Ventilation systems and methods employing aerosol generators

1. A method of delivering a surfactant to a patient's respiratory system which comprises the steps of:

providing a CPAP system having a pressure-generating circuit with a first gas flow of sufficiently high volume to maintain continuous positive airway pressure in the system, a respiratory circuit connecting the pressure-generating circuit to a patient interface device, wherein the respiratory circuit contains a second gas flow of lower volume than said first gas flow, and a vibrating aperture nebulizer coupled to the respiratory circuit at a distance from the patient interface device sufficient to provide an acceptable efficiency of delivering a liquid surfactant to the patient's respiratory system;

introducing the liquid surfactant into the nebulizer;

aerosolizing the surfactant in the nebulizer; and

entraining the aerosolized surfactant into the second gas flow of the respiratory circuit to avoid dilution of the aerosolized surfactant delivered to the patient.

2. The method of claim 1 wherein the surfactant is a phospholipid.

3. The method of claim 1 wherein 6-18% of the aerosolized surfactant introduced into the system is delivered to the patient.

4. The method of claim 1 wherein the nebulizer comprises a reservoir having a capacity substantially equal one unit dose of surfactant and substantially all of the contents of the reservoir is delivered to the patient.

5. The method of claim 1 wherein the dose is equal to 10 mg or less of surfactant.

6. The method of claim 1 wherein the patient interface device is selected from the group consisting of nasal prongs, an oral/nasal mask, a nasal mask, nasopharyngeal prongs, a nasopharyngeal tube, a tracheotomy tube, an endotracheal tube and a mouthpiece.

7. The method of claim 6 wherein the patient interface device is an endotracheal tube.