BMD420 Ch.10 - Blood & Circulatory System Disorders

3 Functions of Blood

(1) Transport Oxygen & Nutrients

(2) Waste Removal

(3) Immune System & Homeostasis

Blood is ____ Plasma and ____ Cellular Components.

55%/45%

What are the 2 divisions within the Circulatory System?

- Pulmonary

- Systemic

Around ____ of blood is found within veins.

70%

What 4 things does Venous Blood Flow depend on?

- Muscle Contraction

- Respiration

- Gravity

- Valves

What are the 3 layers of Blood Vessels?

- Tunica intima: Endothelial

- Tunica media: Smooth Muscle

- Tunica externa: Collagen Fibers

Arteries have a thicker ____ than Veins.

tunica media

Vasa vasorum

Small vessels that supply blood to outer part of the larger blood vessels

Autoregulation

The ability of tissues to regulate their own blood supply in response to [CO2] or pH

Angiotensin is a systemic ____.

vasoconstrictor

Capillary walls consist of ____.

a single layer of endothelial cells

Blood pH

7.35-7.45

What are the 3 components of Blood?

- Hematocrit: 45%

- Plasma: 55%

- Buffy Coat: ~1%

Serum

Plasma without proteins and clotting factors

All blood cells originate from ____.

red bone marrow

Dyscrasia

Refers to disorders involving cellular components of Blood

Erythropoietin

Hormone produced by the kidney that stimulates RBC production in response to hypoxia

Hypoxia

Lack of Oxygen

Hemoglobin Makeup

- 2 pairs of polypeptide chains: Globins

- 4 Fe-Containing Heme

Oxyhemoglobin

- Hemoglobin bound to oxygen

- Red

Deoxyhemoglobin

- Hemoglobin without Oxygen

- Bluish

Carbaminohemoglobin

Hemoglobin bound to CO2

Most CO2 is transported in the Blood as ____.

Bicarbonate ion

Lifespan of RBC

120 days

RBCs are broken down in the ____.

Spleen/Liver

In the Spleen/Liver, Globin is broken down into ____.

amino acids

In the Spleen/Liver, Heme is broken down into ____ and ____.

Fe/Bilirubin

Fe is returned to ____.

the bone marrow for RBC production

Excess Fe is stored as ____.

ferritin/hemosiderin

Hemochromatosis

Excess iron deposits throughout the body

Jaundice

Yellowing of the skin due to an excessive buildup of Bilirubin in the Blood

Bilirubin is transported to the ____ where it is ____, then excreted.

Liver/conjugated

Leukopoiesis

Production of WBCs

Colony-Stimulating Factors (CSFs)

Released by macrophages and T-Cells to stimulate growth and differentiation of immature leukocytes in bone marrow

What are the 5 types of Leukocytes?

- Neutrophils

- Lymphocytes

- Monocytes

- Eosinophils

- Basophils

Neutrophils

- Most abundant WBC: 50-60%

- First Leukocyte to respond to tissue damage

- Uses phagocytosis

Basophils

Migrate into tissue to become mast cells that release histamine & heparin

Eosinophils

Granulocyte that combats histamine. Respond to allergic reactions and parasites.

Monocytes

Migrate into tissue to become Macrophages

Thrombocytes

Platelets

What drug can be used to reduce platelet adhesion and lead to increased bleeding?

Acetylsalicylic Acid (Aspirin)

Hemostasis Process

Stoppage of bleeding

(1) Vasoconstriction of injured blood vessel

(2) Thrombocytes adhere to site of injury: Platelet Clot

(3) Coagulation mechanism

Blood Clotting (Coagulation) Process

(1) Damaged tissue and platelets release factors that stimulate reactions producing Prothrombin Activator

(2) Prothrombin (Factor II) is converted into Thrombin

(3) Fibrinogen (Factor I) is converted into Fibrin

(4) Fibrin mesh forms a thromus to trap cells & stop blood flow

(5) Clot gradually shrinks as the injury heals

____ ions are essential for many steps of the clotting process.

Ca2+

Is Hemostasis and Coagulation different?

Yes

Fibrinolysis

Breakdown and removal of a clot

Plasminogen

Inactive form of plasmin

Plasmin

- An enzyme that dissolves the fibrin of blood clots

- Local effect because it is quickly inhibited

Heparin

Anticoagulant that prevents conversion of Prothrombin and Fibrinogen to Thrombin and Fibrin

Blood Typing

ABO System

- A: Anti-B

- B: Anti-A

- AB: Universal Acceptor

- O: Anti-A, Anti-B, Universal Donor

Rh Factor

- Antigen on red blood cells of Rh-positive individuals

- Antigen D

When would Rh Factor become a concern?

When a mother is Rh- (Anti-Rh) and the fetus is Rh+. Anti-Rh bodies would attack RBCs of fetus.

Leukocytosis

Increase in the number of WBCs

Leukopenia

Low WBC Count

An increase in ____ is indicative of allergic response.

Eosinophils

What are some Diagnostic Tests regarding Blood?

