Blood and Circulatory System Disorders Flashcards
Chapter 10
Arteries
branch off into arterioles,
They transport oxygenated blood away from the heart
Veins
Return blood to the heart, this has a higher concentration of carbon dioxide and this is going to be exchanged in the lungs for new oxygen
Capillaries
Microcirculation within tissues goes around cells. They are one layer thick and very permeable. They allow oxygen out via tissues, and also they allow carbon dioxide back in to be carried away.
Venules
are the smallest veins, and blood flows from venules into larger veins that eventually return blood to the heart
Pulmonary circulation
Gas exchange in the lungs
Systemic Circulation
Exchange of gases, nutrients, and waste in tissues
Tunica intima
Inside lining. It is made of endothelium( simple squamous epithelium)
Tunica media
Middle layer , smooth muscle layer (Layer that contracts)
Tunica adventitia(Externa)
Connective tissue with fibrocytes , collagen (type I) and elastic fibers
Blood Function
Transport oxygen and nutrients to all tissues
Remove waste products of cellular metabolism
Play a critical role in the body’s defenses/immune system, and
Serve in maintaining body homeostasis
Composition of Blood
Plasma(liquid part)
Plasma proteins( Helps keep it’s concentration of solid & liquid)
Cellular component
Erythrocytes
Leukocytes(immune cells)
Thrombocytes (platelets)
Hematopoiesis
he process of creating blood cells and bone marrow cells, such as red blood cells, white blood cells, platelets, and more
Erythrocytes (Red Blood Cells)
Biconcave flexible discs(Sickle cell anemia loses the disk)
No nucleus in mature state because erythrocytes has to carry a maximum amount of oxygen per cell , so the nucleus isn’t needed anymore. The cell is mature has it’s job and knows what it needs to do. That space is taken up by hemoglobin & oxygen. Also carby hemoglobin to carry carbon dioxide back.
Contains hemoglobin
Globin portion
Heme group
Life span—≈120 days(Then they self destruct)
Erythropoietin produced in the kidney stimulates erythrocyte production.
Blood Clotting—Hemostasis
Three steps:
Vasoconstriction or vascular spasm after injury
Platelet clot
Coagulation mechanism
Plasmin will eventually break down the blood clot.
Clot Formation
Production of prothrombin factor due to tissue damage
Prothrombin or factor II is converted into thrombin
Thrombin converts Fibrinogen (factor I) into fibrin threads
A fibrin mesh forms to trap cells
The clot gradually shrinks or retracts, pulling the edges of damaged tissue closer together and sealing the site
Blood Typing
Blood typing is based on antigens in the plasma membrane of the erythrocytes.
ABO system
Based on the presence or absence of specific antigens
Antibodies in the blood plasma
Rh system
Antigen D in plasma membrane: Rh+
Absence of antigen D: Rh−
Type O
Has no antigens. Has antibodies that will attack the antigen A or the antigen B if it comes into the bloodstream. Type O can only receive their own blood.
Type A
Has the A antigen. Contains Anti-B antibodies in plasma. It can only receive donor blood group O or A.
Type B
Has antigen B. Contains Anti-A antibodies in plasma. Can receive donor blood group B or O.
Type AB
Has both antigen A&B. Has no antibodies in plasma. They can receive donor blood group O , A , B or AB.
Diagnostic Tests (1 of 3)
Complete blood count (CBC)
Includes total red blood cells (RBCs), white blood cells (WBCs), and platelets
Leukocytosis (increased WBCs)
Associated with inflammation or infection
Leukopenia (decreased WBCs)
Associated with some viral infections, radiation, chemotherapy
Increased eosinophils
Common in allergic responses
Differential count for WBCs
Leukocytosis
(increased WBCs)
Associated with inflammation or infection
Leukopenia
(decreased WBCs)
Associated with some viral infections, radiation, chemotherapy
Increased eosinophils
Common in allergic responses
Diagnostic Tests (2 of 3)
Morphology
Observed with blood smears
Shows size, shape, uniformity, maturity of cells
Different types of anemia can be distinguished.
Hematocrit
Percent by volume of cellular elements in blood plasma(How much solid vs liquid)
Hemoglobin
Amount of hemoglobin per unit volume of blood
Mean corpuscular volume (MCV)
Indicates the oxygen-carrying capacity of blood
Diagnostic Tests (3 of 3)
Reticulocyte count
Assessment of bone marrow function
Chemical analysis
Determines serum levels of components, such as iron, vitamin B12, folic acid, cholesterol, urea, glucose
Bleeding time
Measures platelet function
Prothrombin time (PT) and partial thromboplastin time (PTT)
Measure function of various factors in coagulation process
International normalized ratio (INR) is a standardized version.
Blood Therapies (1 of 2)
Whole blood(500ml or less that has all the components), packed red blood cells(Removed a good portion of plasma , mostly cells) , packed platelets(Given to those bleeding , problem clotting)
For severe anemia or thrombocytopenia
Plasma or colloid volume-expanding solutions
To maintain blood volume
Artificial blood products
Compatible with all blood types
None of them can perform all the complex functions of normal whole blood.
Blood Therapies (2 of 2)
(Epoetin alpha)(Stimulate production of red blood cells)
Artificial form of erythropoietin
Before certain surgical procedures
Anemia related to cancer
Chronic renal failure
(Bone marrow or stem cell transplantation)
Close tissue match necessary
Treatment of some cancers
Severe immunodeficiency
Severe blood cell diseases
(Drug treatment)
Aids in the clotting process
The Anemias (1 of 2)
Anemia causes a reduction in oxygen transport.
The basic problem is hemoglobin deficit
Oxygen deficit leads to:
Less energy production in all cells
Cell metabolism and reproduction diminished
Compensation mechanisms
Tachycardia and peripheral vasoconstriction
General signs of anemia
Fatigue, pallor (pale face), dyspnea, tachycardia
The Anemias (2 of 2)
Oxygen deficit leads to:
Decreased regeneration of epithelial cells
The digestive tract becomes inflamed and ulcerated, leading to stomatitis
Inflamed and cracked lips
Dysphasia
Hair and skin may show degenerative changes.
Severe anemia may lead to angina or congestive heart failure (CHF).
Iron Deficiency Anemia
Insufficient iron impairs hemoglobin synthesis.
Microcytic, hypochromic RBCs(They don’t have hemoglobin & are tiny)
Result of low hemoglobin concentration in cells
Very common
Ranges from mild to severe
Occurs in all age groups, but is more common in women of childbearing age
Estimated that one in five women is affected
The proportion increases for pregnant women
Frequently signs of an underlying problem
Causes Of Iron Deficiency Anemia
Dietary intake of iron below minimum requirement
Chronic blood loss
As from bleeding, ulcers, hemorrhoids, cancer
Impaired duodenal absorption of iron
In many disorders, malabsorption syndromes
Severe liver disease
May affect iron absorption as well as storage
Signs and Symptoms Of Iron Deficiency Anemia
The pallor of skin and mucous membranes
Fatigue, lethargy, cold intolerance
Irritability
Degenerative changes
Stomatitis and glossitis
Menstrual irregularities
Delayed healing
Tachycardia, heart palpitations, dyspnea, syncope
Pernicious Anemia: Vitamin B12 Deficiency (1 of 2)
Basic problem is lack of absorption of vitamin B12 because of lack of intrinsic factor
Intrinsic factor secreted by gastric mucosa
Required for intestinal absorption of vitamin B12
Characterized by very large, immature, nucleated erythrocytes
Carry less hemoglobin
Shorter life span