Helium was discovered in 1868 by the French astronomer Pierre-Jules-César
Janssen and was first used as a therapeutic treatment for airway obstruction by
Barach almost 70 years later, in 1934. Heliox is characterized by its low
density, which makes it more fluid under conditions of turbulence, thus
minimizing airway pressure and facilitating the occurrence of laminar flow. The
present article describes two clinical cases of patients with status asthmaticus
subjected to mechanical ventilation and refractory to treatment in whom heliox
was used, which allowed optimization of the efficacy of conventional
pharmacological treatments. Although heliox is still used sporadically and its
true efficacy has not been well demonstrated, the unique physical properties of
helium and the theoretical improvement of the airflow in obstructed airways have
produced scientific interest and stimulated research. Heliox can be used
simultaneously with conventional therapies in cases of serious and refractory
exacerbations of severe obstructive disease.