Anesthesiology
-
The psychologic effect of the preoperative visit by an anesthetist has been compared with the effect of pentobarbital for preanesthetic medication. Patients receiving pentobarbital 1 hour before an operation became drowsy but it could not be shown that they became calm. ⋯ The importance of the preoperative visit probably explains, in part, the difficulties previous investigators have had in showing sedative effects from the barbiturates and narcotics before operation. The tremendous emotional significance to a patient of illness or an operation may explain why physicians are able to exert such influence upon their patients.
-
The psychedelic experience has been reported since antiquity, but there is relatively little known about the underlying neural mechanisms. A recent neuroimaging study on psilocybin revealed a pattern of decreased cerebral blood flow and functional disconnections that is surprisingly similar to that caused by various anesthetics. In this article, the authors review historical examples of psychedelic experiences induced by general anesthetics and then contrast the mechanisms by which these two drug classes generate altered states of consciousness.
-
Microglial activation is implicated in delayed tissue damage after traumatic brain injury (TBI). Activation of microglia causes up-regulation of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, with the release of reactive oxygen species and cytotoxicity. Propofol appears to have antiinflammatory actions. The authors evaluated the neuroprotective effects of propofol after TBI and examined in vivo and in vitro whether such actions reflected modulation of NADPH oxidase. ⋯ The neuroprotective effects of propofol after TBI appear to be mediated, in part, through the inhibition of NADPH oxidase.