Heliox in acute severe asthma in the A&E setting: a review

Abstract

Heliox (HeO₂) is a mixture of helium and oxygen, often mixed in 80:20 or 70:30 ratios for use in medicine and clinical investigations. Heliox has been available for use in the UK since 2002 and is supplied as Heliox 21 (21% oxygen and 79% helium) by BOC Gases for medical use in asthma, croup, chronic obstructive pulmonary disease and other medical procedures. Heliox use in asthma exacerbations remains largely experimental owing to the limited number of randomized controlled trials. This review aims to critically analyse the efficiency of Heliox use in acute asthma exacerbations in the Accident and Emergency (A&E) setting, evaluate its effectiveness as a medium for nebulization, and assess potential benefits to clinical practice. Prehospital application will also be discussed in moderate-severe asthma exacerbations. It is envisaged that the factors relating to Heliox use in asthma are focused to provide an additional therapy to the current choice of therapies for prehospital clinicians.