Lab-PSG A polysomnogram monitors a person’s sleep habits overnight in a sleep lab. The sleep technologist will position tiny painless sensors to different points on the patient’s body to record brain waves, respiratory flow, blood oxygen level, muscle activity, heart rhythm, body position and other body functions during sleep.
During a sleep study, the technologist is in constant video and audio contact with the patient, providing a safe, supportive environment with minimal anxiety.
Treatments for sleep and breathing disorders such as sleep apnea, including the administration of positive airway pressure (PAP) and nocturnal oxygen, are frequently initiated during a PSG.
PAP Titration Study
Lab-CPAP A positive airway pressure (PAP) titration study is performed on someone who has already been diagnosed with sleep apnea or a sleep-related breathing disorder by a PSG.
In addition to all the sensors used in a PSG, the sleep technologist will help the patient to find a comfortable mask that best fits his or her face. When connected to a small flow generator, the mask allows air to gently blow into the back of the patient’s throat to maintain an open upper airway so that the patient can breathe normally. The air flow pressure is gradually increased during the night, in order to find the right level of air pressure that will prevent the collapse of the patient’s upper airway. This will eliminate loud snoring and maintain an adequate blood oxygen level.
Nap Studies – Multiple Sleep Latency Test (MSLT) & Maintenance of Wakefulness Test (MWT)
Lab-MSLT-MWT Both nap studies are done during the daytime. MSLT is used to see how quickly a person falls asleep in quiet situations during the day. This test is the standard way to objectively measure an individual’s level of daytime sleepiness and is used to diagnose hypersomnias such as narcolepsy. The study is always preceded by an overnight PSG in the lab. It consists of a series of daytime naps in which the patient’s sleep is monitored, with similar sensors as those used in a PSG.
In contrast, the MWT is used to measure how alert a person is during the day and it shows whether or not the individual is able to stay awake for a defined period of time. This is an indicator of how well a person is able to function and remain alert in quiet times of inactivity. Unlike the MSLT, MWT is not preceded by an overnight PSG. It consists of a series of sleep trials during which the sleep technologist will monitor the patient’s ability to resist the urge to fall asleep.
Home Sleep Study
A home sleep test involves the use of a portable monitoring device that is worn while sleeping. The patient would come to our clinic and be instructed on how to put on the device by our sleep technologist. After the night is over, the portable monitoring device is returned to our clinic and its recorded data will be promptly interpreted.
Home sleep study has the benefits of sleeping in one’s own bed and not have the nightly routine interrupted. However, a home sleep study is only applicable to a selected group of patients and only used to diagnose obstructive sleep apnea. Furthermore, it is only conducted as part of a comprehensive sleep evaluation performed by our medical director.