21-Blood Vessels and Hemodynamics

Question 0

Layers of all blood vessels - 3

Answer 0

Tunica interna - Endothelium, elastic lamina for diffusion
Tunica Media - Smooth muscle, vasoconstriction, elastic lamina
Tunica Externa - contains nerves and blood vessels (vaso vasorum), anchors to surrounding tissue

Question 1

Main blood vessel types - 5

Answer 1

Arteries - take blood away from heart
Arterioles - arteries to capillaries, controls blood pressure
Capillaries - nutrient and gas exchange
Venules - capillary to vein
Veins - take blood to the heart

Question 2

6 Elastic arteries

Answer 2

Aorta
Pulmonary Trunk
Brachiocephalic
Subclavian
Common Carotid
Common iliac

Question 3

Arteriole functions - 4

Answer 3

Regulate blood flow into capillary
Regulate resistance, therefore BP, using sphincter. Vasomotion.
Metarteriole tapers to capillary
Vasoconstriction, vasodilation changes BP

Question 4

More capillaries needed where, amount typically in use at a time

Answer 4

More needed for high metabolic demands (brain, liver, kidney)
25%

Question 5

3 capillary types based on leakiness

Answer 5

Continuous - CNS, lungs, skin, muscle - no proteins cross
Fenestrated - small holes, kidneys, sm. intestines, endocrine glands
Sinusoids - large holes, proteins and RBCs can cross - red marrow, liver, spleen

Question 6

Types of Venules - 2

Answer 6

Postcapillary - allows white blood cell migration, nutrient exchange
Muscular - Reservoir for large amount of blood storage

Question 7

Osmosis - 3 things needed

3 types of pressure

Answer 7

Water movement, through a membrane, from lower to higher solute concentration
Osmotic pressure - due to different solute concentrations, solute Pulls the water
Hydrostatic pressure - Like BP, Pushes the water
Filtration pressure - Osmotic plus Hydrostatic summed

Question 8

Capillary Exchange occurs 3 ways

Answer 8

Diffusion - with concentration gradient
Transcytosis - endocytosis and exocytosis
Bulk Flow - Pressure driven flow, liquids and solutes

Question 9

Bulk Flow parts and process - 7

Answer 9

Blood contains Albumin protein, does not pass membrane
On arteriole side, BP pushes liquids and ions and nutrients to ISF due to Hydrostatic. Can also be some osmotic pushing same way. Filtration.
On veinous side, BP lower, osmotic pressure pushes liquids and “wastes” ISF to blood. Reabsorption.
Left over fluids go into lymph. If lymph cannot handle all, Edema.

Question 10

Systemic Edema - why

Answer 10

Reduced Albumin protein in blood, so Hydrostatic pressure pushes fluids out of blood, but Osmotic pressure does not pull enough back into blood. Lymph is overwhelmed.

Question 11

Blood flow - 2 factors, 3 reasons for one, SVR

Answer 11

Pressure difference
Resistance - lumen size, blood viscosity, vessel length
Systemic Vascular Resistance - arterioles more than other vessels

Question 12

Venous return - 3 factors

Answer 12

Left Ventricle - pressure pushes blood around
Skeletal muscle pumps - legs major factor
Respiratory pump - lungs

Question 13

Varicose veins - 3

Answer 13

Incompetent valves
Physical activity best way to hold off
Great Saphenous Vein likely - little muscle to pump, longest vein in body

Question 14

Circulation Time, and define circulation

Answer 14

Circulation is drop of blood starting at right Atrium, traveling to foot, and back to right Atrium.
One minute.

