Chapter 20 Flashcards
term for the flow of blood through a tissue or an organ
perfusion
where is blood flow the slowest?
capillaries
where is blood flow the fastest?
aorta
the formation of more blood vessles
angiogenesis
the major local factor causing dilation of arterioles
Nitric oxide (NO)
vasodilation
the dilation and relaxation of blood pressure
circulatory shock
Any condition in which blood vessels are inadequately filled and blood cannot circulate normally
Hypovolemic shock
results from large-scale blood loss
Vascular shock
results from extreme vasodilation and decreased peripheral resistance
Cardiogenic shock
results when an inefficient heart cannot sustain adequate circulation
what does long term autoregulation of tissue perfusion depend on?
angiogenesis
how much can muscle blood flow increase by during physical activity?
10x
what can a MAP in the brain below 60 mm Hg cause?
syncope
what is syncope?
fainting
what can a MAP in the brain above 160 cause?
edema
what goes on in the heart during ventricular systole?
Coronary vessels are compressed
Myocardial blood flow ceases
Stored myoglobin supplies sufficient oxygen
what happens to the left over fluid that is not returned to the capillary?
it will be drained by the lymphatic system
5 parts of the Aorta
Ascending Aorta Aortic Arch Descending Aorta Abdominal Aorta Celiac Trunk
largest artery of the body
aorta
what supplies 80% of the brains blood
the internal carotids
5 main veins of the forearm
Radial Ulnar Basilic Cephalic Median Antebrachial
3 veins of the upper arm
Basilic
Brachial
Cephalic
2 deep veins of the lower leg
Anterior Tibial Vein
Posterior Tibial Vein
2 superficial veins of the lower leg
Small saphenous vein
Great saphenous vein
what do the internal and external iliac veins unite to form?
Common iliac Vein
2 types of short-term auto regulation of tissue perfusion
metabolic control
myogenic control
how does metabolic control work?
by making changes to the chemical environment
how does myogenic control work?
by making changes in muscles tone of the arterioles
The Frank Starling Law
The greater the stretch of the cardiac muscle cell, the greater the force of contraction.
why is blood flow through capillaries slow?
because of low pressure gradient along the blood vessel
why is blood flow through capillaries intermittent?
because opening and closing of precapillary sphincters
What type of substance diffuses directly through endothelium membranes?
Lipid-soluble
What type of substance passes through clefts and fenestrations between cells?
Water-soluble
The majority of water and ions move in and out of the capillaries via…?
bulk flow
What are the main forces that determine the direction and amount of flow through capillaries?
hydrostatic pressure and colloid osmotic pressure
2 types of hydrostatic pressures
Capillary hydrostatic pressure and hydrostatic pressure of the interstitial fluid
What is another name for capillary colloid osmotic pressure?
Oncotic pressure
What is capillary colloid osmotic pressure caused by?
Plasma proteins that draw back water into the vessel
What is a late sign of circulatory shock?
Acute hypotension
What are the three branches of the aortic arch?
- Brachiocephalic trunk
- left common carotid artery
- left subclavian artery
the first and shortest part of the Aorta
ascending aorta
What are the two branches of the ascending aorta?
Right and left coronary arteries
longest part of the aorta
descending aorta
What runs downward along the vertebral column before entering the abdominal cavity?
Thoracic aorta
What part of the descending aorta is below the diaphragm?
Abdominal aorta
What are the branches of the celiac trunk?
Common hepatic artery
Splenic artery
Left gastric artery
What does the abdominal aorta support?
Small and large intestines, adrenal glands, kidneys, gonads
What arteries supply the orbits and 80% of the brain?
Internal carotid arteries
where does the thoracic aorta run?
downward along the vertebral column before entering the abdominal
Once the femoral artery has passed through the adductor hiatus into the popliteal fossa it is called what?
Popliteal artery
What does the popliteal artery branch into?
Anterior tibial artery and posterior tibial artery
What artery supplies the lower limbs?
External iliac artery
All blood from areas below the diaphragm are carried back by the…
inferior vena cava
All blood from the areas above the diaphragm is carried back by the…
superior vena cava
Most of the blood from the brain, head, and neck is drained by three veins:
internal jugular vein
vertebral vein
external jugular vein
which veins connect the deep and superficial veins?
perforating veins
how long is the ascending aorta?
2inches
where do most most veins of the brain drain into?
the dural venous sinuses, which in turn drain into the internal jugular veins
Blood from the abdominal and thoracic wall is drained by two veins:
azygos vein and hemiazygos vein
The largest factor that promotes re-absorption of fluids, into blood, from the interstitial fluids
blood osmotic pressure
the most important capillary exchange method
bulk flow
3 branches of the abdominal aorta
celia trunk
superior mesenteric artery
inferior mesenteric artery
which vein drains blood from the radial and ulnar veins, then empties that blood into the axillary vein?
the brachial vein
why do substances tend to leave the bloodsteam at the arterial end of the capillary?
because blood pressure is higher at the arterial end of the capillary
common artery to take pulse of
radial artery
what does the internal iliac artery do?
supplies the pelvic structures
what does the external iliac arter do?
supplies the lower limbs
which vein drains the scalp?
external jugular vein
what does the subclavian vein do?
drains the upper extremities
major artery of the thigh
femoral artery
supplies liver, stomach, and spleen
celiac trunk
arteries that supply the intestines
superior and inferior mesenteric arteries
