CPAP (Continuous Positive Airway Pressure)

A mask through the patients nose delivers continuous Positive Airway Pressure (CPAP). A constant stream of room air, often heated and humidified, is sent from a small blower at the patient’s bedside. The pressure is not enough to interfere with normal breathing, but it is thought that the stimulation of the airflow on the upper airway is enough to keep the airway open. Each patient requires a different amount of airflow. The effective airflow for each patient is traditionally obtained in the sleep lab as part of a titration study. In some labs, this study may be done on the same night as the sleep study – a so-called Split Night Study. In others, a titration study is done on the following night.

The technical applies the CPAP and sets the pressure value; the value is increased or decreased, until the lowest effective level is found. The patient is then provided with a CPAP machine fixed at that setting. This model of treatment suffers from the same problems as in-lab diagnostic testing. It requires trained technicians in a sleep clinic. The Patient encounters the same backlog, the same bottleneck, and inconvenience. If the time between diagnosis and treatment is prolonged because of accessibility, the risk of legal liability may become an issue.

CPAP is a treatment, nothing more. It is not a cure. It is worn, every night. The effect on the Apnea/Hypopnea index and overall sleep is immediate. Patients often report waking up the next morning, feeling like a new person. The effect on nocturnal blood pressure is immediate as well. A drop in daytime blood pressure may be seen in a few days or weeks. All of these effects are reversed if the CPAP is not worn.

The American Thoracic Society has an official statement on this matter, “CPAP is effective in eliminating Obstructive Sleep Apnea, Oxyhemoglobin desaturation, and respiratory related arousal from sleep. CPAP is also associated with improved morbidity as manifested in primarily a reduction is daytime sleepiness, and improved cardiopulmonary function. Although the long term effects of nasal CPAP have not been fully determined, available data suggests a possible reduction in mortality.”