Question 15

Control of blood pressure and blood flow 1 + 5

Answer 15

Cardiovascular Center in Medulla
Baroreceptors, Chemoreceptors, proprioceptors
Cardiac accelerator nerves (sympathetic)
Vagus Nerve (X) parasympathetic

Question 16

Baroreceptor reflexes - 2

Answer 16

Carotid sinus reflex - glossopharyngeal nerve (IX), for brain pressure
Aortic sinus reflex - systemic pressure, Vagus (X) nerve

Question 17

Chemoreceptors

Answer 17

Excess CO2 - hypercapnia, stimulates CV center

Also input to Respiratory center

Question 18

Hormonal control of blood pressure

Answer 18

Epi and NorEpi increase heart rate and force of contraction

Question 19

Autoregulation of blood pressure - 2 + 2

Answer 19

Physical - warmth causes vasodilation, cold causes vasoconstriction
Vasodilation and Vasoconstriction chemicals
Low O2 causes systemic dilation, pulmonary constriction

Question 20

Pulse rate - normal, low, high rates, names

Answer 20

Normal 60-100 beats per minute
Tachycardia above 100 beats per minute
Bradycardia below 50 beats per minute

Question 21

Shock types - 4+3

Answer 21

Hypovolemic - blood loss, external trauma
Cardiogenic - heart attack - infarction
Vascular - decrease in SVR, anaphylactic (allergy), neurogenic (head/CV trauma), Septic (bacterial toxins)
Obstructive - block, embolism

Question 22

Largest artery - 4 parts

Answer 22

Ascending Aorta - L&R coronary arteries
Arch of the Aorta - Brachiocephalic trunk (R common carotid, R subclavian), L common carotid, L subclavian. R&L vertebral off subclavian
Thoracic Aorta - Descending, to diaphragm
Abdominal Aorta - to R&L common iliac arteries. Branches Celiac trunk, Superior Mesenteric, Inferior Mesenteric.

Question 23

Vertebral arteries - branches from, passes through, forms

Answer 23

Branches off of R&L subclavian arteries
passes through vertebral transverse foramen, through foramen magnum
Unite to form basilar artery

Question 24

Subclavian becomes - 6, posterior versus anterior

Answer 24

Subclavian -> axial -> brachial -> radial, ulnar -> superficial & deep palmar arch. radial feeds posterior ulnar feeds anterior

Question 25

Arteries used for bypass surgery

Answer 25

Posterior intercostal arteries

Question 26

Abdominal aortic branches off of, and what they feed - 7

Answer 26

``` Celiac trunk - foregut Superior mesenteric artery - midgut Inferior mesenteric artery - hindgut Suprarenal arteries (3) - adrenal Renal artery - kidneys Gonadal (testicular or ovarian) - gonads Median sacral artery - sacrum, coccyx ```

Question 27

Continuation of common iliac - 8

Answer 27

Common iliac -> external iliac & internal iliac external iliac -> femoral & deep femoral femoral -> popliteal -> anterior & posterior tibial posterior tibial -> fibular (lateral leg)

Question 28

Exceptions to rule veins follow arteries - 2

Answer 28

Internal Jugular veins drain brain - dural sinuses | Great saphenous veins - medial leg, longest veins, not well supported by muscle, likely to varicose.

Question 29

Renal veins - longer, drains into it - 3

Answer 29

Left is longer, crosses over abdominal aorta | Left renal drains left suprarenal vein, left testicular/ovarian vein, left inferior phrenic vein

Question 30

Hepatic portal circulation -

Answer 30

Splenic & superior mesenteric vein drain into hepatic portal vein into liver for nutrients Hepatic artery feeds along side for O2 L&R hepatic veins leave liver, feed into inferior vena cava

Question 31

Fetal circulation - not functioning, mixing with maternal

Answer 31

Lungs, kidneys, GI tract not functioning | Maternal and fetal blood do not mix. Placenta passes nutrients/wastes between.

Question 32

Fetal circulation - systemic

Answer 32

From internal iliac artery to placenta via umbilical artery Placenta via umbilical vein with O2, two branches -> liver, ductus venosus to inferior vena cava, intermingles O2 and not.

Question 33

Fetal circulation heart - 2

Answer 33

Blood into right atrium crosses to left atrium via foramen ovale Any pumped out right ventricle is passed pulmonary trunk to aorta via ductus arteriosus

Question 34

Changes in infant after umbilical cord tied off - 5

Answer 34

Umbilical artery -> medial umbilical ligament Umbilical vein -> ligamentum teres (round ligament) Ductus venosus -> ligamentum venosum Foramen ovale -> fossa ovalis Ductus arteriosus -> ligamentum arteriosum