Anesthetics Flashcards
Part of induction period with depression of RAS and dorsal horn cells
Stage 1
Part of induction where Begins with loss of consciousness, and Depression of cortex
Stage 2
What are some problems with stage 2
Depression of cortex which results in less inhibition of subcortical areas causes Disinhibition can produce several dangerous events:
Hyperreflexia: violent muscular contractions, Irregular respiration, and Vomiting
muscular relaxation with low RR and BP
stage 3
begins with cessation of respiration depression of pons
stage 4 medullary paralysis
as… of adminstration GA increases, recovery takes longer
duration
theory that looked at lipid solubility with GA
Myer Overton
What was basis of GA and lipid membrane theory
GA disrupts lipid membrane causes closure Na channels so less excitation. Issue is that there’s not enough GA per lipid
what are purposes of pre anesthetic medicine
relieve anxiety, prevent secretions, counteract brady, elevate gastric pH (cimetidine)
This GA is used in dentistry but doesn’t relax skeletal muscle and peripheral neuropathy
NO2
volatile liquid GA with respiratory irritation
isoflurane
volatile liquid that yields fluroride toxicity, and seizures
enflurane
this volatile liquid has low B/G solubulity
sevoflurane
IV injection: usual
Primary site of action: RAS
rapid redistribution from brain to other tissues
Uses
Induction of general anesthesia
As sole GA for short procedures without significant pain
thiopental
What are disadvantages of thiopental?
lack of control, poor analgesia, respiratory depressant, poor muscle relaxation
Rapid-acting hypnotic; high lipid solubility, but Not an analgesic.
Minimal effects on HR, cardiac output, peripheral circulation, respiration
Biotransformation: Rapid metabolism in the liver; primarily excreted by kidneys
Etomidate
ADRs of etomidate
myoclonus, hypotension, tachy, tachyapnea
Some degree of analgesic actvity
Uses
Continuous sedation: pts intubated or ventilation / Dx procedures, e.g., colonoscopy
Induction of general anesthesia
Maintenance of general anesthesia in ‘balanced anesthesia’
Propofol
ADRs Propofol
clonic movement, confusion, hypersalivation, bronchospasm
MOA of ketamine
antagonist of NMDA
ADRs of ketamine
Prolonged retention in body
- nightmares
How do CNS depressants, cigarrettes, and antibiotics affect GAs?
depressants can increase effect, unless chronically used will decrease. Cigarettes are inducers. Aminogylcosides/lincosamides/polymixins are additive to paralysis
