A Quantitative Study of Particle Dispersion due to Respiratory Support Modalities in PC-12 Aircraft: Prehospital Patient Transport

• Published in: Air medical journal Vol. 41; no. 1; pp. 109 - 113
• Main Authors: Peddle, Michael B., Avari, Hamed, Smith, Justin A., Ryzynski, Agnes A., Pinto, Ruxandra, Plenderleith, Simon W., Fowler, Robert A., Tien, Homer, Mubareka, Samira
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.01.2022
• Subjects: Aircraft; Emergency Medical Services; Humans; Noninvasive Ventilation; Oxygen; Oxygen Inhalation Therapy; Respiratory System
• ISSN: 1067-991X; 1532-6497
• DOI: 10.1016/j.amj.2021.10.001

It is unclear whether supplemental oxygen and noninvasive ventilation respiratory support devices increase the dispersion of potentially infectious bioaerosols in a pressurized air medical cabin. This study quantitatively compared particle dispersion from respiratory support modalities in an air medical cabin during flight. Dispersion was measured in a fixed wing air ambulance during flight with a breathing medical mannequin simulator exhaling nebulized saline from the lower respiratory tract with the following respiratory support modalities: a nasal cannula with a surgical mask, high-flow nasal oxygen (HFNO) with a surgical mask, and noninvasive bilevel positive airway pressure (BiPAP) ventilation. Nasal cannula oxygen with a surgical mask was associated with the highest particle concentrations. In the absence of mask seal leaks, BiPAP was associated with 1 order of magnitude lower particle concentration compared with a nasal cannula with a surgical mask. Particle concentrations associated with HFNO with a surgical mask were lower than a nasal cannula with a surgical mask but higher than BiPAP. Particle dispersion associated with the use of BiPAP and HFNO with a surgical mask is lower than nasal cannula oxygen with a surgical mask. These findings may assist air medical organizations with operational decisions where little data exist about respiratory particle dispersion.