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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

what is the most commonly used method for measuring CO?

pulmonary artery catheterization (PAC) thermodilution w/ blous injxn of cold fluid