patho exam 2

What is the total blood volume for male and female?

Male: 75.5mL/kg
Female: 66.5mL/kg

Plasma makes up what percent of blood volume?

Plasma makes up 55-60% blood volume

Plasma is composed of what?

92% water, 7% plasma proteins

True or False: Red blood cells have a nucleus.

False.

What is erythropoietin?

hormone secreted by the kidneys that stimulates RBC production

Per one hemoglobin molecule, how many oxygen molecules can it bind to?

4

What do hemoglobin carry?

Oxygen

Where does the production of hemoglobin take place?

immature RBCs

What is required for hemoglobin synthesis?

iron

What nutritional requirements are needed for normal RBC development?

Protein and Vitamins (B12, Folate, B6, Riboflavin, Niacin, Vit E and C)

Red Blood cells + bone marrow precursors =

Erythron

A decrease in hemoglobin decreases what in kidneys?

The tissue oxygen tension in kidneys

What do RBCs need energy for?

to operate membrane pumps for maintaining ion channels

Where do RBC get digested by macrophages?

80-90% in spleen, and 10-20% in liver

True or False: The 3% that is dissolved in plasma is measured as PO2.

True

What does the oxygen-hemoglobin dissociation curve describe?

Describes the relationship between PO2 (pressure) and SO2 (saturation).

What three forms is CO2 transported as?

CO2 is transported as dissolved gas (3%), as bicarbonate ion (HCO;75%), and in association with hemoglobin forming carbaminohemoglobin (20%)

True or False: Carbaminohemoglobin release CO2 in the lungs which we exhale out.

True

What are the RBC disorders?

Anemia (deficit RBC) and polycythemia (excess RBC)

What is the pathogenesis of aplastic anemia?

Stem cell disorder characterized by reduction of hematopoietic tissue, fatty marrow replacement.

What does anemia chronic renal failure cause?

Causes impaired erythropoietin production (EPO)

Anemia in relation to vitamin B12 or Folate deficiency causes a disruption in what?

Disruption in DNA synthesis of blast cells produces megaloblasts (macrocytic)

What is the most common cause of anemia?

iron deficiency anemia

True or False: Thalassemia has increased RBC destruction referred to as hemolysis.

True

For hemolytic newborns, what is clinically relevant?

Rh incompatibility is more clinically relevant

Polycythemia can be defined as?

Excess RBC results in increased blood viscosity which can lead to hypertension

What are the three types of polycythemia?

Polycythemia Vera: Neoplastic transformation of bone marrow stem cells.
Secondary Polycythemia: Caused by chronic hypoxemia with resultant increase in erythropoietin production.
Relative Polycythemia: Caused by dehydration with spurious increase in RBC production.

What does the circulatory circuit do?

Absorption and delivery of nutrients
Oxygen uptake and delivery
Removal of waste products

How long does it take to move 5 liters of blood through the entire circuit?

1 minute

What do arteries contain in comparison to veins?

Arteries contains elastic tissue, whereas veins contain elastic tissue only in large veins.

What does the intima layer function in?

The intima layer protrudes into the lumen creating valves that prevent the backflow of blood.

True or False: Blood flow is measured as a given number of liters or milliliters persecond, minute, or hour

True

Describe how pressure works.

Pressure works in that blood moves from areas of higher pressure (arteries) to an area of lower pressure (veins) which means that greater the pressure difference, the greater the blood flow. Pressure and blood flow are directly proportional!

What are the determinants of vascular resistance?

vessel length, vessel radius, blood viscosity.
LAWS:
Flow = Pressure/Resistance
Blood pressure = flow (cardiac output) x Resistance Resistance = Pressure/Flow

True or False: the longer the blood vessels, the higher the resistance and lower the flow.

True

Turbulent flow is generated where?

vessel bifurcation

What is clinically important in capillaries?

The capillary fluid pressure and plasma colloid osmotic pressure

What are the controls of blood flow?

