the Association for the Advancement of Medical Instrumentation (AAMI) on the reduction of microorganism colonization on laparoscopic instruments. Methods: In this quasi-experimental study, 128 laparoscopic instruments was randomly divided into two groups of conventional and AAMI cleaning protocols. Sampling was done immediately after surgery and the cleaning process. The number and types of microorganisms which isolated from the Sabouraud Dextrose Agar, Blood Agar and MacConkey Agar media were determined. Findings: The total mean number of microorganisms isolated from instruments was 24 × 10 5 colony forming unit (CFU)/100 ml immediately after surgery. After cleaning process, it was reduced to 7.2 × 10 5 CFU/100 ml and 0.34 × 10 5 CFU/100 ml in conventional and AAMI groups, respectively. This reduction was significantly higher in the AAMI group than in the conventional cleaning group (P < 0.050). The most frequent type of the microorganisms isolated after surgery were as Escherichia coli (81.2), Pseudomonas aeroginosa (68.8), and Klebsiella spp. (57.8), respectively. Conclusion: Reduction of total mean number and frequency of the microorganisms after the cleaning process were higher in the AAMI group than in conventional group. Therefore, the AAMI method may prevent hospital-acquired infection, and is recommended as an effective cleaning method for laparoscopic instruments after surgery. © 2018, Isfahan University of Medical Sciences(IUMS). All rights reserved.