page 360-369

Question 1

https://drive.google.com/open?id=0B8uJUY-tie8GUm5Zb0dwUFRLQkE

Answer 1

https://drive.google.com/open?id=0B8uJUY-tie8GcVV6R2JmN1dPRFE

Question 2

ECG

Answer 2

Records the flow of electrical impulses through the heart.

Question 3

To read ECG:

Answer 3

■ Remember that a single lead corresponds to an anatomic territory.

■ Look at multiple leads together for voltage abnormalities and axis

deviations.

■ Look at a single lead for arrhythmias.

Question 4

https://drive.google.com/open?id=0B8uJUY-tie8GV0h3UGEwUUpadEk

Answer 4

https://drive.google.com/open?id=0B8uJUY-tie8GZEJRSnBnT3h6dFU

Question 5

https://drive.google.com/open?id=0B8uJUY-tie8GYzRXOW52YWY0eGM

Answer 5

https://drive.google.com/open?id=0B8uJUY-tie8GLTJrRHMtU2lzYTA

Question 6

https://drive.google.com/open?id=0B8uJUY-tie8GQUVQYm51djVYM1U

Answer 6

https://drive.google.com/open?id=0B8uJUY-tie8Ga3RGSHFLcV9CbHM

Question 7

https://drive.google.com/open?id=0B8uJUY-tie8GaDFlaWhReks5ZDQ

Answer 7

https://drive.google.com/open?id=0B8uJUY-tie8GUGh6OEQ3WFhEUEE

Question 8

Bainbridge Reflex

Answer 8

■ Stretch of atria (with ↑ blood volume) causes ↑ HR and, therefore, ↑ CO.

■ Mediated by stretch receptors in atria.

Question 9

Receptor cells are sensitive to pressure and stretch.

■ Mediated by vagal (CN X) afferents to the medulla.

■ Efferent loop is slowing of vagal output

Answer 9

Bainbridge Reflex

Question 10

Pumps more blood out of pulmonary system to the systemic system.

■ This helps prevent pulmonary edema.

Answer 10

Bainbridge Reflex

Question 11

Baroreceptor

Answer 11

HR, BP

Question 12

Chemoreceptor

Answer 12

Respiration > vasomotor

Question 13

Baroreceptors

Answer 13

■ Modulate intravascular pressure and HR over a short time period.

■ Activated by ↑ BP.

■ Causes ↓ HR, vasodilation, ↓ BP

Question 14

BARORECEPTOR REFLEX (VALSALVA )

Answer 14

■ ↑ BP/↑ stretch of baroreceptors → ↑ parasympathetic afferent output (CN

IX, X) → medulla → ↑ vagal efferent tone (CN X) (↓ sympathetic tone)

→↓HR, ↓ BP (vasodilation, venodilation) →↓CO.

■ Antagonist to Bainbridge reflex.

Question 15

car sinus

Answer 15

Spindle-shaped dilation of receptors at

he common carotid artery bifurcation

(superior border of thyroid cartilage).

Question 16

Afferent = CN IX.

Answer 16

carotid sinus

Question 17

Afferent = CN X.

Answer 17

Aortic Arch Baroreceptora

Question 18

Receptors in the aortic arch

Answer 18

Aortic Arch Baroreceptora

Question 19

carotid sinus syndrome

Answer 19

Excessive stimulation of both carotid sinuses (eg, convulsive seizures) can

lead to momentary loss of consciousness because of vagal discharge, venodilation,

vasodilation.

Question 20

RESPONSE TO SUDDEN STANDING

Answer 20

↓ BP in brain, upper body sensed by baroreceptors →

■ ↓ parasympathetic firing (CN IX, X); (sympathetic discharge → ↑HR,

↑ conduction velocity, ↑ cardiac contractility, ↑ peripheral resistance ↑

vasoconstriction), ↓ renal blood flow ↑a1 vasocontriction of afferent artery;

b1 on JGA →↑renin →↑angiotensin-II → aldosterone→↑blood back to

heart (↑preload because venoconstriction of large veins) → ↑ CO →

return/maintain BP.

Question 21

HEMORRHAGE OR HYPOVOLEMIA

Answer 21

COMPENSATIONS :

■ Baroreceptor reflex (↑ sympathetic, ↓ parasympathetic tone).

■ ↑ epinephrine from adrenal medulla.

■ ↓ vagal output from medulla (↓ carotid sinus, ↓ aortic baroreceptor firing

Question 22

RAAS (Renin-Angiotensin-Aldosterone system). See renal also.

■ AT-II, aldosterone and increase in TPR

■ AT-II: On efferent arteriole to preserve GFR.

■ Aldosterone: On cortical collecting duct, increase Na+ reabsorption,

K+ excretion, H+ secretion by intercalated cells.

Answer 22

HEMORRHAGE OR HYPOVOLEMIA

Question 23

HEMORRHAGE OR HYPOVOLEMIA

Answer 23

ADH

■ Capillary fluid shift

■ Increases water reabsorption in CCD.

Question 24

Chemoreceptors

Answer 24

■ Detect changes in blood oxygen, carbon dioxide, and hydrogen ion

concentrations.

■ Modulate respiratory center in brain (regulate respiratory activity).

Question 25

Afferent CN IX

Answer 25

Carotid Body

Question 26

Afferent CN X

Answer 26

Aortic Body

Question 27

CHEMORECEPTOR PATHWAY

Answer 27

↑ CO2, ↑ H+, and/or ↓ O2 → stimulates chemoreceptors (carotid, aortic bodies) → ↑ parasympathetic afferent output (CN IX, X) → medulla (respiratory center) → ↑ ventilation (to breathe down CO2) → (↑ BP, ↑ HR secondary to simultaneous secretion of catecholamines from the adrenal medulla). ■ Increase in sensitivity to CO2 and pH when \<60 mm Hg.

