Back to Search Start Over

Low minute volume rescue oxygenation after cannula cricothyroidotomy in the can't intubate can't oxygenate scenario

Authors :
David Lacquiere
James Dinsmore
A. M. B. Heard
Source :
Br J Anaesth
Publication Year :
2021
Publisher :
Elsevier BV, 2021.

Abstract

BACKGROUND: During induction of general anaesthesia, patients frequently experience apnoea, which can lead to dangerous hypoxaemia. An obstructed upper airway can impede attempts to provide ventilation. Although unrelieved apnoea is rare, it continues to cause deaths. Clinical investigation of management strategies for such scenarios is effectively impossible because of ethical and practical considerations. METHODS: A population-representative cohort of 100 virtual (in silico) subjects was configured using a high-fidelity computational model of the pulmonary and cardiovascular systems. Each subject breathed 100% oxygen for 3 min and then became apnoeic, with an obstructed upper airway, during induction of general anaesthesia. Apnoea continued throughout the protocol. When arterial oxygen saturation (Sao(2)) reached 20%, 40%, or 60%, airway obstruction was relieved. We examined the effect of varying supraglottic oxygen fraction (Fo(2)) on the degree of passive re-oxygenation occurring without tidal ventilation. RESULTS: Relief of airway obstruction during apnoea produced a single, passive inhalation (caused by intrathoracic hypobaric pressure) in all cases. The degree of re-oxygenation after airway opening was markedly influenced by the supraglottic Fo(2), with a supraglottic Fo(2) of 100% providing significant and sustained re-oxygenation (post-rescue Pao(2) 42.3 [4.4] kPa, when the airway rescue occurred after desaturation to Sao(2) 60%). CONCLUSIONS: Supraglottic oxygen supplementation before relieving upper airway obstruction improves the effectiveness of simulated airway rescue. Management strategies should be implemented to assure a substantially increased pharyngeal Fo(2) during difficult airway management.

Details

ISSN :
00070912
Volume :
127
Database :
OpenAIRE
Journal :
British Journal of Anaesthesia
Accession number :
edsair.doi.dedup.....d9c16c11c91e4ecfe81110264eceaaa6
Full Text :
https://doi.org/10.1016/j.bja.2021.05.010