Details of CPAP and Mechanical Ventilation Application
The patients who demonstrated obstructive sleep apnea, mixed apnea, or hypoventilation syndrome were first tried on nasal CPAP with an appropriately fitting nasal mask. The CPAP was started at 5 cmll20 at night while polysomnography was being done. The CPAP was titrated in increments of 2.5 cmll20 pressure in order to determine a proper level and the efficacy of the treatment. Those who were treated were followed up in four to six months with night polysomnography to ensure continuing effectiveness of treatment and a clinical evaluation of patients general condition.
Those who were not treated effectively with CPAP then received nasal mask intermittent positive pressure ventilation with a portable home volume ventilator. This ventilator was set up in a time cycled pressure limited mode using the Lifecare pressure limiting valve. The patients were fitted with two types of nasal masks which were used on a rotational basis to avoid consistent pressure points. These systems were tested while polysomnography was being done to ensure efficacy throughout NREM and REM sleep. These individuals were ventilated with room air. ventolin inhalers
An artificial nose, placed between the exhalation valve and the patient, was used in line if necessary for humidification. The air was driven through the pressure limit valve attached to corrugated tubing, one way valve, exhalation valve, artificial nose, inspiratory assist line, and patient nasal mask. The one way valve essentially provided for a noncontaminated circuit so that circuit cleaning at home would be simplified. These patients were then followed at home on a daily basis for two weeks and then a weekly basis for four weeks, then a monthly basis until approximately six months at which time follow-up polysomnography was done and patients were re-evaluated for improvement or changes in their general condition.