An Observational, Cross-Sectional Study to Investigate Whether Room Air Ventilators, Used in the Community Setting, Are Colonised by Potential Airborne Pathogens (IPAP Study)

TL;DR

This study found that 61% of ventilators used in the community had bacterial or fungal growth, with 7% containing potentially harmful pathogens.

Contribution

This is the largest study to investigate pathogen colonization in community-used ventilators.

Findings

61% of ventilators had bacterial or fungal growth.

7% of ventilators were contaminated with potentially pathogenic organisms.

Pathogens included Pseudomonas aeruginosa, Staphylococcus aureus, and Aspergillus sp.

Abstract

Background/Objectives: Long-term ventilation (LTV) is a widely used treatment for the management of patients with chronic respiratory failure. As use increases, it generates further questions about aspects of care. One issue is the potential risk of contamination within the device itself and the potential risk of respiratory tract infections in a subsequent user. Using an observational cross-sectional study design, the primary objective of this study was to identify whether airborne bacterial and fungal pathogens are present within a NIPPY 3+ (Breas Medical Ltd., Stratford Upon Avon, UK) room air ventilator following use in a community setting. Methods: Microbiological samples in the form of one single charcoal swab were taken from two specified areas of the device’s internal airflow pathway. Results: A total of 243 ventilators were sampled. A total of 215 ventilators with complete data collection were included in the study. A total of 84 (39%) were identified as having no growth and 131 (61%) were positive for bacterial and/or fungal growth. Overall, 307 organisms were grown from 131 ventilators ranging from 1 to 6 organisms per swab. Of the 215 ventilators screened, 15 (7%) grew organisms considered to be pathogenic. Well-established human pathogens were considered as ‘potentially pathogenic’ in this study due to the limitation of not obtaining patient-specific data, meaning host–pathogen interaction could not be determined. Of these, 14 grew one pathogenic organism and 1 grew four distinct pathogens. This is the largest study to date exploring the potential presence of airborne pathogens in room air ventilators. We have demonstrated that 61% of these devices were positive for bacterial or fungal growth and 7% were pathogenic. Pathogenic organisms included Pseudomonas aeruginosa, Staphylococcus aureus and Aspergillus sp. Although the growth of pathogenic organisms was relatively rare, there are important potential adverse clinical outcomes in patients with diseases commonly treated by LTV services. Conclusions: We have shown that the contamination of devices is rare, but, in 7%, there is contamination with potentially pathogenic organisms, which, if proven to be transferred between patients, could be a cause of worse patient outcomes.

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