Positive Airway Pressure (PAP) therapy is a common, non-invasive medical treatment designed to support a patient’s breathing, typically during sleep. This therapy uses a bedside device to generate a continuous stream of pressurized air, delivered through a hose and a mask interface. PAP therapy assists in maintaining an open airway, ensuring breathing remains regular and uninterrupted. This process provides mechanical support without requiring more invasive ventilatory methods.
The Primary Medical Indication for PAP Therapy
PAP therapy is primarily prescribed for Sleep-Disordered Breathing, most often Obstructive Sleep Apnea (OSA). OSA occurs when the muscles and soft tissues in the back of the throat relax during sleep, causing the upper airway to partially or completely collapse. This physical obstruction leads to a cessation or significant reduction in airflow, known as an apnea or hypopnea event. These episodes can occur dozens of times per hour, fragmenting sleep and preventing restorative rest.
These breathing interruptions cause repeated drops in blood oxygen saturation levels. The brain senses this desaturation and triggers a partial awakening, or arousal, to restart breathing. Over time, the chronic stress from interrupted breathing and poor oxygenation contributes to serious systemic conditions. Untreated OSA is linked to an increased risk for high blood pressure, cardiovascular disease, stroke, and Type 2 diabetes.
Mechanism of Action and Device Types
PAP therapy works by delivering a constant column of pressurized air to the upper airway, which acts as a “pneumatic splint.” This positive pressure physically holds the collapsible soft tissues open, preventing the obstruction that defines OSA. Maintaining a clear and patent airway allows for normal, uninterrupted breathing and oxygen flow throughout the night. The specific pressure required to eliminate breathing events is determined during a specialized sleep study.
Continuous Positive Airway Pressure (CPAP)
The most common form is CPAP, which delivers a single, fixed pressure setting throughout the night. This pressure remains constant regardless of whether the user is inhaling or exhaling.
Automatic Positive Airway Pressure (APAP)
APAP utilizes an algorithm to monitor the user’s breathing patterns moment-to-moment. The APAP machine automatically adjusts the pressure within a prescribed range, increasing it only when it detects a partial or complete obstruction. This dynamic adjustment often makes APAP a more comfortable option for many users.
Bilevel Positive Airway Pressure (BiPAP)
BiPAP provides two distinct pressure settings. It delivers a higher pressure when the user inhales (Inspiratory Positive Airway Pressure, or IPAP) and a lower pressure when the user exhales (Expiratory Positive Airway Pressure, or EPAP). The pressure difference makes it easier to breathe out against the forced airflow, benefiting patients who require higher overall treatment pressures. BiPAP is also used for individuals with central sleep apnea or certain other respiratory conditions.
Understanding the PAP System Components
The PAP system consists of three main physical components that work together to deliver the pressurized air:
- The main PAP unit is a compact bedside machine housing the motor and pressure-generating mechanism. This unit draws in ambient room air, filters it, and pressurizes it according to prescribed settings. The machine often contains data storage to record therapy usage and effectiveness for healthcare providers.
- The interface, or mask, connects the machine to the user’s airway. Primary mask types include nasal pillows (sealing at the nostrils), nasal masks (covering the nose), and full face masks (covering the nose and mouth). Selecting the correct mask and ensuring a proper, leak-free seal is important for comfort and therapy success, as leaks reduce effectiveness.
- The tubing and optional heated humidifier connect to the main unit. Flexible tubing carries the pressurized air to the mask interface. Many PAP units feature a built-in heated humidifier, which adds moisture to the airflow, preventing side effects like nasal dryness and irritation. Distilled water is recommended to prevent mineral buildup.
Initiating and Managing Treatment
Initiating Treatment
Starting PAP therapy begins with a diagnostic sleep study (polysomnography) to confirm the presence and severity of sleep-disordered breathing. If OSA is diagnosed, a sleep specialist issues a prescription specifying the device type and pressure settings. Often, a second sleep study, known as a titration study, is conducted to manually determine the precise pressure required to eliminate respiratory events. Some facilities use a “split-night” study, where diagnosis and titration occur during the same night.
Ongoing Management and Maintenance
Effective management requires consistent daily use and attention to equipment maintenance to ensure long-term adherence. New users often need to troubleshoot common initial discomforts, such as dry mouth or nasal congestion, which can often be solved by adjusting the heated humidifier settings. Mask leaks are a frequent challenge, typically managed by adjusting the headgear straps or switching to a different mask style. If the patient has difficulty exhaling against the pressure, the physician may enable pressure-relief features or switch the patient to a BiPAP device.
Proper cleaning is important to maintain comfort and device function. The mask cushion and the humidifier water chamber should be cleaned daily with mild soap and water to remove facial oils and mineral deposits. Weekly cleaning of the tubing and headgear is also recommended, followed by complete air drying to prevent the growth of mold or bacteria. Regular follow-up with a sleep physician allows for monitoring of PAP usage data and necessary pressure adjustments to maximize therapeutic benefit.