Asthmatics have it hard enough when they're awake, having to periodically use their inhalers, or remove themselves from situations that could trigger an attack. For some of them, however, their symptoms get even worse when they go to bed, preventing them from getting a good night's sleep. Airsonett, a Swedish medical tech company, is attempting make life easier for those people. It has created a device called the Protexo, which it claims should be of great assistance to night-time asthma sufferers.

According to Airsonett, the heat rising from the exposed skin of a sleeping person creates a chimney effect, drawing cooler air from the immediate vicinity towards the head, and then up. As that air travels through and across the bed sheets (which are a significant source of allergens), it picks up particles from those sheets and brings them to the person's nose, where they are inhaled.

The Protexo works by gently blowing a stream of filtered air down onto the person, that air being slightly cooler than the air in the room. This cancels out the chimney effect, and in fact serves to move the particle-laden air away from the person's face. The device is apparently able to modulate the velocity of its air flow, in order to break the convection effect, while still creating as little draft as possible.

Known as Temperature controlled laminar airflow treatment, or TLA, the technology has reportedly been shown to result in a 3,000-fold reduction of particles measuring half a micron and larger, as measured in the breathing zone. It is also said to improve on the performance of a best-in-class air purifier by a further 99 percent.

In a recent year-long study, a group of 281 non-smoking asthma sufferers from six European countries regularly used either a Protexo, or a dummy device. At the end of the trial, the Protexo group scored 14 to 15 percent higher when evaluating their quality of life, but also showed significant decreases in nitric oxide and immunoglobulin E levels, both of which are indicators of inflammation.

There's no word on pricing or availability, but interested parties can find more information on the Airsonett website.