The effect of an air purifier on aerosol generation measurements during clinical motility testing.
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ABSTRACT: Background
Aerosol spread is key to interpret the risk of viral contamination during clinical procedures such as esophageal high-resolution manometry (HRM). Installing an air purifier seems a legitimate strategy, but this has recently been questioned.Methods
Patients undergoing an HRM procedure at the Leuven University Hospital were included in this clinical study. All subjects had to wear a surgical mask which was only lowered beneath the nose during the placement and removal of the nasogastric catheter. The number of aerosol particles was measured by a Lasair® II Particle Counter to obtain data about different particles sizes: 0.3; 0.5; 1.0; 3.0; 5.0; and 10.0 µm. Measurements were done immediately before the placement and the removal of the HRM catheter, and one and 5 min after. A portable air purifier with high-efficiency particle air filters was installed in the hospital room.Key results
Thirteen patients underwent a manometry examination. The amount of 0.3 µm-sized particles was unaffected during the whole procedure. The larger particle sizes (1.0; 3.0; 5.0; and 10.0 µm) decreased when the catheter was positioned, but not 0.5 µm. During the HRM measurements itself, these numbers decreased further. Yet, 1 min after catheter removal a significant elevation of particles was seen, which did not recover within 5 min.Conclusions & interferences
Based on this study, there is no evidence that filtration systems reduce aerosol particles properly during a clinical investigation.
SUBMITTER: Verbeure W
PROVIDER: S-EPMC8420584 | biostudies-literature |
REPOSITORIES: biostudies-literature
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2023-09-01 | GSE221401 | GEO