Isoflurane Flashcards
The constant for the Meyer-Overton equation is __ atmospheres
1.8
The lower the MAC necessary for anesthesia, the __ the potency and the __ the oil:gas partition coefficient.
Greater potency
Higher oil:gas partition coefficient
The oil:gas partition coefficient for Iso is __
97
Again, the higher the Oil-gas partition coefficient, the __ the lipid solubility AND potency
Greater
Iso causes immobility to painful stimuli by enhancing __ ion channels and reducing spinal neuron action potentials via __ and ___ receptor mediation.
K+ channels
Glycine and GABAa receptor mediation
The effects of general anesthetics are very __ , many different receptors in both brain and spinal cord
Diffuse
Receptors involved in the spinal cord include __, 5-hydroxytriptamine, __, NMDA, __, and AMPA
Glycine, 5-hydroxytriptamine, Na+, NMDA, K+, and AMPA
Receptors involved in the brain include Kainate, ___, ___, alpha-2, 5ht3, ___
Kainate, GABA, OPIOID, alpha-2, 5ht3, ACETYLCHOLINE
CFC’s are colorless, odorless, nonflammable, noncorrosive gases or liquids. CFC stands for __
Chlorine
Fluorine
Carbon
If iso were entirely fluorinated it would be a non-___
Immobilizer
Racemic mixtures are __/__ mixes of stereoisomers
50/50
What is the BLOOD-gas partition coefficient of iso?
1.46
What is the vapor pressure of iso?
238
Is iso stable in moist soda lime and available generically?
Is it ok to use with a closed circuit?
YES
Yes
Stable in soda lime means it doesn’t make any bad compounds.
Does iso need a preservative? Does it produce compound A or carbon monoxide?
No
No
No
What is the metabolism rate of iso?
0.2%
Iso is the only molecule with the __ atom
Chlorine
Sevo is the molecule with ___ fluorines
Seven
Des is the molecule with NO chlorines and __ fluorines
Six
Does iso produce skeletal muscle relaxation?
Yes
MAC is completely ___ of the length of the anesthetic
Independent
Length of anesthesia DOES NOT increase or decrease MAC requirements.
What is the MAC for iso for age 36-49?
1.2
Dose of iso needed to produce apnea is around __ mac
2
Iso causes airway irritation around __ mac
1
Can you use an LMA with iso?
Yes
How much iso MAC for a deep extubation?
0.85 MAC
Iso causes peripheral vaso___ and __ body temps.
Vasodilation
Decreases body temps
Does iso alter the hypoxia pulmonary vasoconstriction? HPV
Yes
Does iso predispose arrhythmias or protect against them?
Would your electrophysiologist want you to use iso?
Protects against them, anti arrhythmic
You EP would NOT want you to use iso because of that
Iso abolishes baroreflexes around __ mac
1
Iso cause circulatory collapse around __ mac
3
Is iso implicated in “coronary steal”
No
Will iso adversely affect renal or hepatic perfusion?
No
Will iso raise your ICP?
Yes
Can iso prolong the effects of muscle relaxants and thus allow a lower dose of vec to be used?
Yes
Can iso trigger MH?
Yes
What is uncoupling?
When iso decreases cerebral metabolic requirements but increases cerebral blood flow
Can iso cause neuro degeneration in kids?
Yes
Does iso contribute to post op cognitive dysfunction and accelerate Alzheimer’s?
Yes
Iso only undergoes 0.2% metabolism. What pathway is used and what are the outcomes?
Cytochrome p450 Trifluoroacetic acid Free fluoride Co2 Water
Can iso cause hepatitis? What is the mediator?
Yes
Chlorine > Trifluoroacetic acid
How much does iso cost compared to sevo and des?
1/5 or 20% of the cost of sevo and des
