5 - Hemodynamics & Blood

Question 1

Blood pressure vs vessels

goodnotes

Answer 1

• pressure falls steadily with distance from L ventricle
• bottom of wave is diastolic pressure, top is systolic

Question 2

Systolic & Diastolic pressure
(label on graph + BP measurement)

Answer 2

systolic: Ventricular contraction (peak of curve)
- first sound heard when measuring

diastolic: V. relaxation, start of aortic pressure jump
- once sound goes silent when measuring

BP is S/D average is 120/80mmHg

Question 3

Pulse pressure
(label on graph + average value)

Answer 3

= diastolic P - systolic P
average is 40mmHg

Question 4

Mean arterial blood pressure
(label on graph + definition)

Answer 4

average pressure during entire cardiac cycle
= diastolic P + 1/3 pulse P
= cardiac output x total peripheral resistance
= HR x SV x TPR

Question 5

Pulse points
(name + location)

Answer 5

• common carotid (neck)
• brachial (upper arm)
• radial (lower arm)
• femoral (thigh)
• popliteal (knee)
• !dorsalis pedis (feetsies)

!may indicate poor bloodflow to lower extremities

Question 6

Factors that increase BP

goodnotes flowchart

Answer 6

Increased cardiac output
- increased heart rate
- down parasympathetic
- UP sympathetic
- increased stroke volume
- UP sympathetic
- UP venous return
- UP BV, muscle pump, resp pump, venoconstriction

Increased systemic vascular resistance
- increased blood viscocity
- UP # of cells (polycythemia)
- increased total blood vessel length
- UP body size (eg: obesity)
- decreased vessel radius (vasoconstriction)

Question 7

Vascular resistance

Answer 7

friction between blood and vessel walls

Increased by:
- small vessel radius
- higher blood viscocity
- longer vessel

arterioles control BP by changing diameter via precapillary sphincters

Question 8

Regulating BP

Answer 8

Neural:
- baroreceptor reflexes
- chemoreceptor reflexes

Hormonal:
- epi & norepi (short term)
- RAA system, ADH, ANP (long term)

ReninAngiotensisAldosterone, AntiDiureticH., AtrialNatrureticPeptide

Question 9

Receptor reflexes

Answer 9

• baro (pressure) & chemo (chemical) receptors
• CN IX & X
• medulla oblongata
• alter sympathetic and parasymp. output

Question 10

Name for what happens when you stand up too fast and faint

Answer 10

orthostatic hypotension

Question 11

Hormonal regulation
(mechanisms)

Answer 11

increased E & NE
- UP HR
- vasoconstrict in skin, GI…
- vasodilate cardiac & skeletal muscle
RAA (see goodnotes)
- angiotensin II: UP vasoconstriction
- aldosterone: UP blood volume
ADH
- UP blood volume & systemic vasocontriction
ANP
- DOWN blood volume & systemic vasodilation

Question 12

Heart failure

Answer 12

Left Sided (input to LA hindered)
- leads to pulmonary edema

Right sided (input to RA hindered)
- leads to pitting edema (around feet and ankles)

Question 13

Functions of blood

Answer 13

• Transportation (chemicals)
• Regulation (pH, temp., water content of cells)
• Protection (clotting, immune)

Question 14

Components of blood

Answer 14

45% erythrocytes (RBC) hematocrit
< 1% leukocytes (WBC) & platelets buffy coat
55% plasma (liquid ext. cell. matrix)
- water, proteins, hormones, chemicals…

RBC & WBC are the formed elements of blood

Question 15

types of blood tests

Answer 15

Complete blood cell count (CBC)
- count types of cells (% and #)
- shapes of cells

Question 16

Methods to obtain blood sample

kill me

Answer 16

• venipuncture (eg. median cubital v.)
• finger or heel stick
• arterial stick (eg. brachial a.)

Question 17

Erythrocytes

Answer 17

• about 7.5 µm
• biconcave disc
• greatest surface area to volume shape
• no nucleus (no DNA)
• anaerobic (no mitochondria)
• contain hemoglobin

Question 18

Hemoglobin

Answer 18

• 4 polypeptide chains (2 alpha, 2 beta)
• each have 1 heme group w/ 1 Fe
• O2 saturation of blood: 97% in lungs, 75% in tissues
• reserves O2 for when needed

Question 19

O2-Hb Dissociation curve

goodnotes

Answer 19

shifts up/left (less oxygen offload)
- triggered by decrease temp, CO2 or increased pH

shifts down/right (more oxygen offload)
- triggered by increase temp, CO2 or decreased pH

Question 20

Erythropoesis

Answer 20

1. pluripotent stem cell
2. myeloid stem cell
3. proerythroblast
4. eject nucleus
5. reticulocyte
6. leave bone marrow & mature in 1-2 days
7. erythrocyte

stimulated by erythropoetin (hormone)

Question 21

Life of an RBC

the next pixar movie

Answer 21

~120 day lifespan
- red bone marrow (erythropoesis)
- circulation (damage, can’t repair)
- die
- breakdown (phagocytosis)

Question 22

Factors affecting EBC production

Answer 22

increased by
- hypoxia (low O2 levels)
- !stenosis in artieries to kidneys
- erythropoetin released by kidneys

!causes kidney to ‘think’ hypoxia is occuring

Question 23

Blood typing (ABO portion)

Answer 23

named by presence of antigens, changed by antibody presence
- type A (A antigens, anti-B antibodies)
- type B (B antigens, anti-A antibodies)
- type AB (neither antibody)
- type O (both antibodies)

can’t have X antigen and anti-X antibody in same bloodstream

Question 24

Testing blood type

Answer 24

treat blood with anti-A or anti-B serum
- agglutination reaction indicates presence of respective antigen
(agg. with anti-A only –> type A blood)

Question 25

Blood typing (non ABO)

Answer 25

Rh blood group
- Rh+ (Rh antigen present)
much more common, in 85% of caucasian women
- Rh- (no Rh antigens)
Rh antibodies typically only develop in Rh- after antigen exposure

Question 26

Hemolytic disease of newborn

Answer 26

• Rh- pregnant & Rh+ fetus
• some fetal RBC’s into maternal circ. (typically occurs during delivery)
• develop Rh antibodies between pregnancies
• second Rh+ fetus
• maternal RBC into fetal circ.
• antibodies cause hemolytic disease of newborn

Question 27

How to prevent hemolytic disease of newborn

Answer 27

• test finds pregnant person is Rh-
• treated with anti-Rh antibodies immediately after delivery
• artificial antibodies prevent future production by preggers one