What is REM Rebound? A Sleep Technologist's Guide
What is REM Rebound? What should sleep technologists know about it?
REM sleep rebound is identified as the increase of Stage R sleep above normal (or baseline) levels after a period of sleep restriction or deprivation. In other words, it's a phenomenon in which there is an increase in REM sleep after a night of little REM sleep. Generally a 20% increase in REM sleep duration has been proposed as a threshold to identify REM rebound in patients with obstructive sleep apnea (OSA) who start PAP treatment.
Why sleep technologists should pay attention to this condition
According to a study published by Case Reports in Medicine titled "Extreme REM Rebound during Continuous Positive Airway Pressure Titration for Obstructive Sleep Apnea in a Depressed Patient," REM rebound could be of clinical relevance in OSA patients who are at risk of hypoventilation during REM sleep when CPAP treatment is initiated. " This study's research suggested that starting CPAP treatment and withdrawal of REM suppressing substances may have additional effects on sleep architecture.
In this particular study it seemed as if no dangerous consequences occurred from the patient's excessive REM sleep period. In fact, some sleep technologists would describe REM rebound as a curiousity rather than a concern. However, as noted above the study suggested that a very long duration of REM sleep could be of clinical relevance in OSA patients.
From a patient's perspective, experiencing REM rebound often includes having vivid dreams, nightmares, a groggy diconnected feeling upon waking in the morning, and occasionally morning headaches.
Learning about sleep stages and PAP titration
To learn how sleep technologists should titrate PAP in patients who exhibit symptoms of REM rebound, it's important to recognize the various sleep stages and understand the effects of PAP titration on sleep. In this AAST Case of the Month, Dr. Rosenberg discusses stage N3 and stage R rebound sleep in a patient with OSA titrated using PAP therapy.
The online module discusses the initial inadequate pressures and the changes that occurred when an acceptable pressure was quickly reached. The patient's rebound of stage N3 and stage R sleep are compared with normative data for age. Typical changes in sleep stages that occur during the first night of titration are also discussed.