Unit 9 - The Concept of Perfusion

Question 1

Essential function of the cardiovascular and pulmonary systems:

• supply _____ _____ to every cell in the body
• _____ in perfusion affects all human functions

Answer 1

• supply oxygenated blood to every cell in the body

- change in perfusion affects all human functions

Question 2

Where is the heart located

Answer 2

in mediastinum between the vertebral column, sternum; flanked by lungs

Question 3

What is the pericardium

Answer 3

• heart covering

- anchors heart to surrounding structures to form pericardial sac

Question 4

3 layers of the heart wall

Answer 4

• epicardium
• myocardium
• endocardium

Question 5

4 hallow chambers of heart

Answer 5

• 2 atria
• 2 ventricles
• separated by a septum

Question 6

Right atrium:

• _____ deoxygenated blood from veins of body
• superior vena cava _____ blood from body _____ diaphragm
• inferior vena cava _____ blood from the body _____ diaphragm
• coronary sinus _____ blood from heart

Answer 6

• receives deoxygenated blood from veins of body
• superior vena cava returns blood from body above diaphragm
• inferior vena cava returns blood from the body below diaphragm
• coronary sinus drains blood from heart

Question 7

Left atrium:

- receives oxygenated blood from lungs through _____ _____

Answer 7

• receives oxygenated blood from lungs through pulmonary veins

Question 8

Right ventricle:

• receives deoxygenated blood from right atrium and pumps through pulmonary _____ to pulmonary _____ bed for oxygenation
• oxygenated blood travels through pulmonary _____ to left atrium

Answer 8

• receives deoxygenated blood from right atrium and pumps through pulmonary artery to pulmonary capillary bed for oxygenation
• oxygenated blood travels through pulmonary veins to left atrium

Question 9

Left ventricle:

• _____ blood from left atrium
• pumps blood through _____ to general circulation

Answer 9

• receives blood from left atrium

- pumps blood through aorta to general circulation

Question 10

atria separated by _____ _____

Answer 10

atrioventricular valves

Question 11

• Pulmonic valve joins _____ ventricle with pulmonary artery

- aortic valve joins _____ ventricle with aorta

Answer 11

• Pulmonic valve joins right ventricle with pulmonary artery

- aortic valve joins left ventricle with aorta

Question 12

_____ of valves creates heart sounds

Answer 12

closure

Question 13

closure of _____ valve produces first heart sound (S1) or “lub”

Answer 13

atrioventricular (AV)

Question 14

closure of _____ valves produces second heart sound (S2) or “dub”

Answer 14

semilunar

Question 15

heart sounds associated with contraction and relaxation of the heart:

• systole: ventricular _____
• diastole: ventricular _____

Answer 15

• systole: ventricular contraction

- diastole: ventricular relaxation

Question 16

There may be additional heart sounds which indicate _____ _____

Answer 16

damaged tissue

Question 17

Pulmonary circulation:

• _____ side of heart, pulmonary artery pulmonary capillaries pulmonary veins
• _____-pressure system

Answer 17

• right side of heart, pulmonary artery pulmonary capillaries pulmonary veins
• low-pressure system

Question 18

Systemic circulation:

• _____ side of heart, aorta and branches, capillaries of the brain and peripheral tissues, systemic venous system, and vena cava
• _____-pressure system

Answer 18

• Left side of heart, aorta and branches, capillaries of the brain and peripheral tissues, systemic venous system, and vena cava
• high-pressure system

Question 19

Coronary circulation:

• _____ that supply the heart muscle itself
• _____ _____ regulated by aortic pressure, heart rate, heart metabolic activity blood vessel tone

Answer 19

• vessels that supply the heart muscle itself

- blood flow regulated by aortic pressure, heart rate, heart metabolic activity blood vessel tone

Question 20

Transition from fetal to pulmonary circulation:

Flow of blood: placenta -> fetus through _____ _____ to ductus venosus to R atrium

Answer 20

umbilical vein

Question 21

Transition from fetal to pulmonary circulation:

_____ _____ allows blood flow from R atrium to L, then into L ventricle

Answer 21

Foramen ovale

Question 22

Transition from fetal to pulmonary circulation:

blood pumped into _____ and systemic circulation

Answer 22

aorta

Question 23

Transition from fetal to pulmonary circulation:

Systemic vascular resistance:

