Sleep apnea literally means absence of breathing during sleep. The reason why you don’t suffocate to death in your sleep is because your body wakes up at least partially in order to be able to breathe, although you probably most likely will not remember this. Because of this frequent partial or complete waking up, the quality of your sleep can suffer substantially. As a result, your daytime performance suffers. You are less energetic and much more apt to fall asleep in inappropriate settings, such as at work, while driving, taking classes, sitting in meetings, and more. In fact, sleep apnea can even wreck your career and possibly your life! In rare cases, it can even cause death.

    There are three basic types of sleep apnea. The most common type is obstructive sleep apnea. Here the airway gets obstructed in one or more locations due to fatty tissues, swelling, and/or physical abnormalities. MOST people that have obstructive sleep apnea are obese. The second type is central sleep apnea. Here the respiratory system makes little or no attempt to breathe during sleep. This defect can either be in the brain, spinal cord, and/or in breathing mechanisms (not reacting to breathing commands from the brain). The last type is mixed sleep apnea. This is simply a combination of obstructive and central sleep apnea put together.

    While there are three basic types of sleep apnea, most of their symptoms are the same. Below are the symptoms of obstructive and central sleep apnea.

• Snoring (sometimes offensively loud—often described like a freight train) *
• Temporary cessations in breathing lasting 10 seconds or more each **
• Hypoxia (lack of oxygen in your bloodstream) **
• Morning headaches
• Daytime sleepiness *
• Lack of energy
• Depression
• Lack of interest in things
• Frequent, but brief awakenings during the night *
• Gasping for breath during sleep *
• Making strange noises during sleep

• Lack of chest movement during sleep **
• Temporary cessations in breathing lasting 10 seconds or more each **
• Hypoxia (lack of oxygen in your bloodstream) **
• Morning headaches
• Daytime sleepiness *
• Lack of energy
• Depression
• Lack of interest in things
• Frequent, but brief awakenings during the night *

    In addition to one or more overnight sleep studies, a person may also undergo a multiple sleep latency test (MSLT). Here, a patient is wired up the same way as for an overnight sleep study, but connected to one or more cables that can be easily connected and disconnected. The person is free to do whatever he or she wants between scheduled nap periods. At regular intervals (usually 2 hours), the person will be connected to the monitoring equipment and be given an opportunity to take a short snooze. If the patient does not fall asleep within an allotted time (usually between 20-35 minutes), he or she is said to be doing satisfactory at that point in the test. The test usually covers the course of a standard workday.

    Many people just simply can’t relax well in a sleep lab, knowing that they are being monitored and have a video camera snooping on them. Here are some tips to help you sleep a significant portion of the night in the lab.

• Do not consume caffeine later than about 2:00 or 3:00 in the afternoon of that day. Most coffee, tea, pop, and chocolate has caffeine in it.
• Do not work hard or exercise no later than about 6:00 or 7:00 that evening.
• Be sure to wash your hair before coming to the hospital.
• Try to adjust your biological "clock" so that you conk out around 10:00 PM (11:30 PM at the latest). Usually, you’ll be put to bed between 10:00 and 11:00 PM. You may need to allow 2-3 weeks to make this adjustment.
• As for behaviors and such, just realize that these technicians have probably seen it all! There is a GOOD chance that what you may do in bed is not near as bad as what some patients do. If you do a lot of tossing or daydreaming, don’t worry. This is normal. Also don’t worry about body positions. Again, these technicians have seen it all!
• Realize that you are in NO danger of electrical shock. The equipment is quote "electrically isolated" and/or "optocoupled." This means that short light beams are used internally to separate the primary amplifiers in which your patient wires lead to and the main amplifiers and other circuitry. This protects you against any "backfiring" that may occur in a monitor that you’re connected to. While it takes at least about 300-1000 microamps (one MILLIONTH of an amp!) to cause even a very slight shock, this equipment, by law, must be designed to allow no more than 20 microamps to enter your body. Normally, hospital standards prefer no more than 10 microamps to go through your body. In fact, the purpose of the equipment is to pick up voltages coming OUT of your body! Yes, your body actually puts out very small voltages (usually less than 2 millivolts or 1/500 of a volt)! These small voltages are picked up by the electrodes attached to your body and then amplified so that they can be processed either for viewing and/or recording. Believe it or not, but the main things that differentiate between EKG’s, EEG’s, and EMG’s are the placement of the electrodes and the amplification factor!
• If you have long hair and particularly if you are due for a haircut, getting a NORMAL haircut is advisable. This makes the prepping process easier. It also makes it easier to get the gel and stuff out of your hair in the morning. Please don’t be insane and try to go bald—This is not necessary!
• If you are worried about your head being one big glob of electrode gel, rest assured that better sleep labs take care of this problem before it even starts! They normally GLUE the wires on your head. This glue dries within seconds. By the time they actually put you in bed, this glue is already complete dried. In the morning, a technician will use a chemical that will quickly break down the glue so that the electrodes can be removed easily. In fact, about 95% of the gook will be removed from your hair before you even leave the lab.
• If the room is too warm or too cold, be sure to speak up early. Better sleep labs have very good climate control that can suit a wide range of patient needs. Don’t feel bad if the technician has to turn on the air condition even in December!