Inhaled Anesthetics

Question 1

inhaled anesthetics uses

Answer 1

deepen anesthesia from IV anesthetics

Question 2

boiling points of inhaled anesthetics

Answer 2

NO: low boiling point = gas at RT

volatile anesthetics: high boiling point = liquid at RT

Question 3

volatile anesthetics

Answer 3

fluorinated
enflurane
isoflurane
halothane

Question 4

inhaled anesthetic take-up

Answer 4

gas exchange in alveoli of the lungs

Question 5

solubility fo inhaled anesthetics

Answer 5

halothane = highly soluble in the blood, large amounts needed to saturate, slower onset in brain and long serum half life (fast guy in the pool, passes out at the end holding the flag) 
N2O = less soluble in blood, small amounts cause saturation and faster onset in brain and faster recovery (slow guy in the other lane getting pulled out)

Question 6

blood gas partition coefficient

Answer 6

solubility (partition in the pool.
higher partition coefficient = higher solubility = slower onset
lower partition coefficient = lower solubility = faster onset

Question 7

blood gas partition coefficient of inhaled anesthetics

Answer 7

solubility (partition in the pool.
higher partition coefficient = higher solubility = slower onset
lower partition coefficient = lower solubility = faster onset

Question 8

minimal alveolar concentration (MAC)

Answer 8

percent of anesthetics in the gas mixture that makes 50% of patients unresponsive to painful stimuli (MAC and cheese with one kid unconscious and one not)
corresponds to Ed50 on the graph

Question 9

potency of inhaled anesthetics

Answer 9

minimal concentration necessary for adequate anesthesia

Question 10

relationship between MAC and potency for inhaled anesthetics

Answer 10

inversely proportional

lower mac = higher potency (inverted MAC)

Question 11

side effects of fluorinated anesthetics

Answer 11

myocardial depression = decreased CO, increased arteriole and ventricular pressure and hypotension with
respiratory depression leading to decreased tidal volume minute ventilation and hypercapnia
suppression of mucociliary clearance = post op atelectasis (deflated lungs around a heart on clown )
decrease vascular resistance in the brain = increased cerebral blood flow not desired = increased ICP (cerebral hair on clown)

Question 12

halothane specific side effects

Answer 12

severe liver damage and hepatic necrosis, rarely used in theUS (H = hepatotoxic liver pinata ) 
onset = 2days - 4weeks, get tender, increased LFTs, light microscopy = widespread centrolobular hepatic necrosis
80% mortality and no treatment 
malignant hyperthermia (skeletal muscle hypersensitivity due to defect in ryanodine receptor in the sarcoplasmic reticulum surface, act as Ca channels during contraction, dysfunction = too much Ca and too much ATP and too much heat and muscle damage - rhabdomyalysis and elvated ck (dysfunctional Ryan in banner, guy eating chicken ))

Question 13

enflurane specific side effects

Answer 13

nephrotoxicity (kid hitting guy with a bat in the kidney)

convulsions (shaking pinata)

Question 14

treatment of malignant hyperthermia

Answer 14

dantroline - muscle relaxant acting on ryanodine receptors to prevent Ca (guy near trampoline inhibiting the kid from getting on)