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HSC 4555 Pathophysiology Exam 2 Review

Chapter 13: Alterations in Oxygen Transport

  • Total Blood Volume

    • Male: 75.5 mL/kg

    • Female: 66.5 mL/kg

  • Plasma Composition

    • Plasma makes up 55-60% of blood volume.

    • Composed of 92% water, 7% plasma proteins.

  • Red Blood Cells (RBCs)

    • True or False: Red blood cells have a nucleus? False

  • Erythropoietin

    • A hormone from the kidney that stimulates erythrocyte production.

  • Hemoglobin Functionality

    • Each hemoglobin (Hb) molecule can bind to 4 oxygen molecules.

    • Hb carries oxygen.

    • Hb production occurs in immature RBCs.

  • Requirements for Hemoglobin Synthesis

    • Requires iron and other nutritional requirements:

    • Proteins

    • Vitamins: B12, Folate, B6, Riboflavin, Niacin, Vitamin E and C.

  • Erythron

    • Red blood cells (RBCs) together with bone marrow precursors = erythron.

  • Kidneys and Hemoglobin Levels

    • A decrease in hemoglobin levels decreases tissue oxygen tension in kidneys.

  • Energy Needs of RBCs

    • RBCs need energy to operate membrane pumps for maintaining ion channels.

  • Digestion of RBCs

    • RBCs are digested by macrophages primarily in the spleen (80-90%) and liver (10-20%).

  • Oxygen Measurement

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

  • Oxygen-Hemoglobin Dissociation Curve

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

  • CO2 Transport Forms

    • CO2 is transported in three forms:

    • Dissolved gas (3%)

    • Bicarbonate ion (HCO3; 75%)

    • Associated with hemoglobin forming carbaminohemoglobin (20%).

  • RBC Disorders

    • Anemia (deficit of RBCs)

    • Polycythemia (excess of RBCs).

  • Aplastic Anemia Pathogenesis

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

  • Chronic Renal Failure and Anemia

    • Causes impaired erythropoietin production (EPO).

  • Anemia and Vitamin Deficiencies

    • Vitamin B12 or Folate deficiency causes disruption in DNA synthesis of blast cells, which produces megaloblasts (macrocytic).

  • Common Cause of Anemia

    • Iron deficiency anemia.

  • Thalassemia

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

  • Clinically Relevant for Hemolytic Newborns

    • Rh incompatibility is more clinically relevant.

  • Definition of Polycythemia

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

  • Types of Polycythemia

    • Polycythemia Vera

    • Secondary Polycythemia

    • Relative Polycythemia (know the difference).

Chapter 15: Alterations in Blood Flow

  • Function of the Circulatory Circuit

    • Functions in absorption and delivery of nutrients, oxygen uptake and delivery, and removal of waste products.

  • Time for Blood Circulation

    • Approximately 1 minute to move 5 liters of blood through the entire circuit.

  • Comparison of Arteries and Veins

    • Arteries contain elastic tissue.

    • Veins contain elastic tissue only in large veins.

  • Intima Layer Functionality

    • Intima layer protrudes into the lumen creating valves that prevent the backflow of blood.

  • Blood Flow Measurement

    • True or False: Blood flow is measured as a given number of liters or milliliters per second, minute, or hour? True

  • Pressure Dynamics

    • Blood moves from areas of higher pressure (arteries) to areas of lower pressure (veins).

    • Greater pressure difference results in greater blood flow (pressure and blood flow are directly proportional).

  • Determinants of Vascular Resistance

    • Vessel length

    • Vessel radius

    • Blood viscosity (know the laws).

  • Vessel Length Impact on Resistance

    • True or False: The longer the blood vessels, the higher the resistance and lower the flow? True

  • Turbulent Flow Generation

    • Turbulent flow is generated at a vessel bifurcation.

  • Clinical Importance in Capillaries

    • Capillary fluid pressure and plasma colloid osmotic pressure are clinically significant.

  • Controls of Blood Flow

    • Extrinsic mechanisms (central)

    • Intrinsic mechanisms (local).

  • Systemic Vascular Resistance Increase Consequence

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

  • Thrombosis Initiation Factors

    • Initiated by alterations in blood flow (slow or turbulent flow), damage or inflammation to the intimal wall of vessel, or emergence of a hypercoagulable state.

  • Types of Arterial Thrombosis

    • Arterial thrombosis reduces flow and increases turbulence, leading to thrombus enlargement and formation of more thrombi.

