APCVS Week 3 - Blood Components & Types

Course Information

• Course: APCVS
• Week: 3
• Chapter: 24

Objectives

• List and describe components of blood
• Discuss blood types (ABO/Rh)
• List and discuss types of anemia
• Discuss disorders associated with the cardiovascular system (e.g., anemia, hemophilia, clotting disorders, leukemia)
• Blood pressure demonstration and discussion
• Textbook readings: pages 608-614, 619-622

Blood

• Connective tissue composed of:
  • Blood cells
  • Formed elements of blood
  • Plasma
  • Serum = plasma without clotting factors
• Blood volume:
  • Average adult: approximately 5 liters
  • Circulates in the body
  • Formation (hematopoiesis) takes place primarily in bone marrow

Red Blood Cells (RBCs) - Erythrocytes

• Produced in red bone marrow
• Mature RBCs don't contain nuclei, but contain hemoglobin, which carries oxygen from lungs to body cells.
• Lab tests: RBC count
  • Average: 4.0 - 6.5 million per cubic mm of blood
  • Used to determine anemia

RBC Formation

• Two million RBCs are produced every second

Composition of Blood

• Plasma: watery part of blood
• Formed elements: cells
  • Erythrocytes (red blood cells): carry oxygen and carbon dioxide
  • Leukocytes (white blood cells):
    • Granulocytes (contain granules):
      • Neutrophils: kill bacteria
      • Eosinophils: parasitic infections
      • Basophils: inflammation
    • Non-granulocytes (don't contain granules):
      • Lymphocytes:
        • T cells: in Thymus gland
        • B cells: become plasma cells producing antibodies
      • Monocytes: clean up debris/bacteria/dead cells
• Platelets (thrombocytes): help stop bleeding, clot formation

WBCs in the Blood

• White blood cells (leukocytes) fight infection
• Lab tests: WBC count
  • 5,000 to 11,000 per cubic mm of blood
  • Used to detect infection

Common Disorders - Anemia

• Abnormally low number of red blood cells
• Many causes
  • Decreased production of healthy red cells by bone marrow
  • Increased erythrocyte destruction (hemolysis)
  • Blood loss (heavy menstrual periods or internal bleeding)
  • Vitamin and mineral deficiencies
  • Abnormal hemoglobin or insufficient hemoglobin in RBCs
• Affects 3.5 million Americans

Common Disorders - Anemia (Specific Types)

• Iron-deficiency anemia: decreased iron levels decreasing hemoglobin production decreasing RBC oxygen transport
• Vitamin deficiency anemia: vitamin B12 is essential for hemoglobin production; pernicious anemia is b12 deficiency
• Hemolytic anemia: premature destruction of RBCs by antibodies
• Sickle cell anemia: caused by sickling (malforming) red blood cells leading to serious, life-threatening, inherited anemia and causes physical pain
• Aplastic anemia: unexplained failure of bone marrow to produce certain types of blood cells, bone marrow replaced with fat cells

Symptoms of Anemia

• Central: fatigue, dizziness, fainting
• Blood vessels: low blood pressure
• Heart: palpitations, rapid heart rate, chest pain, angina, heart attack
• Spleen: enlargement
• Skin: paleness, yellowing
• Eyes: yellowing
• Respiratory: shortness of breath
• Muscular: weakness
• Intestinal: changed stool color

Symptoms - Various Anemia (Specific Types)

• Sickle cell anemia: pain in abdomen, joints, bones, infections, and heart failure
• Aplastic anemia: bleeding in mucous membranes, infections, paleness, and dyspnea

Treatment - Anemia

• Treatment depends on type and cause of anemia
• Deficiencies: injections of vitamin B12, oral dietary supplements
• General care: blood transfusions, analgesics, antibiotics

Leukemia

• Cancer found in blood and bone marrow
• Caused by too many white blood cells
• WBCs don't allow body to fight disease and make red blood cells and platelets
• Malignant cancer of bone marrow and blood
• Uncontrolled growth of abnormal white blood cells (WBCs)
• Classified into acute or chronic leukemias
  • Lymphocytic leukemia: strikes lymphoid cells
  • Myeloid or myelogenous leukemia: strikes myeloid cells
• Symptoms include excessive bruising, fatigue, weakness, dyspnea (difficulty breathing), bleeding in mucous membranes, bone and joint pain, abdominal pain and bleeding, weight loss, enlargement of lymph nodes, spleen, liver, and frequent infections
• Treatments include chemotherapy, radiation therapy, and bone marrow transplantation

Coagulation and Clots

• Diseases associated with blood clots:
  • MI (Myocardial Infarction): heart attack
  • CVA (Cerebrovascular Accident): stroke
  • TIA (Transient Ischemic Attack): pre-stroke
  • PE (Pulmonary Embolism): clot in lungs
  • DVT (Deep Vein Thrombosis): clot in legs/calves

Stroke and Mini-Stroke

• Transient ischemic attacks (TIAs, or mini-strokes): temporary blockage of cerebral artery decreases blood flow to brain
• Stroke: complete blockage of cerebral artery, leading to brain cell death and permanent loss of certain functions

Signs of Stroke

• Sudden weakness (especially on one side of the body)
• Vision loss (especially in one eye)
• Unexplained dizziness, loss of balance, or coordination
• Loss of speech, trouble talking, or understanding language

Thrombophlebitis

• Blood clot causes inflammation in one or more veins, typically in lower extremities; deep vein thrombosis (DVT)
• Increases risk of serious health problems (e.g., PE)
• Caused by prolonged inactivity
• Decreases blood flow through veins; symptoms include redness, swelling, warmth, tenderness, dull ache or pain in affected area, and a red, hard, tender cord present under skin surface,

Deep Vein Thrombosis (DVT)

• Blood clot in a deep vein of the leg or pelvis potentially blocking the flow of blood
• A portion can break off and travel to heart, then lung to cause PE

Pulmonary Embolism (PE)

• Blood clot (from DVT) that travels to a lung, blocking vessel and disrupting blood supply to lung

Blood Types

• ABO blood typing system
• Rh (Rhesus) blood typing system, identifying the presence or absence of Rh antigens on RBCs, critical in blood transfusions to avoid transfusion reactions

ABO Blood Types (Antigen and Antibody)

• Type A: antigen A; antibody B
• Type B: antigen B; antibody A
• Type AB: antigens A and B; no antibodies
• Type O: no antigens; both antibodies A and B

Rh Factor

• Identifying the presence or absence of Rh antigens on RBCs

Transfusion Incompatibility

• Agglutination (clumping) of donor RBCs by recipient antibodies; leads to hemolysis (rupturing) of RBCs
• Resulting complications include jaundice, cardiac shock, and renal shutdown

Rh Incompatibility and Erythroblastosis Fetalis

• Rh incompatibility between mother and fetus during pregnancy, potential for hemolytic disease of the newborn (HDN)

Blood Pressure

• Measuring blood pressure, important vital sign for overall health
• Sphygmomanometer used to measure blood pressure
• Readings include systolic (top number) and diastolic (bottom number) values;
  • Normal: systolic lower than 120 mm Hg and diastolic lower than 80 mm Hg.
  • Prehypertension: systolic between 120 and 139 mm Hg or diastolic between 80 and 89 mm Hg
  • Hypertension/high blood pressure: readings above these values.

Hypertension (HTN) Risk Factors

• Genetic factors
• Obesity
• Inactivity
• Salt intake
• Stress
• Alcohol consumption
• Low K (potassium) and Ca (calcium)
• Smoking