Hemodynamics and Blood-05

Question 1

blood pressure

Answer 1

the pressure that is exerted by the blood against the walls of blood vessels and measured in mmH, mostly generated by ventricular contraction

Question 2

pulse pressure (PP)

Answer 2

difference between systolic and diastolic pressure

Question 3

mean arterial blood pressure

Answer 3

the average pressure during the entire cardiac cycle, mean ABP = diastolic + 1/3(PP); significance is CO x TPR, your BP is a function of how much blood you push out of the heart per min. and how much resistance the heart is working against

Question 4

what factors affect blood pressure?

Answer 4

cardiac output, blood volume, peripheral vascular resistance

Question 5

pressure

Answer 5

flow x resistance

Question 6

flow

Answer 6

pressure/resistance

Question 7

vascular resistance

Answer 7

friction b/w blood and the vessel walls

Question 8

factors affecting vascular resistance

Answer 8

blood vessel radius, blood viscosity, blood vessel length

Question 9

in what ways is blood pressure regulated?

Answer 9

neural, via baro and chemoreceptors, and hormonal, via E and NE, ADH, atrial natriuretic peptide (ANP), renin-angiotensin-aldosterone pathway (RAA)

Question 10

how is blood pressure regulated in the short-term?

Answer 10

neurally, sometimes hormonally

Question 11

how is blood pressure regulated in the long-term?

Answer 11

hormonally

Question 12

how do baroreceptors correct for hypotension?

Answer 12

upon detecting BP decrease, sensory info. travels to medulla oblongata to increase sympathetic outputs by increasing CO (SV & HR) and TPR; message sent to pacemaker cells and heart wall

Question 13

how do baroreceptors correct for hypertension?

Answer 13

upon detecting BP increase, sensory info. travels to medulla oblongata to increase parasympathetic outputs by decreasing HR, message sent to pacemaker cells

Question 14

short-term hormonal regulation

Answer 14

activation of sympathetic nervous system releases epinephrine and norepinephrine from the adrenal glands (goes directly into blood and stimulates target organs)

Question 15

ADH (vasopressin)

Answer 15

release from post. pit. in response to dehydration or decreased blood vol., increases renal water retention and systemic vasoconstriction to increase BP

Question 16

atrial natriuretic peptide (ANP)

Answer 16

released by atrial cells when they’re stretched out too much, causes vasodilation, promotes renal loss of salt/water and lowers BP

Question 17

RAA system

Answer 17

regulates BP; low circulating renal blood volume causes renin to be released from kidney which stimulates formation of angiotensin I which converts to angiotensin II to increase BP by vasoconstriction and increased aldosterone production (promotes water reabsorption and secretion of K+ and H+ into urine

Question 18

shock

Answer 18

the failure of the CV system to deliver enough oxygen and nutrients to meet tissue demand

Question 19

components of shock

Answer 19

inadequate perfusion or increased demand, cells forced to switch to anaerobic respiration, lactic acid build up, cells and tissues become damaged and die

Question 20

what are some compensatory mechanisms of shock?

Answer 20

activate RAA system, secrete ADH, activate SNS, release of local vasodilators

Question 21

heart failure

Answer 21

a chronic condition in which the heart is unable to pump out all of the blood that it receives

Question 22

what is a major sign of left-sided heart failure?

Answer 22

pulmonary edema (crackles in the lung fields); LV receives blood from the LA which receives blood from the pulmonary veins

Question 23

what is a major sign of right-sided heart failure?

Answer 23

tissue edema; fluid sits in veins and venules, increases hydrostatic pressure within vessels, therefore more fluid leaking out into tissues

Question 24

what are the functions of blood?

Answer 24

transportation, regulation and protection

Question 25

components of blood

Answer 25

plasma and formed elements

Question 26

what type of tissue is blood?

Answer 26

connective tissue

Question 27

complete blood count (CBC)

Answer 27

comprehensive blood test that includes red blood cell count (RBC), white blood cell count (WBC), hemoglobin (Hgb), hematocrit (Hct), white blood cell differential, and platelet count + morphology

Question 28

how to obtain a venous blood sample?

Answer 28

venipuncture with a vacutainer

Question 29

how to obtain ABG?

Answer 29

arterial stick at the brachail artery

Question 30

how to obtain a blood sample from the capillaries or to check blood glucose?

Answer 30

finger/heel stick

Question 31

red blood cells

Answer 31

biconcave disc with greatest SA:V ratio, has strong and flexible membrane, no nucleus, lacks mitochondria, has hemoglobin

Question 32

hemoglobin

Answer 32

iron-containing protein in red blood cells that carries oxygen for delivery to cells; each can bind 4 O2 molecules, and it also works as a tissue oxygen buffer system

Question 33

erythropoeisis

Answer 33

formation of RBCs

Question 34

what occurs if the rate of RBC destruction exceeds the rate of production?

Answer 34

anemia

Question 35

hemoglobin components

Answer 35

most are recylced; the globular part is broken down into a.a.’s to make new proteins, and the non-protein heme is toxic waste that is discarded (bilirubin), iron is saved to make new hemoglobin

Question 36

bilirubin

Answer 36

pigment released by the liver in bile; accumulation causes jaundice as a result of liver damage

Question 37

what happens to RBC count in response to hypoxia?

Answer 37

decreased O2 levels signal erythropoetin release, stimulating the red bone marrow to produce more RBC to increase O2 carrying capacity

Question 38

what can occur with too much RBCs in the blood?

Answer 38

increased blood viscosity which increases the risk of heart attack and stroke

Question 39

what factors should be considered in one’s RBC count and O2 levels?

Answer 39

altitude, blood donation, kidney failure, renal artery stenosis