  • Venous Thrombosis Symptoms

    • True or False: Symptoms may be absent or may be life-threatening secondary to pulmonary embolism? True

  • Major Reason for Arterial Disease

    • Atherosclerosis: hardening of the arteries, leading to hypertension, renal disease, cardiac disease, and peripheral arterial disease.

  • Common Locations for Aneurysms

    • Frequently found in cerebral circulation and thoracic and abdominal aorta.

  • Alterations in Venous Flow Consequences

    • Can be accompanied by edema, venous stasis, inflammation, ulcers, and pain.

  • Lymphedema Statistics

    • True or False: Lymphedema is most common in the U.S because of lymph node removal and radiation? False; it is secondary lymphedema.

Chapter 16: Alterations of Blood Pressure

  • Systemic Arterial Blood Pressure Result

    • Result of cardiac output and the resistance to the ejection of blood from the heart.

  • Systolic vs Diastolic Pressure

    • Systolic pressure: exerted when blood is ejected from ventricles (high).

    • Diastolic pressure: sustained pressure when ventricles relax (lower).

  • Cardiovascular Assessment

    • Mean Arterial Pressure (MAP) is used clinically as part of the assessment.

  • Korotkoff Sounds

    • Phase I: initiation of a clear tapping sound (systolic pressure).

    • Phase V: disappearance of sound (diastolic pressure).

  • Hypertension Guidelines

    • American Heart Association guidelines:

    • Hypertension Grade 1:

      • Systolic: 130-139 mmHg

      • Diastolic: 80-89 mmHg

    • Hypertension Grade 2:

      • Systolic: ≥ 140 mmHg

      • Diastolic: ≥ 90 mmHg

  • Short Term Regulation Mechanism

    • Mediated by the sympathetic branch of the autonomic nervous system.

  • Renin Release Mechanism

    • When stimulated by low arterial pressure, renal cells release renin, which activates angiotensinogen to angiotensin I.

  • Function of Aldosterone

    • A hormone that causes reabsorption of sodium; water passively follows.

  • Most Common Primary Diagnosis

    • Hypertension is the most common primary diagnosis in the U.S.

  • Hypertensive Crisis Description

    • True or False: Hypertensive crisis refers to systolic over 180 and diastolic over 120? True

  • Unknown Causes of Primary Essential Hypertension

    • True or False: Majority of the cases are unknown? True

  • Silent Killer

    • Primary hypertension referred to as the silent killer; damage occurs prior to diagnosis.

  • Hypertensive Emergency Definition

    • A sudden increase in either/or both systolic and diastolic pressure with evidence of end-organ damage.

Chapter 17: Cardiac Function

  • Circulatory System Description

    • Left-sided heart chambers produce the force to propel blood through systemic circulation.

    • Left atrium receives oxygenated blood from lungs via pulmonary veins and delivers it to the left ventricle.

    • Left ventricle pumps oxygenated blood into the aorta, which supplies systemic arteries.

    • Venous blood returns to the right atrium via vena cava.

  • Blood Supply for Heart Muscle

    • Supplied by coronary arteries.

  • Cardiac Cycle Description

    • Each heartbeat includes a period of ventricular contraction (systole) followed by relaxation (diastole).

  • Blood Flow Equation

    • Blood flow = pressure / resistance.

  • Determinants of Coronary Vascular Resistance

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

  • Myocyte Types

    • Two general types:

    • Working cells (for mechanical pumping functions)

    • Electrical cells (for transmitting electrical impulses).

  • Energy Storage in Heart Cells

    • Heart cells store excess ATP as creatine phosphate (CP) using the enzyme creatine kinase (CK).

  • Energy Requirement for Heart Function

    • True or False: 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 ventricle.

Chapter 18: Alterations of Heart Function

  • Cardiac Output (CO)

    • Defined as the amount of blood pumped out of the heart each minute.

  • Stroke Volume (SV)

    • Defined as the amount of blood ejected from the ventricle with each contraction.

  • Determinants of Stroke Volume

    • Includes preload, contractility, and afterload.

  • Coronary Heart Disease (CHD) Prevalence

    • True or False: CHD is responsible for approximately 50% of deaths by CVD? True

  • Characteristics of CHD

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

  • Known Risk Factors for CHD

    • Risk factors include atherosclerosis, hypertension, and dilated cardiomyopathy.

  • Cholesterol Types

    • Defined as good (HDL) and bad (LDL) cholesterol.

  • Lipid Transport

    • Lipids are transported via apoproteins (lipid + protein = lipoprotein).

