Ch.21: Vasodilators (Swift) Flashcards
1
Q
stroke volume
A
volume of blood/heart beat
2
Q
cardiac output =
A
volume of blood/min. CO = SV x HR
3
Q
pre-load
A
volume of blood/end-diastole
4
Q
after-load
A
resistance of eject blood
5
Q
only clinically relevant venodilator
A
nitrates
6
Q
How do nitrates venodilate?
A
form NO and reduce Ca influx into the cell
7
Q
nitrates have long/short half-lives
A
short (rapidly converted to NO)
8
Q
name 2 nitrates
A
nitroglycerin
sodium nitroprusside
9
Q
chars. of nitroglycerin
A
- explosive!
- administered topically or IV
- questionable effect
10
Q
chars. of nitroprusside
A
- balanced vasodilator (venous and arterial)
- decreases systemic BP
- tx CHF
- given at CRI
- tolerance develops
11
Q
side effects of nitrates
A
- hypotension
- rebound hypertension when discontinued
- cyanide poisoning w/ nitroprusside
12
Q
name 3 arteriodilators
A
- nitroprusside
- amlodipine
- hydralazine
13
Q
mech. of arteriodilators
A
-act directly on arterioles to decrease afterload to decrease BP and improve CO
14
Q
chars. of hydralazine
A
- an arteriodilator
- decreases cGMP
- rapid onset of action
- only used to tx CHF if refractory to conventional meds
- causes hypotension if dose high
15
Q
How do Ca channel blockers work?
A
block Ca channels, which slows pacemaker current –> vasodilation, decreased contractility
