What Researchers Did
Researchers tested how albuterol inhalers worked under different hyperbaric pressures, from normal air pressure up to 3 ATA (66 feet of seawater).
What They Found
At 3 ATA, CFC and long canister HFA inhalers delivered 13% and 12% less medication per puff, respectively, compared to normal pressure, while short canister HFA inhalers were unaffected. Particle sizes from CFC and short canister HFA inhalers decreased from 50 nm to 32 nm at 3 ATA, and the number of particles delivered dropped significantly for all types, with CFC and long canister HFA delivering only 4-7% of particles and short canister HFA delivering 26%.
What This Means for Canadian Patients
Patients with asthma or similar conditions who might need to use an albuterol inhaler during hyperbaric exposure, such as HBOT or diving, should be aware that the inhaler's effectiveness can change depending on the canister type and pressure. This suggests that some inhalers may not deliver the expected dose or particle size in a hyperbaric environment. Patients should discuss their specific inhaler type with their healthcare provider if they anticipate hyperbaric exposure.
Canadian Relevance
No direct Canadian connection identified.
Study Limitations
This study was conducted in a hyperbaric chamber and did not involve human patients, focusing only on albuterol MDIs.