METHODS AND APPARATUS FOR SUPPLYING CLEAN BREATHABLE GAS

The invention features methods and apparatus for the treatment of asthma patients. A controlled supply of breathable air delivered to a patient interface or mask (4) is controlled for patient comfort to maintain a steady pressure level in a range 2 to 4 cm H2O to accommodate patient respiration. The breathable air is cleaned by a high efficiency particulate arresting filter (10) to remove allergens from the air supply. The apparatus may be programmed to automatically detect asthma-related symptoms such as an asthma attack by analyzing the respiratory flow of the patient. In response to the detection of such an attack, the apparatus may provide an audible warning or if configured with a treatment delivery module (14A, 14B), the device may administer a therapeutically effective dose of a drug or substance, for example, a broncho-dilator, to alleviate the patient's breathing difficulty. Preferred mask designs allow for proper CO2 washout to accommodate the low pressures supplied to the mask and prevent asphyxia.