1 - Vasoconstrictors

Question 1

Alpha 1

Answer 1

widely distributed, multiple organ systems
increase intracellular calcium = constriction (ischemia)
smooth muscle contraction
bronchoconstriction
stops insulin secretion - use glucose (hyperglycemia)
mydriasis - open up eyes
relax GI

Question 2

Alpha 2

Answer 2

precedex, clonidine, CNS - check and balances
picks up norepi, when enough picked up, neg feedback
“agonist activity is antagonistic”
postsynaptic - sedation, decreased SNS outflow, platetl aggregation, decreased BP

Question 3

Beta 1

Answer 3

heart

increased rate, speed of conduction, increased force

Question 4

Beta 2

Answer 4

opposite alpha 1, 
smooth muscle relaxation, peripheral vasodilation
improves oxygen exchange
bronchodilation 
increased insulin secretion
reduced GI mobility
SNS shuts down GI, PNS starts GI

Question 5

Acetylcholine

Answer 5

binds to cholinergic receptors (nicotinic and muscarinic)

acetycholinesterase breaks down Ach

Question 6

ephedrine

Answer 6

direct and indirect effect
direct
indirect - sitm norepi and alpha 1 effects

Question 7

Catecholamine vs sympathomimetic

Answer 7

• OH group on 3 and 4 position of benzyne ring makes catechol
• all sympathomimetics are derived from beta phenylethylamine

Question 8

Catecholamine metabolism

Answer 8

rapid, via enzymes
MAO and COMT
non-catechol (structure) can be broken down by MAO but not COMT
non-natural will not be recycled
**inhibition of MAO will further increase time

Question 9

sulfoconjugation reactions

Answer 9

genetics, changes med metabolism

SULT1A3/SULT1A4 polymorphisms effect phenylephrine

Question 10

Vasoconstrictors

Answer 10

hemodynamic - increase afterload

reflex changes - decreased HR, decreased conduction

Question 11

Vasoconstrictors - non cardiac effects

Answer 11

bronchodilate
glycogenolysis
CNS stim (low lipid solubility)

Question 12

Vasoconstrictor contraindications

Answer 12

LV failure worsens
exacerbate RV failure
decreased RBF
mask hypovolemia

Question 13

low dose epi

Answer 13

1-2 mcg/min, beta 2

decreased SVR, better overall oxygenation

Question 14

intermediate dose epi

Answer 14

4 mcg/min, beta 1

help heart, increased HR, contractility, increased arythmia risk

Question 15

high dose epi

Answer 15

> 10 mcg/min, alpha 1

reflex brady can occur (dt mass increase in SVR)

Question 16

racemic epi

Answer 16

constricts edematous mucosa
increase risk of arythmia
lasts 30-60 mins, monitor for 2 hrs

Question 17

epinephrine

Answer 17

“epi everything” alpha 1, beta 1 and beta 2
most potent activator of alpha 1 receptor
2-10x > potent than NE

Question 18

norepinephrine

Answer 18

alpha 1, some beta 2

reflex brady can occur

Question 19

dopamine

Answer 19

like epi with dopa
beta and alpha
>10 mcg/kg/min alpha starts to dominate

Question 20

ephedrine

Answer 20

epi/norepi mix
hits all receptors
tachyphylaxis - not ideal for infusion

Question 21

phenylephrine

Answer 21

like norepi but less potent, significant alpha, small beta 1

increased preload more than afterload

Question 22

vasopressin

Answer 22

less oxygen consumption than epi, indirect increase in HR, as effective as epi

Question 23

tricyclic antidepress & MOA inhib

Answer 23

prolonged effects d/t increased availability of endogenous norepi

Question 24

cocaine

Answer 24

interferes with reuptake

Question 25

phentolamine

Answer 25

tx for extravasation of catecholamine