inhalation agents, MAC Flashcards
MAC is ___ related to potency
inversely
MAC amnesia = __% MAC
25
MAC awake = __ %MAC
50
MAC intubation = ___% MAC
130
MAC BAR = ___% MAC
150
what age has the greatest MAC requirement
term infant to 6mo
chronic ETOH ___ MAC
increases
which electrolyte increases MAC
na - hypernatremia
hyper or hypothermia increases MAC?
hyper
drugs that increase CNS catecholamines ___ MAC
increase
for every 1 degree drop in C in body temp, MAC decreases by ___%
2-5%
pregnancy __ MAC
decreases
PAo2
38
which electrolyte has no effect on MAC
k
4 factors that have no effect
thyroid gland dysfunction, duration, gender, CO2 (hypo/hypercarbia)
uptake from alveolar space depends on
solubility, cardiac output, and alveolar/venous partial pressure difference
the most important single factor in determining speed of induction and the rate of emergence
solubility
the lower the blood:gas coefficient the __ solubility
lower
the more soluble an agent, the ___ it will be taken up into the pulmonary capillaries and into body tissues
more
blood:gas des
.42
blood:gas n20
.47
blood:gas sevo
.68
blood:gas iso
1.4
a poorly soluble agent has a ___ inhalation and emergence
faster
high cardiac output, ___ rate of rise and induction
slow
low cardiac output, ___ induction
fast
a large alveolar/venous partial pressure difference with an agent ___ uptake and ___ inhalation
enhances, speeds
second gas effect
the ability of a large volume of uptake of a first gas (N2O) to accelerate the rate of rise of the alveolar partial pressure of a concurrently administered companion gas (agent) thus speeding induction
diffusion hypoxia
results from the dilution of alveolar 02 concentration by a large amount of N20 “outgasing” or leaving the pulmonary capillary blood at the conclusion of n2o administration
inhalation agents __ HPV
inhibit
inhalation agents ___ non depolarizing NMB’s
potentiate
N20 ___ PONV
increases
avoid N20 use in
closed gas spaces: PTX, complete bowel obstruction, inner ear, pneumocephalus, air embolism, intraocular bubbles
n20 affect on PVR
increases PVR in patients with pre-exisiting pulm htn.
n20 and fire
nonflammable but an O2 source and supports combustion
N20 inhibits ___ synthesis
methionine. caution in use in pregnancy
long term use of n20 leads to
peripheral neuropathy and megaloblastic anemia
halothane causes a dose dependent decrease in
contractility
halo has ___ preservative
thymol.
pretreat children with ___ for vagal stimulation associated with halo
atropine
which gas sensitizes the heart to catecholamines, dyrhythmogenic, use epi with caution
halo
which gases have a pungent odor
iso/des
which gases cause increase in HR esp when rapidly increasing dose
iso/des
coronary steal syndrome
iso… normal coronaries dilate and stenotic ones dont so blood is shunted away from diseased vessels
which gas is good for inhalation induction
sevo
which gas forms compound A
sevo
with sevo keep flows at at least
2L/min
avoid __ in renal patients
sevo
mac of enflurane
1.68
mac of halo
.75
