AIRWAY BARRIER ENCLOSURES
Several enclosures for placement around the head and upper torso have been described during this pandemic (Anesth Analg 2020;131:e135-36; J Cardiothorac Vasc Anesth 2021;35:966-67). They are usually made of frames covered by transparent sheets. The enclosures have access ports for the operator's arms, supplemental oxygen, and airway equipment. The enclosures do not form an airtight seal around the patient's head and torso. They provide partial source control by suctioning aerosol and infectious droplets. If suction devices currently available in hospitals are utilized, the enclosure may only slightly reduce interior pressures relative to the ambient pressure. Hopefully most infectious material remains inside the enclosure, but during doffing and disposal contaminated material may escape.
Although an enclosure may reduce health care personnel (HCP) exposure, full personal protective equipment (PPE) is still required. No studies demonstrate safety, efficacy, or usability. What is unambiguous is that airway enclosures adversely affect visibility and maneuverability. As a result, airway enclosures likely complicate airway management.
The relevance of articles demonstrating utility in mannequins or healthy volunteers briefly ensconsed in an enclosure is limited (Anesth Analg 2020;131: e135-36; J Cardiothorac Vasc Anesth 2021;35:966-67), as patients with COVID-19 requiring emergency intubation will likely be claustrophobic and agitated.
Why it matters
Respiratory transmission of pathogens is a major concern. Early in the pandemic, airway barrier enclosures were proposed for infection control. However, a detailed analysis has identified problems with them. Appropriate PPE is essential. Covering the patient's face with a mask and a clear plastic drape provides partial source control.