Dataset Information

Exhalation Spreading During Nasal High-Flow Therapy at Different Flow Rates.

ABSTRACT:

Objectives

Severe acute respiratory syndrome coronavirus 2 is transmitted through aerosols and droplets. Nasal high-flow therapy could possibly increase the spreading of exhalates from patients. The aim of this study is to investigate whether nasal high-flow therapy affects the range of the expiratory plume compared with spontaneous breathing.

Design

Interventional experiment on single breaths of a healthy volunteer.

Setting

Research laboratory at the Bauhaus-University Weimar.

Subjects

A male subject.

Interventions

Videos and images from a schlieren optical system were analyzed during spontaneous breathing and different nasal high-flow rates.

Measurements and main results

The maximal exhalation spread was 0.99, 2.18, 2.92, and 4.1 m during spontaneous breathing, nasal high-flow of 20 L/min, nasal high-flow of 40 L/min, and nasal high-flow of 60 L/min, respectively. Spreading of the expiratory plume in the sagittal plane can completely be blocked with a surgical mask.

Conclusions

Nasal high-flow therapy increases the range of the expiratory air up to more than 4 meters. The risk to pick up infectious particles could be increased within this range. Attachment of a surgical mask over the nasal high-flow cannula blocks the expiratory airstream.

SUBMITTER: Dellweg D

PROVIDER: S-EPMC8204857 | biostudies-literature |

REPOSITORIES: biostudies-literature

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