Sounds useful 4 winter!

NEW YORK (Reuters Health) - A heat exchange mask, designed to improve comfort in cold temperatures, also seems to protect against asthma triggered by breathing cold, dry air, according to a report in the medical journal Chest.

Asthma occurs when the airways tighten, limiting breathing.

Cold, dry air is one of the most common triggers of an asthma attack.

The Qxtec Personal Respiratory Heat Exchanger, marketed by Louisville,

Kentucky-based AllergyZone, works by conserving the heat and humidity of exhaled air and applying it to inhaled air.

As such, the device does not require batteries.

""The mask was originally designed to make breathing more comfortable"" for people working or playing in cold environments,

lead author Dr. David A. Beuther, from the University of Colorado at Denver,

told Reuters Health...

""We decided to study the mask's use for cold exercise-induced asthma after the manufacturer came to us describing asthmatic patients who reported improvements with the device.""

In the first part of the study, 13 patients with cold exercise-induced asthma completed treadmill tests while breathing cold air through a real or fake heat mask.

Although the cold air caused lung function to worsen in both groups, the effect was much less pronounced in the group given real heat masks.

In the second part of the study, five patients breathed cold air and then performed three treadmill tests with the heat mask, with the airway-opening drug albuterol, or without either intervention.

The mask and albuterol appeared to be comparable in preserving lung function.

Beuther said that he believes the manufacturer is planning to approach the US Food and Drug Administration to seek an asthma indication for the device.

He emphasized that he envisions the mask as an addition to drug therapy for patients who have cold exercise-induced asthma, ""not a replacement.