Polysomnography and Continuous Positive Airway Pressure (CPAP) Titration

Polysomnography (PSG) is a detailed diagnostic test used to study and evaluate sleep disorders. Often referred to as a “sleep study,” polysomnography records various physiological parameters during sleep, providing comprehensive insights into a person’s sleep architecture and identifying any abnormalities that may be disrupting restorative rest.

What Is Polysomnography?

The term “polysomnography” derives from Greek words meaning “many sleep recordings.” This test simultaneously measures multiple body functions during sleep, including brain activity, eye movements, muscle activity, heart rhythm, breathing medico del sonno patterns, oxygen levels, and limb movements. The resulting data allows clinicians to analyze sleep stages, identify disturbances, and diagnose conditions that impair sleep quality and overall health.

Why Is Polysomnography Important?

Sleep plays a vital role in physical and mental health. Poor or disrupted sleep can contribute to a wide range of problems such as excessive daytime fatigue, impaired cognitive function, mood disorders, cardiovascular disease, and metabolic conditions like diabetes. Polysomnography is crucial for diagnosing many sleep disorders, which often go unrecognized or misdiagnosed due to the complex nature of sleep and its disorders.

Common Conditions Diagnosed with Polysomnography

• Obstructive Sleep Apnea (OSA): One of the most common sleep disorders, OSA occurs when the airway repeatedly becomes blocked during sleep, leading to breathing pauses and fragmented sleep. PSG helps identify these apneas and hypopneas, as well as associated oxygen desaturation.

• Narcolepsy: Characterized by excessive daytime sleepiness and sudden sleep attacks, narcolepsy can be diagnosed by assessing abnormal REM sleep patterns with polysomnography combined with additional tests.

• Periodic Limb Movement Disorder (PLMD): This condition involves repetitive limb movements during sleep that disrupt rest. PSG records limb electromyography (EMG) to detect such movements.

• Parasomnias: Disorders like sleepwalking, night terrors, and REM sleep behavior disorder can also be evaluated through PSG.

How Is Polysomnography Performed?

The test is typically conducted overnight in a specialized sleep laboratory or, increasingly, at home with portable devices. Before sleep, sensors are placed on the scalp, face, chest, limbs, and finger. These sensors include:

• Electroencephalogram (EEG) electrodes to monitor brain waves.

• Electrooculogram (EOG) to track eye movements.

• Electromyogram (EMG) to measure muscle activity.

• Electrocardiogram (ECG) to record heart rate and rhythm.

• Respiratory belts and airflow sensors to measure breathing effort and airflow.

• Pulse oximeter to monitor blood oxygen saturation.

Throughout the night, data is collected and later analyzed by sleep specialists to determine sleep stages, detect abnormalities, and diagnose disorders.

Benefits and Limitations

Polysomnography is the gold standard for diagnosing sleep disorders due to its comprehensive data collection. It guides effective treatment planning, which can significantly improve quality of life. However, it can be costly and may cause discomfort due to the sensors, potentially affecting natural sleep. Home-based tests are becoming more common but may not be as detailed.

Polysomnography remains an essential tool in sleep medicine, providing critical insights into the complex processes of sleep and its disturbances. For anyone experiencing unexplained daytime fatigue, snoring, or other signs of poor sleep, consulting a healthcare provider about the possibility of a sleep study could be life-changing. By identifying underlying sleep disorders, polysomnography helps pave the way toward better health and well-being.