Term
| what organs need most blood? |
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Definition
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Term
| when metabolism increases, flow increases. This is called ___ ___. This happens with exercise and with the brain. |
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Definition
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Term
| coronary arteries penetrate the ___ and originate from the aorta. |
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Definition
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Term
| Systole stops blood flow to the ___ but ___ is still profused. Only during ___ is the endocardium profused. |
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Definition
- endocardium
- epidcardium
- diastole |
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Term
| LV compresses its own blood supply so that flow is low during ___ and high during ___. |
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Definition
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Term
| RV is opposite LV, and has ___ flow during systole, and ___ flow during ___. |
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Definition
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Term
| LV veins have high flow during ___ . |
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Definition
systole
but lv arteries have high flow during diastole |
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Term
| With tachycardia, time in ___ decreases so inside of heart won't get profused. |
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Definition
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Term
| right coronary artery has highest flow in systole |
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Definition
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Term
| extravascular compression is important to what tissues: |
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Definition
| Important in tissues that develop significant tissue pressure or are subjected to gravitational gradients. |
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Term
| contracting muscles cause extrvascular compression |
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Definition
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Term
| With extravascular compression, venous pressure is not relevant, so this condition is sometimes called ___ __. |
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Definition
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Term
| left coronary blood flow is tightly couple to what? |
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Definition
| myocardial oxygen consumption |
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Term
| normal heart has few or no collateral vessels |
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Definition
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Term
| what produces collateral vessels? |
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Definition
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Term
| even though exercise increases coronary blood supply demand, it does not create collaterals b/c there is no ____. |
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Definition
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Term
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Definition
In rigid cranium
Effective pressure: arterial – tissue pressure
Changes in tissue pressure affect flow
Flow tightly coupled to metabolism
Metabolism and flow vary regionally
Flow responds to changes in PO2 and PCO2
Effective autoregulation, protects against hypertension and hypotension
Minor effect of sympathetic stimulation |
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Term
| equation for cerebral profusion pressure: |
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Definition
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Term
| results of increased ICP: |
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Definition
- collapsed veins
- decreases effective CPP
- reduces blood flow |
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Term
| as oxygen partial pressure decreases (hypoxia), cerebral blood flow ___ so vessels ___ in the brain. On the other hand, as carbon dioxide partial pressure increases (hypercapnia), cerebral bloow flow __ and blood vessels dilate. |
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Definition
- increases
- dilate
- increases |
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Term
| decreased oxygen and increased Co2 |
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Definition
| increased cerebral blood flow |
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Term
| normal arterial values of o2 and co2: |
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Definition
pO2= 95 mmHg
pCO2= 40 mmHg |
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Term
Cerebral Circulation Has Very Effective
Pressure-Flow Autoregulation of Blood Flow
Due to Myogenic and/or Metabolic Regulation |
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Definition
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Term
| b/c of the good regulation of cerebral blood flow, even a large drop in ___ ___ __ will only decrease cerebral blood flow slightly. |
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Definition
| - cerebral profusion pressure |
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Term
| with cerebral profusion pressures b/w 70 and 100, cerbral blood flow stays pretty constant. |
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Definition
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Term
| when arterial pressures fall, brain vessels ___ to keep blood flow the same. |
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Definition
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Term
| skeletal muscle circulation: |
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Definition
Large flow reserve
Capillary recruitment
Flow tightly coupled to metabolism
Contraction compresses vasculature and limits flow
During exercise, metabolic vasodilation overrides sympathetic vasoconstriction |
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Term
| DURING EXERCISE THERE IS SYMPATHETIC DYSCHARGE THAT CONSTRICTS VESSELS IN GI TRACT AND KIDNEY TO DECREASE FLOW |
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Definition
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Term
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Definition
Large tissue
Low metabolic rate
Weak metabolic control
Important for temperature control
Strong sympathetic control
Increased sympathetic tone causes vasoconstriction
Reduction of sympathetic tone allows vasodilation
Vasodilation of arterioles and A-V anastomoses promotes heat lose; vasoconstriction conserves heat
Responsive to local paracrine influences during sweating and tissue injury |
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Term
| increased sympth to skin causes: |
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Definition
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Term
| decreased sympth to skin causes: |
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Definition
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Term
| sweating promotes ___ blood flow to skin by causing arterioles to ___. |
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Definition
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Term
VENOUS PLEXUSES ARE CLOSE TO THE SKIN AND THE HOT BLOOD THAT THEY CONTAIN LOSE HEAT, SO NEED TO RETAIN HEAT THEN THE AV ANASTOMOSIS CLOSE.
AS SKIN TEMPERATURE INCREASES BLOOD FLOW INCREASES, AND VICE VERSA. |
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Definition
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