Analysis of the air/water channels of gastrointestinal endoscopies as a risk factor for the transmission of microorganisms among patients

Abstract

Background: For the effective reprocessing of gastrointestinal endoscopes, contaminants must be removed from the entire surface. However, these devices have long and narrow channels that can make this process difficult.

Methods: In this cross-sectional study, the staff assigned to reprocess gastroscopes and colonoscopes in 37 services located throughout Brazil completed a questionnaire regarding reprocessing practices geared toward the channels in these devices. In addition, samples from these air/water channels were collected for microbiological analysis.

Results: Contamination was detected in 71.8% (28/39) of the samples obtained from the air/water channels of colonoscopes, and in 70% (42/60) of the samples from the air/water channels of gastroscopes. The median microbial load was 1,800 colony-forming units (CFU)/mL in the colonoscopes and 750 CFU/mL in the gastroscopes. The main microorganisms isolated from the air/water channels of gastroscopes were Pseudomonas aeruginosa (26.4%), Escherichia coli (18.9%), and Acinetobacter baumannii (9.4%), and those isolated from the colonoscopes included P aeruginosa (46.4%), A baumannii (14.3%), and Klebsiella pneumoniae (10.7%), among others. The possible causes of the contamination of these devices included the failure to fill these channels with cleaning solution, lack of friction during cleansing, and inadequate rinsing.

Conclusion: The contamination of the air/water channels did in fact represent a risk for the transmission of microorganisms during gastrointestinal endoscopy exams, possibly related to the inadequate reprocessing of these channels.