Pathophysiology 1 Exam #2

what is the total blood volume for male and female

male: 75.5 ml/kg

female: 66.5 mL/kg

7-8% of body weight

plasma makes up what percent of blood volume

55-60%

plasma is composed of what

93% water, 7% plasma proteins

red blood cells have a nucleus

false

per one hemoglobin how many oxygen molecules can it bind to

4 oxygen per 1 hemoglobin

what do hemoglobin carry

oxygen

where does the production of hemoglobin take place

immature RBC

what is required for hemoglobin synthesis

iron

what nutritional requirements are needed for normal RBC development

protein and vitamins (B6, riboflavin, vitamin C and E, B12)

RBC + bone marrow precursors = 

erythron

a decrease in hemoglobin decreases what in kidneys

decrease tissue oxygen tension kidney secretes erythropoietin = increase RBC increase hemoglobin

what do RBCs need energy for

operating membrane pumps

high K

low Na

even lower Ca

where do RBCs get digested by macrophages

spleen and liver

the 3% that is dissolved in plasma is measured as PO2

True

PaO2 - arterial (80-100 mmHg)

PvO2 - venous (35-40 mmHg)

what does the oxygen hemoglobin dissociation curce describe

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

what three forms is CO2 transported as

dissolved gas (5%)

carbonate ion (75%)

carbaminohemoglobin (20%)

carbaminohemoglobin release CO2 in the lungs which we exhale out

false

RBC disorders

anemia: deficit of RBC

polycythemia: excess of RBC

what is the pathogenesis of aplastic anemia

stem cell disorders characterized by reduction of hematopoietic tissue, fatty marrow replacement

what does anemia chronic renal fialure cause

impaired erythropoietin production

anemia in relation to vitamin B12 or folate deficiency causes a disruption in what

disruption in DNA synthesis of blast cells produces megoblasts (macrophages)

what is the most common cause of anemia

iron deficiency due to inadequate intake, absorption, or loss.

Thalassemia has increased RBC destruction referred to as hemolysis

True

For hemolytic newborns what is clinically relevant

Rh incompatabilitycan lead to hemolytic disease.

polycythemia can be defined as

excess RBC results in increased blood viscosity, leading to clinical smyptoms such as hypertension

what is erythropoietin

hormone from the kidney that stimulates erythrocyte production

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 a spurious increase in RBC production

what does the circulatory circuit do

absorption and delivery of nutrients

oxygen uptake and delivery

removal of waste proucts

how long does it take to move 5 liters of blood through the entire cirtuit

1 minute

what do arteries contain in comparison to veins

arteries: elastic tissue

veins: elastic only in large veins

what does the intima layer function in

protrudes into the lumen creating valves that prevent backflow of blood

Blood flow is measured as a given number of milliliters per second, minute, or hour

true

describe how pressure works

blood moves from areas of high pressure (arteries) to an area of lower pressure (veins)

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, elastic flexibility of the tube and overall blood flow

The longer the blood vessels, the higher the resistance and lower the flow

True

turbulent flow is generated where

at a vessel bifurcation

what is clinically important to capillaries

capillary fluid pressure, plasma colloid osmotic pressure

what are the controls of blood flow

extrinsic mechanisms (central control)

• sympathetic nervous system (SNS)

• a1 adrenergic receptors (noradrenaline)

• b2 adrenergic receptors (epinepherine)

intrinsic mechanisms (local control)

• autoregulation

  • endothelial cells produce nitric oxide (NO)causes dilation by relacing smooth muscle cells

what happens when systemic vascular resistance is increased

heart works harder to meet metabolic demands of the body

thrombosis is initiated by alterations in what

• blood flow: turbulent or slow

• blood vessel wall: damage or inflammation to the internal wall of vessel

  • blood coagulability: emergence of a hypercoagulative state

arterial thrombosis (distal ischemia)

clot within an artery reduces flow and increases turbulence which enhances thromobus enalrgement and formation of more thrombi

decreased distal flow can cause ichemia which can cause arterial acculusio, MI, stroke

venous thrombosis (edemia)

clot in a vein alters venous return impairing the removal of metabolic waste and producing swelling

inflammation that occurs in a vein is called phlebitis and when it is accomplished with a clot, called thrombophlebitis

arterial thrombosis is calssified as

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

Venous thrombosis may be absent or maybe life-threatening secondary to pulmonary embolism

Truuewhat

is the major reason for arterial disease

atherosclerosis  

what is atherosclerosis an underlying consition of

hypertension, renal disease, cardiac disease, peripheral arterial diseasew

where are aneurysms mostly found

cerebral circulation, thoracic and abdominal aorta

alterations in venous flow can be accompanied with

edema, venous stasis, inflammation, ulcers, pain

Lymphedema is most common in the US because of lymph node removal and radiation

false

systemic arterial blood pressure is the result of what

cardiac output and 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 o cardiovascular assessment

mean arterial pressure map (MAP)

calculated average pressure within circulatory system

out of the korokthoff sounds, which is classified as the systolic and diastolic pressure

systolic: initiation of clear tapping sound (phase 1)

diastolic: disappearance of sound (phase V)