Extrinsic mechanisms (central) and intrinsic mechanisms (local)

What happens when systemic vascular resistance is increased?

It causes the heart to work harder to meet metabolic demands of the body

Thrombosis is initiated by alterations in what?

Blood flow: slow or turbulent flow; blood vessel wall: damage or inflammation to the intimal wall of vessel; blood coagulability: emergence of a hypercoagulable state

Arterial thrombosis is classified as?

Clot within an artery reduces flow and increases turbulence which enhances thrombus enlargement and formation of more thrombi

True or False: Venous thrombosis symptoms may be absent or maybe life-threatening secondary to pulmonary embolism.

True

What is the major reason for arterial disease?

atherosclerosis (hardening of the arteries)

What is atherosclerosis an underlying condition of?

hypertension , renal disease, cardiac disease, and peripheral arterial disease

Where are aneurysms mostly found?

cerebral circulation and thoracic and abdominal aorta

Alterations in venous flow can be accompanied with?

Accompanied by edema, venous stasis, inflammation, ulcers, and pain

True or False: Lymphedema is most common in the U.S because of lymph node removal,and radiation.

False; secondary lymphedema

Systemic arterial blood pressure is the result of what?

cardiac output
resistance to the ejection of blood from the heart

What is the difference between systolic and diastolic pressure?

Systolic: exerted when blood is ejected from ventricles (high).
Diastolic: sustained pressure when ventricles relax (lower).

What is used clinically as part of cardiovascular assessment?

Mean Arterial Pressure Map (MAP) is the calculated average pressure within the circulatory system.

Out of the Korokthoff sounds, which is classified as the systolic and diastolic pressure.

Systolic: initiation of clear tapping sound
Diastolic: disappearance of sound

According to American Heart Association, what are the guidelines for hypertension grade 1 and 2 for both pressures?

hypertension grade 1: SYSTOLIC (130-139 mmHg) DIASTOLIC (80-89 mmHg)
hypertension grade 2: SYSTOLIC (above 140 mmHg) DIASTOLIC (above 90 mmHg)

What is the short term regulation mechanism mediated by?

sympathetic branch of the autonomic nervous system.

What activates the vasomotor center directly and indirectly?

directly: various stimuli
indirectly: pressure-sensitive baroreceptors (which monitor arterial pressure (MAP) variations)

Beta receptors of the heart increase or decrease heart rate?

increase heart rate.

When the kidney is stimulated by low arterial pressure, what happens?

Release of renin, which activates angiotensinogen to angiotensin 1.

What is the function of the aldosterone?

A hormone that causes absorptions of sodium and water passively follows.

What is the most common primary diagnosis in the U.S?

Hypertension

Describe hypertensive crisis?

systolic over 180
diastolic over 120

True or False: Primary essential hypertension, majority of the cases are caused unknown.

True: Essential hypertension-idiopathic(means cause is unknown)

What does the silent killer refer to?

Primary hypertension is referred to as the silent killer as damage has already occurred to organs before diagnosis

What constitutes a hypertensive emergency?

Hypertensive emergency is a sudden increase in either/or both systolic and diastolic pressure with evidence of end-organ damage.

Describe the Circulatory System.

Left sided heart chambers produce the force to propel blood through the vessels of the systemic (body) circulation. Then, the left atrium receives oxygenated blood from the lungs by the way of pulmonary veins and delivers it to the left ventricle. The oxygenated blood is pumped by the left ventricle into the aorta which supplies the arteries of the systemic circulation. Venous blood is collected from the capillary networks of the body and is returned to the right atrium by the way of vena cava, and blood from the head returns via the inferior vena cava.

The blood supplied to the heart muscle is provided by?

Coronary arteries

What does blood flow equal to?

Blood flow=pressure/resistance

What are the two determinants of coronary vascular resistance?

Artery diameter, and varying degrees of external compression by myocardial contraction and relaxation

What are the two general cardiac myocytes?