  • Function of HDL

    • Circulates to tissues, taking up excess free cholesterol, and brings it back to the liver.

  • Function of LDL

    • Absorbed by tissues, with 70% returned to the liver.

  • Atherosclerotic Plaque Formation Initiation

    • Initiated by injury to coronary artery endothelium.

  • Vulnerable vs Stable Plaques

    • Vulnerable plaques: large lipid core, thin cap, high shear stress, inflammation.

    • Stable plaques: more collagen and fibrin, and stable cap.

  • Ischemia Consequences

    • Can result in chronic or acute coronary syndromes.

  • Acute Coronary Syndrome (ACS)

    • True or False: Associated with acute changes in plaque morphology and thrombosis, causing sudden obstruction of coronary artery? True

  • Dysrhythmias and Coronary Syndromes

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

  • Stable Angina Characteristics

    • True or False: Cannot be relieved by rest? False; it can be relieved.

  • Factors Affecting Stable Angina

    • Factors that decrease coronary supply or increase myocardial oxygen demand can upset the balance and lead to ischemia and anginal pain.

  • Myocardial Infarction (MI) Characteristics

    • True or False: Occlusion is complete and the thrombus lasts long enough to cause irreversible damage? True

  • Accurate Diagnosis of ACS

    • Includes signs/symptoms, ECG changes, and serum biomarkers.

  • Chronic Ischemic Cardiomyopathy

    • Refers to a disorder where heart failure develops slowly due to progressive ischemic myocardial damage.

  • Mitral Valve Location

    • Between the left atrium and left ventricle.

  • Function of the Aortic Valve

    • Allows outflow from the left ventricle to the aorta.

  • Stenosis Definition

    • Failure of the valve to open completely results in extra pressure work for the heart.

  • Regurgitation Definition

    • Inability of a valve to close completely results in extra volume work for the heart.

  • Rheumatic Heart Disease Characteristics

    • An acute inflammatory disease that follows infection with group A β-hemolytic streptococci.

  • Infective Endocarditis Definition

    • Involves invasion and colonization of endocardial structures by microorganisms with resulting inflammation and vegetations.

  • Myocarditis Definition

    • True or False: Is an inflammatory disorder of the heart muscle characterized by necrosis and degeneration of myocytes? True

  • Shunt Definition

    • True or False: Right to Left shunt is referred to as an acyanotic defect? False; it is a cyanotic defect.

Chapter 19: Heart Failure and Dysrhythmias: Common Sequelae of Cardiac Disease

  • Heart Failure Definition

    • Heart failure is the inability of the heart to maintain sufficient cardiac output to meet the metabolic demands of tissues and organs.

  • Mortality Rate for HF

    • True or False: 50% of patients die within 5 years of diagnosis? True

  • Common Causes of HF

    • Most common include myocardial ischemia (CHD) followed by hypertension and dilated cardiomyopathy.

  • Systolic Dysfunction Evidence

    • Reduced contractility evidenced by low ejection fraction (EF) and reduced muscular contraction during ventricular systole.

  • Diastolic Dysfunction Hallmark

    • Hallmark includes low cardiac output, congestion, and edema formation with normal ejection fraction (EF).

  • Preload Definition

    • Increased preload is defined as a compensatory mechanism enhancing the myocardium's ability to contract more forcefully.

  • Forward vs Backward Heart Failure

    • Forward failure: insufficient cardiac pumping results in poor cardiac output.

    • Backward failure: congestion of blood behind the pumping chamber.

  • Biventricular Heart Failure

    • True or False: Most often a result of primary left ventricular failure that progresses to right-sided heart failure? True

  • Cardinal Sign of Left HF

    • Pulmonary congestion.

  • Beta Blockers Role

    • True or False: They inhibit sympathetic nervous system effects? True

  • Dysrhythmias Significance

    • Significant for indicating an underlying pathophysiologic disorder and for impairing normal cardiac output.

  • Factors Causing Dysrhythmia

    • Hypoxia, electrolyte imbalance, trauma, inflammation, and drugs.

  • Tachycardia vs Bradycardia

    • Tachycardia: fast heart rate.

    • Bradycardia: slow heart rate.

  • Sinus Arrhythmia vs Sinus Arrest

    • Sinus arrhythmia: degree of variability in heart rate.

    • Sinus arrest: flat trace for a period of a few seconds.

  • Escape Rhythms Association

    • True or False: They are associated with low cardiac output? True