What are the guidelines for hypertension grade 1 and 2 for both pressures

grade 1: 130-139 / 80-89

graded 2: 140-149 / 90+

what is the short term regulation mechanism mediated by

rapid adjustments in response to position changes, exercise, emotion and physiological changes

mediate by the sympathetic branch of ANS

what activated the vasomotor center directly and indirectly

directly: various stimuli

indirectly: pressure - sensitive, baroreceptors (monitor 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

The kidney releases renin, activating the renin-angiotensin-aldosterone system (RAAS) to increase blood pressure.

what is the function of the aldosterone

causes reabsorption of sodium and water

what is the most common primary diagnosis in the US

hypertension

describe hypertensive crisis

180+ / 120+

Primary essential hypertension, the majority of cases are caused unknown

True (90% idiopathic)

what does the silent killer refer to

primary hypertension, damage occurred to organs before diagnosis

what consitutes a hypertensive emergency

sudden increase in either or both systolic or diastolic blood pressue with evidence of end-organ damage

describe the circulatory system

lungs

pulmonary veins

left atrium

bicuspid (mitral) valve

left atrium

aortic semilunar valve

aorta

body tissue

capillary system

vena cava

right atrium

tricuspid valve

right ventricle

pulmonary semilunar valve

pulmonary artery

lungs

the blood supplied to the heart muscle is provide by

coronary arteries

describe the cardiac cycle

period of ventricular contraction (systole) followed by relaxation (diastole)

• P wave: atrial depolarization

• QRS complex; ventricular depolarization

  • T wave: ventricular repolarization

what does blood flow equal to

blood flow = pressure / resistance

what are the two determinants of coronary vascular resistance

• artery diameter

  • varying degrees of external compression by myocardial contraction and relaxation

what are the two general cardiac myocytes

1. working cels (mechanical pumping factors)

2. electrical cells (transmit electrical impulses)

how do the heart cells store excess ATP

creatine phosphate by the enzye creatine kinase

both cardiac contraction and relaxation require energy

true

determinants of stroke volume

preload: volume of blood in the heart

afterload: resistance to ejection from the ventricles

what is cardiac output

amount of blood pumped out of the heart per minute

CO - SV * HR

stroke volume

amount of blood ejected from the ventricle with each contraction

determinants of stroke volume

preload, contractility, afterload,

CHD is responsible for approxmately 50% of deaths by CVD

True

What is CHD characterized by

inufficient delivery of oxygenated blood to the myocardium caused by atherosclerosis of coronary arteries

What are the known risk factors for CHD

atherosclerosis

microcirculation abnormalities

what is defined as good and bad cholesterol

LDL bad

HDL good

what are lipids transported as

apoproteins

what does HDL do

circulated the tissue and takes up excess free cholesterol and takes it back to the liver

what does LDL do

absorbed by tissues and 70% is returned to the liver

what is atherosclerosis plaque formation initiated by

injury to coronary artery endothelium

what is the difference between vulnerable and stable plaques

Vulnerable

• large lipid core

• high shear stress

• inflammation within

Stable

• more collagen and fibrin

  • stable cap

what can cause ischemia result in

chronic or acute coronary syndromes

Ischemia results in oxygen supply insufficient to meet metabolic demands

True

rate of coronary perfusion can be altered by

• large stable atherosclerosis

• acute platelet aggregation and thrombosis

• vasospasm

• failure of autoregulation by micronutrition

  • poor perfusion pressure

pathophysiology of chronic and acute ischemia

chronic

• clinical synrome of stable angina

acute

• plaque disturption (rupture) and thrombus (clot) formation

• unstable angina or MI

Acute coronary syndrome is associated with actue changes in plaque morphology and thrombosis (clot formation) which causes a sudden obstruction of coronary artery

True

chronic or acute coronary heart syndromes may precipitate sudden cardiac arrest and associated dysrhythmias

True  

Stable angina cannot be releived by rest

False

what factors of stable angina may upset the balance

decrease coronary supply

increase myocardial oxygen demand

MI occlusion is complete and the thrombus lasts long enough to cause irreversible damage

True

what is an accruate diagnosis of ACS

signs and symptoms

ECG changes

biomarkers (elevated:)

• Myoglobin

  • Troponins I and T (Test of choice)

  • Lactate dehydrogenase

  • Creatine kinase

what does chronic ischemic cardiomyopathy refer to

disorder in hich heart failure develops insidiously (slowly) because of progressive ischemic myocardial damagem

mitral valve is between which atruim and ventricle

left atrium and left ventricle

what is the function of the aortic valve

outflow from left ventricle to aorta

what is stenosis

failure of the valve to open completely which reults in extra pressure work for the heart

regurgitation

insufficiently, the inability of the vale to close completely results in extra volume work for the heart