Cardiac Output NCLEX

Question 1

what is cardiac output

Answer 1

amount of blood ejected from the heart in 1 minute

Question 2

cardiac output equation

Answer 2

CO=HR X SV

Question 3

cardiac output units

Answer 3

ml/min

Question 4

heart rate units

Answer 4

beats per min

Question 5

stroke volume units

Answer 5

ml per beat

Question 6

increased heart rate ____ cardiac output

Answer 6

increases

Question 7

decreased heart rate ____ cardiac output

Answer 7

decreases

Question 8

heart rate is controlled by what node

Answer 8

the SA node/pacemaker of the heart

Question 9

SA node beats per minute?

Answer 9

60-80 beats per minute

Question 10

what are some positive chronotropes that increase heart rate

Answer 10

SNS, Epinephrine, Norepinephrine, Atropine, exercise, age, hormones (T3, T4)

Question 11

what are some negative chronotropes that decreases heart rate

Answer 11

PSNS, digoxin, metotropolol (any beta blocker), hormones

Question 12

what is stroke volume

Answer 12

the amount of blood we push out of our heart per beat

Question 13

increased stroke volume ___ cardiac output

Answer 13

increases

Question 14

decreased stroke volume ____ cardiac output

Answer 14

decreases

Question 15

stroke volume can be divided into what 3 categories

Answer 15

preload, contractility, and afterload

Question 16

what is preload?

Answer 16

this is the amount of stretch/force in the ventricles before contraction

EDV (end diastolic volume, at the end of filling the ventricles right before contraction)

Question 17

how can you increase preload

Answer 17

increase volume/fluids, vasopressors

Question 18

how can you decrease preload

Answer 18

diuretics (peeing a-lot), hemorrhage, blood loss

Question 19

contractility of the heart is dependent upon?

Answer 19

the strength of contraction

(positive ionotrope- increase contractility)

(negative ionotrope- decrease contractility)

Question 20

what is afterload

Answer 20

force the ventricle must push against to eject blood

Question 21

what increases afterload?

Answer 21

vasocontriction (plaque, meds, valve stenosis)- greater force to push against to eject blood

Question 22

increase in afterload ____ stroke volume

Answer 22

decrease ( the heart has to work harder to eject from the ventricles)

Question 23

what causes decreased afterload

Answer 23

vasodilation

Question 24

decrease in afterload ____ stroke volume

Answer 24

increases