General anaesthesia: Difference between revisions

Non-pharmacologic preanaesthetic interventions include playing cognitive behavioral therapy, music therapy, aromatherapy, hypnosis [[massage]], pre-operative preparation video, and guided imagery relaxation therapy, etc.<ref>{{Cite journal |last1=Wang |first1=Rulin |last2=Huang |first2=Xin |last3=Wang |first3=Yuan |last4=Akbari |first4=Masod |date=2022-04-11 |title=Non-pharmacologic Approaches in Preoperative Anxiety, a Comprehensive Review |journal=Frontiers in Public Health |volume=10 |pages=854673 |doi=10.3389/fpubh.2022.854673 |issn=2296-2565 |pmc=9035831 |pmid=35480569|doi-access=free }}</ref> These techniques are particularly useful for children and patients with [[intellectual disability|intellectual disabilities]]. Minimizing sensory stimulation or distraction by video games may help to reduce anxiety prior to or during induction of general anaesthesia. Larger high-quality studies are needed to confirm the most effective non-pharmacological approaches for reducing this type of anxiety.<ref name="Manyande2015">{{cite journal | vauthors = Manyande A, Cyna AM, Yip P, Chooi C, Middleton P | title = Non-pharmacological interventions for assisting the induction of anaesthesia in children | journal = The Cochrane Database of Systematic Reviews | volume = 2015 | issue = 7 | pages = CD006447 | date = July 2015 | pmid = 26171895 | pmc = 8935979 | doi = 10.1002/14651858.CD006447.pub3 }}</ref> Parental presence during premedication and induction of anaesthesia has not been shown to reduce anxiety in children.<ref name="Manyande2015" /> It is suggested that parents who wish to attend should not be actively discouraged, and parents who prefer not to be present should not be actively encouraged to attend.<ref name="Manyande2015" />

 

{{Use dmy dates|date=January 2019}}Anesthesia has little to no effect on brain function, unless there is an existing brain disruption. Barbiturates, or the drugs used to administer anesthesia do not effect auditory brain stem response.<ref>{{Cite journal |last1=Smith |first1=D.I. |last2=Mills |first2=J.H. |date=May 1989 |title=Anesthesia effects: auditory brain-stem response |url=http://dx.doi.org/10.1016/0013-4694(89)90047-3 |journal=Electroencephalography and Clinical Neurophysiology |volume=72 |issue=5 |pages=422–428 |doi=10.1016/0013-4694(89)90047-3 |pmid=2469566 |issn=0013-4694}}</ref> An example of a brain disruption would be a concussion.<ref>{{Cite journal |last1=Rasouli |first1=Mohammed R. |last2=Kavin |first2=Michelle |last3=Stache |first3=Stephen |last4=Mahla |first4=Michael E. |last5=Schwenk |first5=Eric S. |date=February 2020 |title=Anesthesia for the patient with a recently diagnosed concussion: think about the brain! |journal=Korean Journal of Anesthesiology |volume=73 |issue=1 |pages=3–7 |doi=10.4097/kja.19272 |issn=2005-7563 |pmc=7000285 |pmid=31257815}}</ref> It can be risky and lead to further brain injury if anesthesia is used on a concussed person. Concussions create ionic shifts in the brain that adjust the neuronal transmembrane potential. In order to restore this potential more glucose has to be made to equal the potential that is lost. This can be very dangerous and lead to cell death. This makes the brain very vulnerable in surgery. There are also changes to cerebral blood flow. The injury complicates the oxygen blood flow and supply to the brain.

== Stages of anaesthesia ==

[[Guedel's classification]], described by [[Arthur Ernest Guedel]] in 1937,<ref name = "Hewer_1937" /> describes four stages of anaesthesia. Despite newer anaesthetic agents and delivery techniques, which have led to more rapid onset of—and recovery from—anaesthesia (in some cases bypassing some of the stages entirely), the principles remain.