The two general types are working cells (mechanical pumping functions) and electrical cells (transmit electrical impulses)

How do the heart cells store excess ATP?

Heart cells are able to store the excess ATP as creatine phosphate (CP) by the enzymecreatine kinase(CK).

True or False: Both cardiac contraction and relaxation require energy

True

Describe the determinants of stroke volume.

Preload: volume of blood in the heart;
Afterload: resistance to ejection from the ventricle

What is cardiac output(CO)?

The amount of blood pumped out of the heart each minute.
Heart rate x Stroke volume.

What is stroke volume(SV)?

amount of blood ejected from the ventricle with each contraction

What are the determinants of stroke volume?

- Volume of blood in heart (preload)
- Resistance to ejection from ventricle (afterload)

True or False: Coronary Heart Disease (CHD) is responsible for approx 50% of deaths by CVD.

True.

What is CHD characterized by?

insufficient delivery of oxygenated blood to the myocardium caused by atherosclerotic coronary arteries

What are the known risk factors for CHD?

- Atherosclerosis: the source of nearly all CHD
- possible microcirculation abnormalities

What is defined as good and bad cholesterol?

LDL=bad
HDL=good

What are lipids transported via?

Apoproteins (lipid+protein=lipoprotein)

What does HDL do?

transport cholesterol from peripheral tissue back to the liver, clearing atheromatous plaque. circulates to the tissues and takes up excess free cholesterol and takes it back to the liver.

What does LDL do?

absorbed by the tissues and 70% returns to the liver

What is atherosclerotic plaque formation initiated by?

injury to coronary artery endothelium

What are the differences between vulnerable and stable plaques?

- Vulnerable: large lipid core, thin cap, high shear stress, Inflammation within.
- Stable: more collagen and fiber, stable cap.

What can ischemia result in?

chronic or acute coronary syndromes

True or False: Ischemia results in oxygen supply insufficient to meet metabolic demands.

True.

The rate of coronary perfusion can be altered by?

1. Large, stable atherosclerotic 2. Acute platelet aggregation and thrombosis 3. Vasospasm 4. Failure of autoregulation by microcirculation 5. Poor perfusion pressure

Describe the pathophysiology of chronic and acute ischemia

Chronic: associated with clinical syndrome of stable angina
Acute: plaque disruption (rupture) and thrombus (clot) formation and results in acute coronary syndrome (unstable angina or MI).

True or False: Acute Coronary Syndrome is associated with acute changes in plaque morphology and thrombosis (clot formation), which causes a sudden obstruction of coronary artery.

True.

True or False: Chronic or acute coronary heart syndromes may precipitate sudden cardiac arrest and associated dysrhythmias.

True.

True or False: Stable angina cannot be relieved by rest.

False, it can be relieved by rest.

What factors of stable angina may upset the balance?

Decreased coronary supply or increase myocardial oxygen demand.

True or False: MI occlusion is complete and the thrombus lasts long enough to cause irreversible damage.

True.

What is an accurate diagnosis of ACS?

signs/symptoms, ECG changes, serum biomarkers

What does chronic ischemic cardiomyopathy refer to?

a disorder in which heart failure develops insidiously (slowly) because of progressive ischemic myocardial damage.

Mitral valve is between which atrium and ventricle?

Left atrium and left ventricle.

What is the function of the aortic valve?

valve allowing outflow from left ventricle to the aorta; prevents backflow of blood into left ventricle.

What is Stenosis?

failure of the valve to open completely results in extra pressure work for the heart; narrowing of valve.

What is regurgitation?

inability of a valve to close completely results in extra volume work for the heart; blood backflows through the valve.

What defines rheumatic heart disease?

Acute inflammatory disease that follows infection with group A β-hemolytic streptococci

What defines infective endocarditis?

Invasion and colonization of endocardial structures by microorganisms with resulting inflammation—vegetations

True or False: Myocarditis is an inflammatory disorder of the heart muscle characterized by necrosis and degeneration of myocytes.

True