Question 28

Mechanisms to meet ↑ demand to muscles during exercise (↑ supply). ■ ↑ CO because ↑ HR and ↑SV.

Answer 28

excersize

Question 29

excersize

Answer 29

Sympathetic nervous system. ■ b2 adrenergic receptors in muscle/pulmonary tree ■ Vasodilate ■ ↑ Blood flow to muscles

Question 30

excersize

Answer 30

b1 receptors in heart ■ ↑ HR ■ ↑ Contraction force (inotropic) (phospholumbar “releasing brake” on SERCA pump) ■ ↑ CO

Question 31

excersize

Answer 31

a1 in other parts of body ■ Vasoconstriction ■ ↑ Arterial pressure

Question 32

excersize

Answer 32

Enhanced venous return (↑ preload). ■ ↓ Venous compliance ■ Pumping effect of the skeletal muscle ■ Vasoconstriction

Question 33

excersize

Answer 33

Local metabolites (released as O2 ↓ 0). ■ Adenosine, CO2, lactic acid ■ Vasodilate: ↓vascular resistance, ↑ blood flow

Question 34

AUTOREGULATION OF BLOOD FLOW

Answer 34

As blood flow ↑ to muscles during exercise, the adenosine is washed out. ■ ↓ adenosine → arterioles and small arteries vasoconstrict → keeping blood flow at a normal rate (in face of ↑arterial pressure).

Question 35

hematocrit

Answer 35

Percentage of RBCs in blood sample. ■ Normal: ■ Male: 44–46. ■ Female: 40–42.

Question 36

Venous Hct is typically higher than arterial Hct because of xxx ■ More yyy in comparison to plasma. CO2 from tissues gets converted by zzz → HCO3 in RBC increases osmotic pressure →water rushes in →RBC greater volume

Answer 36

Venous Hct is typically higher than arterial Hct because of “chloride shift.” ■ More RBC mass in comparison to plasma. CO2 from tissues gets converted by carbonic anhydrase → HCO3 in RBC increases osmotic pressure →water rushes in →RBC greater volume

Question 37

hb conc

Answer 37

Normal: ■ Male: 15–16 g/dL. ■ Female: 13–14 g/dL.

Question 38

Severe anemia:

Answer 38

■ \<7.5 g/dL. ■ Hct = Hb °ø 3.

Question 39

anemia

Answer 39

↓ Hct. ■ ↓ RBC and/or ↓ Hb concentration

Question 40

Consequences of Anemia

Answer 40

■ ↓ oxygen transport in blood. ■ Fatigue, respiratory compensation, cardiac compensation. ■ Hypoxia in the tissues. ■ Causes small arteries and arterioles to dilate (so ↑ blood return to the heart [preload]). ■ Hypoxia in the pulmonary circulation results in vasoconstriction of those vessels (opposite to effect on other body tissues).

Question 41

https://drive.google.com/open?id=0B8uJUY-tie8GbHk3T2wxVnc1bmM

Answer 41

https://drive.google.com/open?id=0B8uJUY-tie8GU0JJR195MTR4QlE

Question 42

https://drive.google.com/open?id=0B8uJUY-tie8GQm9Bbnl1dXZObEE

Answer 42

https://drive.google.com/open?id=0B8uJUY-tie8GRnowaXEtQkhxT28

Question 43

Carbon Monoxide Poisoning

Answer 43

■ CO competes with oxygen for Hb-binding sites and changes allosterics; CO has greater affinity (250°ø) ■ Normal Hb level ■ O2 content ↓ ■ Cherry red cheeks

Question 44

Cyanosise

Answer 44

■ Deoxygenated hemoglobin in tissues gives the skin/mucous membranes a blue tint. ■ Does not occur in severe anemia because you need \>5 g of deoxygenated Hb per 100 mL of blood to appreciat

Question 45

ERYTHROPOIETIN

Answer 45

■ Glycoprotein hormone produced in kidneys ■ ↑ RBC production by bone marrow ■ Acts at the hemocytoblast (pluripotent stem cell)

Question 46

erythpoetin

Answer 46

↓ Erythropoiesis → anemia ■ ↑ Erythropoiesis → polycythemia ■ ↑ Blood viscosity, sluggish blood flow, ie, polycythemia vera (JAK2 mutation downstream of Epo Receptor)

Question 47

Negative Feedback

Answer 47

■ ↓ O2 tension (anoxia/hypoxia) →↑erythropoietin (HIF) ■ ↑ O2→↓erythropoietin

Question 48

Virchow’s Triad

Answer 48

■ Endothelial injury ■ Stasis ■ Hypercoaguability

Question 49

hemostasis

Answer 49

■ Three parts: ■ Vasoconstriction ■ Platelet aggregation/plug (primary)—platelets bind wWF on damaged endothelium ■ Coagulation (secondary)—crosslinking with fibrin meshwork

Question 50

Coagulation Intrinsic and extrinsic pathways

Answer 50

Prothrombin is cleaved to thrombin. ■ Converted by prothrombin activator (Factor Va). ■ Fibrinogen cleaved to fibrin. ■ Converted by thrombin. ■ Fibrin forms the clot and cross-links with the platelets.

Question 51

https://drive.google.com/open?id=0B8uJUY-tie8GbWJ0Z0JSbHlCb1U

Answer 51

https://drive.google.com/open?id=0B8uJUY-tie8GdkpWdTRnN09ZT2c