- Complete Blood Count (CBC)

- Differential Count

- Blood Smear

- Hematocrit

- Hemoglobin

- Reticulocyte Count

- Bleeding Time

Complete Blood Count

Determines RBC, WBC, and Platelet count

Differential Count

Indicates proportions of WBCs in the Blood

Blood Smear

- Evaluation of the appearance and number of blood cells

- Used in distinguishing anemias

Hematocrit

Percentage of blood volume occupied by red blood cells

Reticulocyte Count

Assessment of bone marrow function by counting the amount of immature RBCs within it

Bleeding Time

Measures platelet function

What are the 6 Blood Therapies?

- Whole blood transfusion: Anemia

- Plasma/Colloidal Volume-Expanding Solutions: TBV

- Artificial Blood Products

- Epoetin alfa

- Bone Marrow/Stem Cell Transplants: Severe

- Blood-Clotting Drugs

Epoetin alfa

Synthetic form of erythropoietin that is used before surgical procedures

Anemia

A condition in which the blood is deficient in red blood cells, in hemoglobin, or in total volume

Oxygen deficit leads to...

- Reduced Cell Metabolism

- Tachycardia & Vasoconstriction: Compensation Mechanisms

- Pallor: Pale Face

- Decreased regeneration of epithelial cells

- Stomatitis

Stomatitis

Inflammation of the mouth due to decreased epithelial cell regeneration

Severe Anemia can lead to ____ or ____.

Angina/Congestive Heart Failure

Iron Deficiency Anemia

Anemia caused by inadequate iron intake; Cannot produce Hemoglobin

Iron Deficiency Anemia is common in ____.

women of childbearing age

Etiology of Iron Deficiency Anemia

- Inadequate Intake

- Blood Loss

- Impaired Duodenal Absorption

- Severe Liver Disease: Storage

Manifestations of Iron-Deficiency Anemia

- Pallor

- Fatigue

- Cold Intolerance

- Stomatitis: Mouth Inflammation

- Menstrual Irregularities

- Tachycardia: Heart Palpitations

Treatment of Iron-Deficiency Anemia

Supplementation of Iron-Rich Products

Pernicious (Megaloblastic) Anemia

- Vitamin B12 deficiency because of a lack of Intrinsic Factor

- Characterized by very large, immature, nucleated RBCs

Intrinsic Factor

A substance produced by the mucosa of the stomach and intestines that is essential for the absorption of vitamin B12

Vitamin B12 is necessary for maintenance and function of ____.

neurons

Significant B12 deficiency will cause symptoms in the ____

PNS - Reversible

Etiology of Pernicious Anemia

Atrophy of gastric mucosa

Manifestations of B12 Deficiency

- Large, red, shiny tongue

- Tingling in limbs

- Digestive discomfort due to Gastric Atrophy

Vitamin B12 Deficiency Diagnostic Tests

- Microscope

- Bone Marrow Exam

- Decreased Vit. B12 Serum

- Hypochlorhydria/Achlorhydria

- Presence of Gastric Atrophy

Treatment of Pernicious Anemia

B12 Injections

Hypochlorhydria/Achlorhydria

Lack of/Absence of stomach acid

Aplastic Anemia

- Failure of blood cell production in the bone marrow

- Typically idiopathic, but not always

Etiology of Aplastic Anemia

- Myelotoxins: Radiation, Drugs

- Viruses

- Genetic Abnormalities

____ indicates Aplastic Anemia.

Pancytopenia

Pancytopenia

Deficiency of all types of blood cells

- Anemia

- Leukopenia

- Thrombocytopenia

What is crucial in treating Aplastic Anemia?

Identification of the cause; Can be life-threatening

Hemolytic Anemia

Reduction in RBCs due to excessive destruction

Etiology of Hemolytic Anemia

- Genetics

- Immune Reaction

- Infections

- Blood Toxins

- Incompatible Blood Transfusion

What are the 2 types of Hemolytic Anemia?

- Sickle Cell

- Thalassemia

Sickle Cell Anemia

- Homozygous recessive genetic disorder that produces abnormal Hb. The altered Hb is unstable and causes conformational changes of RBCs.

- Enlarged RBCs cause obstruction of blood vessels and infarctions across the body

Sickle Cell Anemia exhibits ____ dominance.

incomplete; Produces a hybrid from dominant and recessive traits

HbS

Sickle Cell Hemoglobin

Individuals that are Heterozygous for Sickle Cell Anemia are ____.

protected against Malaria

Hypoxemia

Deficient amount of oxygen in the blood

Sickle Cell Anemia also causes...

- Hyperbilirubinemia

- Jaundice

High Rate of Hemolysis

Manifestations of Sickle Cell Anemia

- Severe Pain: Infarction

- Pallor

- Hyperbilirubinemia

- Splenomegaly

- Delayed Growth

- Congestive Heart Failure

Splenomegaly

Enlargement of the spleen

Sickle Cell Anemia Diagnostic Tests

- Blood Test

- Prenatal DNA Analysis

Sickle Cell Anemia Treatment

- Hydroxyurea

- Folic Acid Supplementation

- Bone Marrow Transplant

- Immunization