Which medical gas is often used to treat airway obstruction and as a method of aerosol delivery for medications?

Helium is commonly used in medical settings for its unique physical properties, especially in the treatment of airway obstruction. When helium is combined with oxygen, it creates a therapy known as heliox. Helium's low density leads to decreased airway resistance, making it easier for patients with obstructed airways to breathe. This is particularly beneficial in conditions such as asthma or chronic obstructive pulmonary disease (COPD), where airflow is compromised.

Moreover, helium as an aerosol carrier can facilitate the delivery of medications directly into the lungs. Its ability to penetrate the airways more efficiently than conventional air enhances the distribution of aerosolized drugs, contributing to effective treatment.

In contrast, oxygen is primarily utilized for enhancing oxygenation and does not serve the same functions for obstructed airways or medication delivery. Nitric oxide is primarily used for pulmonary hypertension and does not aid in aerosol delivery for common obstructive conditions. Carbon dioxide has its own specific applications, primarily in diagnostics and therapeutic interventions, but it is not used for treating airway obstruction or aerosol medication delivery.