Perfusion - Intro

Question 1

What is perfusion?

Answer 1

Perfusion is the passage of fluid through the circulatory system or lymphatic system to an organ or a tissue, usually referring to the delivery of blood to a capillary bed in tissue. All tissues require an adequate blood supply for health and life

Question 2

heart cells AUTOMATICITY

Answer 2

ability to create an electrical impulse

Question 3

heart cells EXCITABILITY

Answer 3

responds to the created electrical impulse and depolarizes

Question 4

heart cells CONDUCTIVITY

Answer 4

passes the electrical impulse from cell to cell

Question 5

heart cells CONTRACTILITY

Answer 5

cardiac cells respond to electrical impulse and they contract

Question 6

CONDUCTION PATHWAY

Answer 6

SA (sinoatrial) NODE >
Internodal Tract >
RT & LT Atria >
AV (atrioventricular) NODE >
Bundle of HIS >
Bundle Branches >
Purkinje Fibers >
Ventricle 

SAN > IT > ATRIA > AVN > BHIS > BB > PF > Ventricles

Question 7

Systole

Answer 7

contraction of myocardium to vesicles: HIGHEST PRESSURE POINT

Question 8

Diastole

Answer 8

REST PERIOD; ventricles fill with blood

Question 9

Systolic B/P

Answer 9

HIGHEST PRESSURE inserted against ventricle walls when heart is CONTRACTING

Question 10

Diastolic B/P

Answer 10

regular pressure when filling with blood

Question 11

Systolic/Diastolic

Answer 11

HIGHEST pressure/REGULAR pressure

PRESSURE OUT/filling period

Question 12

Mean arterial pressure or MAP

Answer 12

amount of time it takes to perfuse the organs:

desired MAP = 65+ (want to keep all organs perfusing; reduces risk for organ failure)

Question 13

MAP formula

Answer 13

systolic B/P + x2 of diastolic B/P / 3

Question 14

PRELOAD

Answer 14

volume of blood in ventricles at the end of diastole BEFORE next contraction

Question 15

Do you want high preload?

Answer 15

NO

Question 16

What can cause high preload?

Answer 16

HYPOvolemia (LT ventricle)
and
HYPERvolemia (RT ventricle)

Question 17

CONTRACTILITY

Answer 17

strength and vigor of the hearts contractibility during systole

Question 18

what is the frank starling law?

Answer 18

The greater the stretch of the myocardial fibers = the stronger the contraction

Question 19

AFTERLOAD

Answer 19

resistance LT ventricle must overcome to circulate the blood throughout the body

Question 20

Is increased AFTERLOAD good?

Answer 20

No; increased afterload = increased cardiac workload

Question 21

EJECTION FRACTION or EF %

Answer 21

end diastolic volume ejected with each contraction; will never be 100% (good EF% is 50-70%)

Question 22

STROKE VOLUME

Answer 22

amount of blood pumped into the aorta with each contraction of the LT ventricle

Question 23

What is normal cardiac output?

Answer 23

4-8L/min

Question 24

cardiac workload w/ SYMPATHATIC NERVOUS SYSTEM STRESSORS

Answer 24

SYMPATHETIC NERVOUS SYSTEM = FIGHT OR FLIGHT:

INCREASES the rate of the cardiac system

Question 25

cardiac workload w/ PARASYMPATHETIC NERVOUS SYSTEM STRESSORS (or lack of)

Answer 25

PARASYMPATHETIC NERVOUS SYSTEM = REST & DIGEST:

DECREASES the rate of the cardiac system