Volatile Anesthetics Flashcards
(98 cards)
Advantages of Ether:
Moved through anesthesia stages reliably
Maintained cardiac output and blood pressure
Disadvantages of Ether:
Extremely flammable and explosive, strong emetic properties, airway irritant
What is halogenation? What is the advantage?
A chemical reaction that incorporates a halogen atom (fluoride, bromide, chloride, iodine) into a molecule.
Advantage: increases stability, non-flammable
Halothane: Stored in_____, preserved with _____.
amber bottles, thymol-makes it sticky.
Advantages of Halothane:
Coronary artery vasodilator, non-pungent, non-irritating to respiratory mucosa (Good for inhalation induction), bronchodilator, low PONV, preferred for Tetralogy of Fallot
Disadvantages of Halothane:
Strongest myocardial depressant of all gases, induced arrhythmias, hepatic effects (decreased blood flow causes cell dysfunction), halothane hepatitis
Type 1 vs Type 2 Halothane Hepatitis: Cause: Onset: Labs: Symptoms:
Type 1: mild, from metabolization, genetic factors, reduced liver oxygenation. Onset: with hours Labs: mild elevations in liver enzymes S/S: jaundice
Type 2: severe, , from antibody immune response, binds to hepatocytes, massive necrosis. Onset: high fever 3-14 days after, Labs: elevated bilirubin, elevated liver labs, S/S: high fever, rash, eosinophilia, jaundice, nausea and vomiting, encephalopathy.
50-80% mortality rate with encephalopathy
Advantages of Methoxyflurane:
mild hemodynamic effects, profound muscle relaxant, does not sensitize myocardium to catecholamines, powerful analgesic
Disadvantages of Methoxyflurane:
VERY metabolized (up to 50%), produces free fluoride ions, can cause renal failure, hepatoxicity, pungent
Methoxyflurane
MAC:
B:G:
What does that mean?
0.16% SUPER potent. Have to be very careful.
10-14, high blood solubility, slow onset. Can leech into system/hoses.
What is Penthrox?
Used historically during labor for analgesia. Used in Australia for emergencies, “green whistle”, penthrane inhaler
Advantages of Enflurane:
non-flammable, colorless, non-irritating, stable, can be used in any vaporizer, no impurities, low PONV, rapid induction (compared to ether and methoxyflurane), hemodynamic stability, bronchodilator
Disadvantages of Enflurane:
Produces free fluoride ions (damages kidneys), Ethrane shakes, increases CSF and resistance to CSF flow, can cause EEG to look like tonic clonic seizures
Cyclopropane is stored in _____
Orange cylinders as a pressurized liquid
Cyclopropane:
MAC:
B:G:
- 2%
0. 55 (fast induction)
Advantages of cyclopropane:
non-irritating, blood pressure stability, increased cardiac ouput, no hepatic effects, B:G 0.55 (fast induction), rapid recovery, no delirium
Disadvantages of cyclopropane:
powerful respiratory depressant, bronchoconstrictor, pro-arrhythmic, pro-emetic, EXPLOSIVE
Xenon limitation to use:
Cannot be manufactured-must be extracted from air. Makes it very expensive and limited quantities
Xenon:
MAC:
B:G
71%
.11 (VERY QUICK)
Xenon advantages:
minimal side effects: little to no cardiac depression, maintains cerebral autoregulation, extremely insoluble, no diffuse hypoxia (like N20 can have), NOT a trigger for malignant hyperthermia
Administered with 30% oxygen for surgical anesthesia
Disadvantages of Xenon:
Cost, limited availability, increases cerebral blood flow by 30% (not good for neuro), slight increase in PONV, increases pulmonary resistance
What is MAC?
Minimum Alveolar Concentration. A measure of potency. The concentration at which 50% of the population will not move in response to surgical stimuli. Inversely related to potency and lipid solubility. As MAC goes up, potency goes down and lipid solubility goes down.
What is the MAC of isoflurane?
1.2
What is the MAC of sevoflurane?
1.9
