Inhalant Anesthetics Flashcards
Which anesthetics are vapors?
Isoflurane
sevoflurane
What is the relationship between anesthetic potency and lipid solubility?
The more lipid soluble the agent the more potent the anesthetic
What is the MOA for inhalants?
Inhibit protein kinase C
Dampen all neuronal activity in the brain @ level of ion channel
Why is vapor pressure important?
Determines type of vaporizer that is required to safely deliver the inhalent
How does the blood:gas solubility affect the rate of change of anesthesia?
The less soluble the anesthetic the more rapid the anesthetic concentration increases in the brain.
Insoluble = fast
What is MAC?
Minimum alveolar concentration
Measure of potency
What decreases MAC?
Other anesthetics used for premed/induction: opioids, alpha 2s, ace, benzos
Decreased body temp, sick or debilitated
What are effects of inhalants on CV function?
Decreased contractility
Decreased cardiac output
Vasodilation, hypotension
Dose dependent
What are the effects of inhalants on respiratory function?
Resp depression
Response to CO2 blunted
Incr PaCO2, decr. PaO2
How are inhalants eliminated from the body?
Primarily respiration
Metabolism to some extent
What is the mechanism by which inhalants induce toxicity?
Metabolic byproducts: fluorite ions
Decrease renal or hepatic blood flow during anesthesia causing damage
What are differences between isoflurane and sevoflurane?
Sevo: decr. vapor pressure, less soluble (faster), higher MAC (less potent), more metabolites
CV and resp effects similar
Which inhalant is the safest?
Isoflurane or sevoflurane
(iso is cheaper)
