In contrast, Manser says, a person's passive vocabulary consists of the words whose meanings they knowâso that they do not have to look the words up in a dictionaryâbut which they would not necessarily use in ordinary conversation or writing (The Penguin Writer's Manual, 2004).
Sleep Apnea, Night Terrors, and Nightmares. Sleep apnea may also be to blame for your nightmares. During sleep apnea, your brain senses the low oxygen and realizes that you are under a very real threatâyou are being choked or smothered by your own bodyâand if nothing is done you will die.
Another great question. Oxygen levels are lower for everyone during sleep. This relates to a more shallow breathing pattern that we all assume during sleep. Some alveoli drop out of use so 02 levels fall. If you are starting out with an awake 02SAT above 94% it is unlikely that the sleep level will be below 88%. It is best, however, to do a sleep oximetry study and see the actual 02 levels at night.