Positive Airway Pressure for OSA Treatment
The gold standard for the management of OSA is positive airway pressure (PAP). PAP therapy involves the delivery of room air by way of a bedside machine that delivers a column of air to the patient’s airway via some combination of oral or nasal mask and hood. This stream of air prevents airway collapse. The now patent airway allows for delivery of air to the patient which alleviates the symptoms and detrimental adverse effects linked to OSA.
The PAP can be delivered as a continuous air stream (CPAP) or it can be automatically adjustable (APAP). APAP devices sense when the patient exhales and decreases delivery pressure. Upon inspiration it will automatically increase pressure. The sleep physician will initially set the PAP to deliver air at a lower rate such as 6L/minute during the acclimation phase of wearing a PAP device. It may take several weeks of wearing PAP during sleep for patient’s to become accustomed to it. It is not uncommon for the patient to be prescribed a hypnotic to help fall asleep during this period.
Soon thereafter the sleep physician may increase air flow rate to 9L/ minute or higher and titrate to effect. New PAP devices come with a card reader, which can send information to a secure internet cloud for the sleep center staff to monitor compliance, hours of usage and estimate a general AHI. Some companies offer a smart phone or tablet application which can download information via Bluetooth™ to the patient’s device so they can monitor their own progress.
The goal of treatment is to reduce AHI to acceptable levels. As mentioned earlier, reducing the AHI 50% or more (significant improvement) or reducing AHI to under 5 constitute success. In order to show compliance, it is expected that the patient wear the PAP device for at least 4 hours a night; 21 days per a 30-day period (70% of a 30-day period). If the patient is non-compliant, the insurer may take away this service. The above compliance metric is a minimal standard. Providers should aim higher though, such as encouraging about 6 hours of nightly use. One to two months after initiation of PAP, ideally there would be a follow up with the sleep physician to check for improvements in daytime sleepiness, cognitive and other factors.
A typical set up of a bedside, home-use positive airway pressure (PAP) unit.