The Relationship Between Different Doses of Propofol and the Occurrence of Dreams in Short Surgery Under General Anesthesia

Dreams are a remarkable experiment in psychology and neuroscience, conducted every night in every sleeping person. 74% of awakenings from REM sleep resulted in recall of a dream, as compared with only 9% of awakenings from NREM sleep. The association between dreaming and REM sleep was subsequently replicated by many other investigators; typically, around 80% of REM awakenings yield dreams. It became clear over time that there is a good deal of mental activity that occurs during NREM sleep. Typically, it is more thought like, fragmentary, and related to daily concerns than the vivid, hallucinatory, predominantly visual narratives that are most commonly reported from REM sleep. But even this distinction appears not to be absolute. There is now wide acceptance of the view that some dreaming that is indistinguishable from REM sleep dreaming occurs in NREM sleep, most frequently in the sleep-onset period. General anesthesia causes a drug-induced state of unconsciousness and is a non-physiological process that is similar to natural sleep. Patients receiving propofol for maintenance of general anesthesia often report higher incidences of dreaming than patients maintained with volatile anesthetics. One explanation is that propofol and volatile anesthetic have different pharmacological effects in the central nervous system. An alternative explanation is that propofol is associated with more rapid emergence from anesthesia than the older volatile anesthetics, allowing patients to report their dreams before they are forgotten. In order to further verify the hypothesis, the investigators choose gynecological general anesthesia to observe whether the generation of dreams is related to the dose of general anesthesia maintenance .