Recovery from Sleep Deprivation Occurs during Propofol

Background: Some neurophysiologic similarities between sleep and anesthesia suggest that an anesthetized state may reverse effects of sleep deprivation. The effect of anesthesia on sleep homeostasis, however, is unknown. To test the hypothesis that recovery from sleep deprivation occurs during anesthesia, the authors followed 24 h of sleep deprivation in the rat with a 6-h period of either ad libitum sleep or propofol anesthesia, and compared subsequent sleep characteristics. Methods: With animal care committee approval, electroencephalographic/electromyographic electrodes and intrajugular cannulae were implanted in 32 rats. After a 7-day recovery and 24-h baseline electroencephalographic/electromyographic recording period, rats were sleep deprived for 24 h by the diskover-water method. Rats then underwen t6ho feither propofol anesthesia (n 16) or ad libitum sleep with intralipid administration (n 16), followed by electroencephalographic/ electromyographic monitoring for 72 h. Results: In control rats, increases above baseline in non–rapid eye movement sleep, rapid eye movement sleep, and non–rapid eye movement delta power persisted for 12 h after 24 h of sleep deprivation. Recovery from sleep deprivation in anesthetized rats was similar in timing to that of controls. No delayed rebound effects were observed in either group for 72 h after deprivation. Conclusion: These data show that a recovery process similar to that occurring during naturally occurring sleep also takes place during anesthesia and suggest that sleep and anesthesia share common regulatory mechanisms. Such interactions between sleep and anesthesia may allow anesthesiologists to better understand a potentially important source of variability in anesthetic action and raise the possibility that anesthetics may facilitate sleep in environments where sleep deprivation is common. SLEEP deprivation is common in patients in the intensive care unit 1 and can result in worsened agitation and respiratory, immune, and endocrine system dysfunction. 2–4 Although naturally occurring sleep readily reverses consequences of sleep deprivation, 5 such sleep can be difficult to obtain in an intensive care environment. In sleep-deprived critically ill patients, behavioral similarities between levels of sedation approaching general anesthesia and naturally occurring sleep have raised the possibility that the anesthetized state may substitute for sleep and may thus allow recovery from sleep deprivation. 6,7