Auto titrating continuous positive airway pressure (autoPAP) machines are devices that are set at a variable pressure and adjust the pressure based on the patient’s needs using an internal algorithm. The pressure is monitored and adjusted breath to breath to treat the obstruction. Most devices are sensitive enough to tell the difference between obstructive apnea and central apnea, so that the pressure does not augment for centrals.
AutoPAP devices have been recommended over fixed CPAP (FCPAP) for various reasons. In sixteen randomized controlled trials, autoPAPs were able to reduce the apnea-hypopnea index (AHI) to less than 10 events/hour in 80-95% of patients studied. Many were actually able to reduce the AHI to less than 5 events/hour and did show an improvement in daytime sleepiness.
Currently, insurance companies are the major driving force behind autoPAP usage. Many insurance companies are now requiring home portable studies followed by autoPAP titrations in the home, instead of a formal in-lab titration. This has impacted sleep centers and durable medical equipment (DME) companies significantly over the last two years. AutoPAPs are more expensive than standard CPAP devices, yet the insurance reimbursement is the same between the two devices.
An auto titration study in the home consists of 30 days of auto adjusting pressure and then a download is received either by the insurance company, DME supplier, or sleep clinic. Many devices have a form of remote monitoring so that the third party can view compliance, pressure and efficacy daily during the trial. The autoPAP is then set to FCPAP based on the 90th or 95th percentile pressure. The benefit to this is that you get 30 nights of data instead of just one, as you would with a formal titration study. With this capability, the insurance companies have moved the focus from management of sleep apnea to diagnosis, and this has in turn put sleep apnea on a new level. It is considered a chronic disease and now the management and follow up may be limited.
AutoPAPs have been used in the past for other reasons. Some patients may have an inadequate titration study, and instead of setting a “guessed” fixed pressure, an auto may be recommended. Many times CPAP na‹ve patients want to try the device first and setting an autoPAP for them may eliminate a titration study. Patients who are in the pre-operative phase of any procedure may be limited on time, and after a baseline study, an auto may be prescribed to initiate therapy prior to their procedure. AutoPAPs are also indicated for patients with positional sleep apnea or more sleep stage specific (REM) sleep apnea. The auto adjusting pressure allows for change during the night as their sleep patterns change.