• _____ after umbilical cord is cut and R atrium pressure falls
• flaps of foramen ovale _____, fibrin deposits seal the opening
• ducuts arteriosus constricts and closes within _____ hours after birth; permanent closure _____-_____ days after birth

Answer 23

increased
close
10-15, 10-21

Question 24

• one heartbeat of contraction and relaxation stroke - volume
• difference between end-diastolic volume and end-systolic volume
• ranges from 60 to 100 mL/beat, averages 70 mL/beat in an adult

Answer 24

cardiac cycle

Question 25

- amount of blood pumped by ventricles into pulmonary and systemic circulation in 1 minute - determined by multiplying stroke volume by heart rate

Answer 25

cardiac output

Question 26

- percent of diastolic volume ejected from heart during systole - stroke volume divided by end-diastolic volume - normal ejection fraction ranges from 50% to 70%

Answer 26

ejection fraction

Question 27

capability of the heart muscle fibers to shorten

Answer 27

contractility

Question 28

the greater the volume, the greater the stretch of the cardiac muscle fibers, and the greater the force with which the fibers contract to accomplish emptying

Answer 28

preload-starling's law

Question 29

force the ventricles overcome to eject blood volume; pressure in the arterial system ahead of the ventricles

Answer 29

afterload

Question 30

sinoatrial node (SA node) located at junction of _____ _____ _____ and _____ _____

Answer 30

superior vena cava and R atrium

Question 31

electrical impulse created by SA node travels to _____ node -> to bundle of his -> to _____ septum -> to _____ fibers in ventricular muscle walls

Answer 31

electrical impulse created by SA node travels to AV node -> to bundle of his -> to interventricular septum -> to purkinje fibers in ventricular muscle walls

Question 32

electrical stimulus creates an _____ _____ -> exchange of _____, _____, and _____ ions across the cell membrane

Answer 32

electrical stimulus creates an action potential -> exchange of sodium, potassium, and calcium ions across the cell membrane

Question 33

depolarization causes a _____ _____

Answer 33

myocardial contraction

Question 34

repolarization is the _____ stage

Answer 34

resting

Question 35

cardiac output determined by _____ _____

Answer 35

heart rate - direct and indirect autonomic stimulation

Question 36

heart affected by both direct and indirect _____ _____ _____ stimulation

Answer 36

autonomic nervous system

Question 37

phase when heart contracts; occurs from two types of ion channels

Answer 37

depolorization

Question 38

process that returns the cell to a resting state

Answer 38

repolarization

Question 39

- Movement of ions across cell membrane causes electrical impulse to stimulate muscle contraction - Produces waveforms on ECG strips

Answer 39

the action potential

Question 40

- Fast sodium channels—occurs in atrial, ventricular muscle cells and Purkinje conduction system - Slow calcium channels—occurs in SA and AV nodes

Answer 40

Depolarization—phase when heart contracts; occurs from two types of ion channels

Question 41

- Refractory period—period of time when myocardial cells resist stimulation; protective mechanism - Supernormal period—occurs after refractory period; a mild stimulus to the cardiac muscle will cause repolarization - Many cardiac dysrhythmias triggered during refractory and supernormal periods

Answer 41

Repolarization—process that returns the cell to a resting state

Question 42

_____ _____ channels—occurs in atrial, ventricular muscle cells and Purkinje conduction system

Answer 42

fast sodium

Question 43

_____ _____ channels—occurs in SA and AV nodes

Answer 43

slow calcium

Question 44

period of time when myocardial cells resist stimulation; protective mechanism

Answer 44

refractory period

Question 45

occurs after refractory period; a mild stimulus to the cardiac muscle will cause repolarization

Answer 45

supernormal period

Question 46

a wave of blood created by contraction of L ventricle

Answer 46

pulse

Question 47

pulse located away from the heart

Answer 47

peripheral

Question 48

a central pulse located at the heart apex; also termed point of maximal impulse or PMI

Answer 48

apical pulse

Question 49

measure of the pressure exerted by blood as it flows through arteries

Answer 49

blood pressure

Question 50

Two blood pressure measures - systolic: ventricles _____ - diastolic: ventricles _____

Answer 50

contract | rest

Question 51

difference between the diastolic and systolic pressures

Answer 51

pulse pressure

Question 52

proportion of RBCs to blood plasma

Answer 52

hct