Infection prevention and control
The WHO outlines additional precautions that should be taken to protect healthcare workers during aerosol-generating procedures associated with an increased risk of transmission6. These procedures include tracheal intubation, non-invasive ventilation, tracheotomy, cardiopulmonary resuscitation, manual ventilation before intubation and bronchoscopy.
Nasal High Flow is not specifically named by the WHO as an aerosol-generating procedure associated with an increased risk of transmission.6 However, there has been some uncertainty about the potential creation of aerosols from all forms of noninvasive respiratory support including Nasal High Flow.
According to the WHO: “Because of uncertainty around the potential for aerosolization, HFO, NIV, including bubble CPAP, should be used with airborne precautions until further evaluation of safety can be completed.” 1
Recent publications Hui et al.8, Leung et al.9 and Hui et al.10 compared the application of Nasal High Flow to a range of alternative therapies and interfaces and did not find increased risk of transmission via air dispersion. Collated air dispersion results from two studies conducted by Hui et al.8, 10 are illustrated in the chart below.
Findings of a new study by Kotoda et al.11 suggest that “high-flow nasal therapy does not increase the risk of droplet and contact infection”.
*Dispersion distance data shown on the chart is combined from two studies conducted by the same authors.
Not all of the interfaces depicted were directly compared.