CARDIOVASCULAR SYSTEMBLOODHEART

BLOOD VESSELS

BLOOD

Chapter 17

Hematology=the study of blood

Click Here For a Blood Tutorial

CHARACTERISTICS OF BLOOD

Liquid connective tissue4-5 times more viscous than

waterSlightly alkalineWarmer than body temperatureVolume is 4-6 liters

• Men=5-6 L• Women=4-5 L

Salt concentration of .85-.90%

CHARACTERISTICS OF BLOOD

• Heterogeneous mixture

Non-living matrix called PLASMA (55%)

Formed elements (45%)

PLASMA

FORMED ELEMENTS• Erythrocytes= red

blood cells (RBC)

• Leukocytes= white blood cells (WBC)

• Thrombocytes= platelets

FUNCTIONS OF BLOOD• Distribution

Oxygen and carbon dioxideHormonesWastes

• ProtectionClotting mechanismsPhagocytosis and antibody production

• RegulationpHBody temperatureFluid and electrolyte balance

ERYTHROCYTE• CHARACTERISTIC

SMost numerous

formed element with (4.8 to 5.4 million per mm3)

Very flexibleNo nucleusBiconcave disk Life span about 120

daysContains

hemoglobin

HEMOGLOBIN=Transport Pigment

• Oxyhemoglobin

• Deoxyhemoglobin

• Carbaminohemoglobin

Hemoglobin values:• Measured in grams per milliliter

• 14 – 20 g/100 ml in infants

• 13 – 18 g/100 ml in adult males

• 12 – 16 g/100 ml in adult females

ERYTHROPOIESIS=PRODUCTION OF RBC OCCURS IN THE RED BONE MARROW OF FLAT BONES AND IN SOME LONG BONES

Regulation of Erythropoiesis• Hormonal Controls

– Erythropoietin– RBC and Hemoglobin amounts– Availability of oxygen

• Dietary Controls– Adequate amino acids, lipids, and carbs– Iron– Vitamin B12 and folic acid

Regulation of Erythropoiesis

Life Cycle of Erythrocytes

ERYTHROCYTE DISORDERS• ANEMIA

Insufficient #of RBCsHemorrhagic anemia Hemolytic anemia Aplastic anemia

Low hemoglobinPernicious anemia -

macrocytesIron deficiency -

microcytesAbnormal hemoglobin

Thalassemia Sickle cell Anemia

• POLYCYTHEMIAPrimary polycythemiaSecondary polycythemia

Erythrocyte Disorder

HEMATOCRIT

• 47% +/- 5% in males• 45% +/- 5% in females

LEUKOCYTES• CHARACTERISTICS

Less numerous than RBC (less than 1% of blood with normal range of 4800 – 10,800 WBC/ml)

Critical defense cells of the body

Distinct nuclei presentCapable of diapedesisDemonstrate positive

chemotaxisLack hemoglobin

TYPES OF LEUKOCYTES• GRANULOCYTES

Neutrophils (PMNs)EosinophilsBasophils

• AgranulocytesLymphocytesMonocytes

TYPES OF LEUKOCYTES

Mnemonic Devices:• Granulated versus agranulated

– “Every Boy Needs Mommies Love!”

• Relative Quantitates– “Never Let Monkeys Eat Bananas!”

LEUKOPOIESIS

LEUKOCYTE IMBALANCES• Leukocytosis (amounts greater than 11,000

WBC/ml)

• Leukopenia (amounts less than 4,000 WBC/ml)

• LeukemiaAcute leukemiaChronic leukemia

• Infectious Mononucleosis = kissing disease

THROMBOCYTES• CHARACTERISTICS

Involved in hemostasis

Less than half the size of RBC

Numerous (250,000-400,000 per ml3)

Actually cell fragments rather than true cells

Life span is about 5-9 days

FORMATION OF PLATELETS

Regulated by thrombopoietin

STAGES OF BLOOD CLOTTING• Step 1: Vascular spasms

Endothelin Serotonin

• Step 2: Formation of a platelet plug ADP Serotonin Thromboxane A2 von Willebrand factor

STEP 3: COAGULATION• Phase 1: Formation of

prothrombinase (also known as prothrombin activator)

• Phase 2: Conversion of prothrombin to thrombin

• Phase 3: Conversion of soluble fibrinogen into insoluble fibrin

Phase 1: Intrinsic versus Extrinsic Pathways

Phase 2 and 3:

CLOTTING FACTORS

Hemostasis Continued• Clot Retraction

– Also known as Syneresis– Serum (plasma minus clotting factors)

• Repair: PDGF– Stimulates smooth muscle and fibroblast

cells to divide and rebuild the wall• Fibrinolysis

– Plasmin = “clot buster”

Factors Effecting Clot Formation

• Normal coagulation:Normal platelet #sALL clotting factorsVitamin KCalcium ionsTF and PF3

Preventing Undesirable Clotting• Nitric oxide• Prostacyclin (a prostoglandin)• Vitamin E quinone• Heparin• Anti-prothrombin III and Protein C

PLATELET DISORDERS• Thrombus

• Embolus

• Hemophilia

• Thrombocytopenia

• Impaired liver function

• Disseminated Intravascular Coagulation (DIC)

Effects of Drugs on Clotting• Aspirin = antiprostaglandin that inhibits

thromboxane A2

• Heparin = natural anticoagulant produced by basophils and mast cells that inhibits thrombin by enhancing the activity of antithrombin III

• Warfarin = (a.k.a. Coumadin) interfers with the action of vitamin K

Summary of Formed Elements

Summary of Formed Elements

BLOOD TYPING• Blood types are base on the presence of

agglutinogens (antigens) present on the red blood cell surface.

• Also, based on presence of agglutinins (antibodies) in the plasma.

• The ABO and Rh systems are based on antigen-antibody type interactions.

ABO BLOOD GROUPS

BLOOD TYPESBlood Type

Type of Antigen?

Type of Antibody?

Receive?

A A antigen Anti-B A, O

B B antigen Anti-A B, O

AB Both A and B antigens

None A, B, AB, O

O None Both Anti-A and Anti-B

O only

Rhesus FactorBlood Type

Presence of D Antigen?

Type of Antibody?

Receive?

Rh PositiveYes None + and -

Rh Negative No Anti-D - only

BLOOD GROUPS

Type O 45% Type A 42%

Type B 10% Type AB 3%

ABO BLOOD TYPING

BLOOD TYPE TUTORIALTEST YOUR KNOWLEDGE

BLOOD GROUPING DISORDERS

• Transfusion Reaction

BLOOD GROUPING DISORDERS

• Erythroblastosis fetalis