Mock Exam 1 Flashcards
what is included in the afferent limb of the oculocardiac reflex?
long and short ciliary nerves > ciliary ganglion > opthalmic division of trigeminal nerve > gasserian ganglion
what is included in the efferent limb of the oculocardiac reflex?
vagus nerve > SA node
treatment of oculocardiac reflex?
remove stimulus, administer 100% oxygen, administer atropine or glycopyrrolate
what is the heart rate of a transplanted (denervated) heart reliant on?
phase 4 of SA node depolarization (100-120 BPM)
For every 1 unit of PRBC’s transfused, the HGB and HCT should increase by
1g/dL and 2-3% respectively
the two posterior spinal arteries arise from the _____________ and perfuse the ____________ part of the spinal cord
cerebellar arteries, dorsal (sensory)
the anterior spinal artery arises from the _______________ and perfuses the ____________ part of the spinal cord
vertebral arteries, ventral (motor)
SE’s of ARB’s
hyperkalemia
increases lithium absorption by kidneys
increase maternal and fetal mortality (same with ACEI’s)
avoid in renal artery stenosis
what is cardioversion used to treat?
supraventricular and ventricular arrhythmias caused by re entry. This includes, afib, aflutter, AV nodal re entry, tachycardia secondary to pre excitation syndrome
what is the appropriate dose of energy to deliver for the first shock of cardio version for aflutter?
50-100 joules to start, up to 360 joules. remember, you are synchronizing with the R wave
a shock during which time in the cardiac cycle can cause vtach or vfib?
a shock on the t wave (relative refractory period)
how long after a drug eluding stent is placed should a patient wait for elective surgery?
6 months
how long after a bare metal stent is placed should a patient wait for elective surgery?
30 days
what does SSEP monitor?
dorsal (sensory) but not ventral (motor) part of spinal cord
which drugs interfere with SSEP monitoring and how does that manifest?
volatile anesthetics
nitrous oxide
propofol
barbiturates
midazolam
diazepam
decrease amplitude (sensory) and increase latency (time it takes for stimulus to travel from point A to point B)
blood: gas partition coefficient of sevoflurane
0.65
blood: gas partition coefficient of nitrous oxide
0.47
blood: gas partition coefficient of isoflurane
1.4
blood: gas partition coefficient of desflurane
0.42
describe blood: gas partition coefficient
it describes how many parts are in the blood in relation to the alveolus. For example, there are 65 parts in the blood for every 100 parts in the alveolus of sevoflurane (0.65)
what does it mean when the blood: gas partition coefficient is smaller?
the gas isn’t very soluble in the blood. FA equilibrates with FI faster, and therefore the onset is faster
is blood: gas solubility dependent on temperature?
yes, solubility is decreased as temperature is increased (onset is faster)
in the FA/FI curve, name the gases from top to bottom curve
- nitrous oxide
- desflurane
- sevoflurane
- isoflurane (bottom)
how does a right to left shunt affect induction of anesthesia for desflurane?
because the gas has the lowest solubility, much less uptake by the blood happens, and the dilution effect goes “unchecked”. In theory, this would slow induction time of low solubility gases but it really doesn’t.
therapeutic index calculation
median lethal dose/median effective dose
3 chemical components of a local anesthetic
aromatic ring (lipid solubility)
intermediate chain (metabolism and allergic potential)
tertiary amine (water solubility, ionization)
which anesthetics are allergic reactions more common with?
esther anesthetics
what kind of receptor is the opioid receptor?
GPCR
opioids inhibit _____________ and block the conversion of _______ to _________
adenylyl cyclase
ATP to cAMP
increased inositol triphosphate is associated with _________ and _________ receptor agonism
alpha 1 and V1
in the presynaptic nerve, reduced calcium conductance does what?
reduces neurotransmitter release
in the postsynaptic nerve, increased potassium conductance does what?
causes hyperpolarization and makes the neuron less responsive to stimulation
dose range for cocaine and max
1.5-3mg/kg, do not exceed 200mg
what are the symptoms of an anti cholinergic overdose
flushing, mydriasis, dry mouth, confusion, hallucinations, hyperthermia, tachycardia
what is the % of receptor blockade associated with being able to bite on a tongue blade for > 5 seconds?
