Flashcards in cardiac output Deck (18):
1
CO = ?
SV x HR
2
normal CO?
5 L/min in resting adult
can vary based on metabolism, age, body size
3
what is a better way to measure volume of blood ejected from heart?
cardiac index
4
cardiac index =?
volume of blood ejected from heart per unit time per unit of body surface area
5
normal cardiac index?
3 L/min/sq of S.A
6
what is the SV?
volume of blood ejected by ventricle during each contraction
7
determinants of SV
1. end-diastolic volume/ preload
2. ventricular contractility
3. afterload
8
tension exerted on cardiac ventricular muscle when it begins to contract
preload
9
the pressure that the ventricle has to win to produce a SV?
after load
10
what determines after load?
1. ventricular outflow tract
2. aortic valve fxn
3. peripheral arterial resistance/ bp
11
intra-ventricular volumer at the end of systole; indicator of systolic fxn
end-systolic volume
12
what determines ESV?
1. preload
2. ventricular contractility
3. after load
13
what is a length dependent activation of the heart (when the force of ventricular contraction is a fxn of the ventricular end diastolic length of the cardiac muscle_
frank starling law of the heart
14
if keep preload & contractility constant, and increase afterload, what happens to SV?
SV decreases
15
what is the ANREP effect?
when the aortic perssure is elevated abruptly, a positive inotropic effects follows within 1-2 min
16
when you incr the hr (the rate of stimulation), it incr contraction - what is this phenomenon called?
bowditch staircase phenomenon
17
effect of HR on CO is ________
rate-dependent
18