50% receptor blockade (most sensitive)
what is the % of receptor blockade associated with double burst stimulation without fade?
60% receptor blockade
what is the % of receptor blockade associated with TOF 4/4
70%
what is the % of receptor blockade associated with Vt 5mL/kg
80%
distance for CVL insertion from femoral vein
40cm
distance for CVL insertion from right median basilica vein
40cm
distance for CVL insertion from left median basilica vein
50cm
distance for CVL insertion from right IJ versus left IJ
right: 15
left: 20
the right coronary artery is monitored by leads ______ and supply
II, III, avF
RA, RV, SA, AV, inferior aspect of LV
the LAD is monitored by leads _________ and supply the ________
V3-V5, anterolateral region of LV
the cx is monitored by leads ________ and supply
I, AvL, supplies lateral aspect of LV
recommended bladder width of a BP cuff is what percent of the extremity?
40%
near infrared spectroscopy (NIRS) is a way to assess
venous oxygen saturation (but only in the prefrontal cortex)
adenosine should not be given to patients with
asthma, increases risk of brornchospasm
in piston driven ventilators, the positive pressure relief valve opens at
75cmH2O
in the event of an oxygen pipeline failure, the piston driven ventilator
does not consume tank oxygen (by contrast, a gas driven ventilator does)
are piston driven ventilators fresh gas decoupling ventilators?
yes, which means any change to gas flow, RR, or I:E does not change Vt. By contrast, gas driven ventilators are not decoupled
final products of soda lime include
sodium hydroxide, calcium carbonate
west zone 3 is an
intrapulmonary shunt
west zone 1 is
dead space
brugada syndrome
ion channelopathy in the heart.
dx: RBBB, ST segment elevation in leads V1-V3
common cause of sudden vtach or vfib nocturnal death. more common in males from southeast asia.
long QT syndrome
most common cardiac ion channelopathy. QT interval >440 msec is dx
WPW syndrome
pre excitation syndrome that leads to paroxysmal SVT. short PR interval, delta wave, wide QRS complex
lenegre’s disease
causes defects in his-purkinje system. long pauses, wide QRS complex, bradycardia
explain myasthenia gravis
anti AchR IgG antibodies cause blockage, inactivation, and reduction of post synaptic nicotinic receptors on skeletal muscle.
concentration of pre junctional Ach receptors is unchanged.
cerebral blood flow is directly proportional to
PaCO2
for every 1 change in PaCO2 from 40mmHg, theres a proportional ________ decrease in CBF
1-2mL/100g/min
hydralazine MOA
direct acting vasodilator (after load reducer). MOA unknown but does increase cGMP and relax vascular smooth muscle (arterial>venous)
name the two cutting tip spinal needles
quincke and pitkin
name the three pencil point needles
pencan, whitacre, sprite
drugs that can precipitate a carcinoid crisis
succinylcholine, atracurium, thiopental, epinephrine, norepinephrine, isoproterenol
how to calculate BMI
kg/cm^2=kg/m^2
how to calculate how much bicarb to give
ex) 79kg patient with pH 7.2 and HCO3- 20, want to get to 25
(difference in goal and current x kg x .3) /2
5 x 70 x .3 = 105
105/2 = 53mEq
mannitol dose
.25-1g/kg
fetal risks from anesthesia include
growth restriction, LBW, fetal demise, increased incidence of preterm labor
what kind of drug is phenelzine
MAOI, so dont give any drugs that also increase 5HT or NE (or serotonin. for example, administration of meperidine increases risk of serotonin syndrome)
anti tumor abx
bleomycin and doxorubicin
rank each cause of periop allergic reactions from most to lease
latex
abx
NMB
protamine
- NMB
- latex
- abx
- protamine
