Lecture Flashcards
What is the main function of the circulatory system and what other systems do they include?
Transportation
It includes the cardiovascular system & lymphatic system
What is Red Blood Cells
Erythrocytes
What is White Blood Cells
Leukocytes
What kind of tissue is blood?
Connective tissue
What is Plasma?
Plasma is straw-colored, clear liquid that is 90 % water and substances like:
1. plasma proteins
a. albumin – maintains blood volume (“thickens” blood)
b. globulin – component of antibody production
c. fibrinogen and prothrombin - proteins necessary for blood clotting
2. nutrients
3. hormones
4. salts and minerals (sodium, potassium, calcium, magnesium)
5. oxygen
6. waste products of metabolism
Blood Amount vs. Plasma Volume
Blood is about 7-9% of the total body
weight. On the average, most adults have around 4-6 liters of blood.
Plasma volume is a little more than half of the total blood volume.
What is serum & what does it contain?
Serum is plasma minus the proteins in-charge of blood clotting. Serum is rich in antibodies.
FORMED ELEMENTS
Normal Average Counts among Adults:
1. Red Blood Cells (RBCs) Erythrocytes 4.2-6.2 M/mm3*
2. White Blood Cells (WBCs) Leukocytes 5,000 -10,000/mm3
3. Platelets – Thrombocytes 140,000 –
340,000/mm3
What is HEMATOPOIESIS and where does it occur?
The formation of blood cells occurs in myeloid tissue and in lymphatic tissue.
Where is Myeloid tissue found and what does it produce during hematopoiesis?
Myeloid tissue (red bone marrow) produces erythrocytes, platelets and white blood cells. In the adult, myeloid tissue is found mainly in the sternum, ribs and coxal bones (hip bones).
Except for the lymphocytes, the formed elements mature in the bone marrow before they are released to the peripheral circulation.
Where does Lymphocytes mature?
Lymphocytes mature in lymphoid tissue located mainly in the lymph nodes, thymus and spleen.
Life span of Blood Cells
Red Blood Cells 120 Days
Platelets 8-10 Days
White Blood Cells:
Granulocytes few Days
Non-granulocytes 180 Days
hemoglobin
. the protein (gives red color) that alternately binds with oxygen (oxyhemoglobin) for distribution to body tissues and with carbon dioxide
(carbamino-hemoglobin) for elimination
.Normal Average Hemoglobin Count: 13- 15 gm/dl
What is the major
component of
hemoglobin
Iron
Hematocrit
– the amount of RBCs in a volume of blood expressed in percentage
- Normal Average Hematocrit – 45%
Hematocrit Test
- blood in test tube is “spun down” in the centrifuge and blood forms layers in the tube:
plasma – top layer
buffy coat (WBCs and platelets) – middle layer
RBCs – bottom layer
Reticulocytes
– immature red blood cells
- Normal Reticulocyte Count 0.5-1.5%
- increase in reticulocyte count occurs when there is blood loss, hemolysis, or among individuals residing in high altitudes
Erythropoietin
– a hormonal substance produced primarily by the kidneys that enhances
erythropoiesis (bone marrow production of red blood cells)
erythropoiesis
bone marrow production of red blood cells
Anemia
– deficient number of red blood cells and/or deficient amount of hemoglobin in blood
- leads to inability of the blood to carry sufficient oxygen
Polycythemia
– excessive number of red blood cells
Types of WHITE BLOOD CELLS (WBC) - Leukocytes
Granulocytes - WBCs with granules in the cytoplasm
. Eosinophils
. Basophils
. Neutrophils
Agranulocytes/Non-granulocyte
. Monocytes
. Lymphocytes
-B-lymphocytes- produce antibodies
-T-lymphocytes – directly attack viruses and cancer cells
Eosinophils
– red granules in the cytoplasm
- active against parasites
- increase in the presence of allergic reactions
Basophils
- blue granules in the cytoplasm
- secrete histamine, heparin
Neutrophils
- with granules that are neither red or blue
- active phagocytes
Monocytes
- phagocytes and macrophages, largest WBCs
Lymphocytes
B-lymphocytes – produce antibodies
T-lymphocytes – directly attack viruses and cancer cells
Normal WBC count (adults):
5,000 -10,000/mm3
WBC differential count
shows the proportion of each type of white blood cell in the blood.
The normal differential count among adults is as follows:
Neutrophils: 60%
Lymphocytes: 30 %
Monocytes: 6 %
Eosinophils: 3 %
Basophils: 1 %
Abnormal WBC Counts
. Leukopenia
. Leukocytosis
. Leukemia
Leukopenia
– abnormally low WBC count , usually
below 5,000/mm3
Example: Immune Deficiency Diseases (HIV-AIDS)
Leukocytosis
– abnormally high WBC count, usually
above 10,000/mm3
Example: Bacterial infections
Leukemia
– white blood cell malignancy characterized
by massive leukocytosis
PLATELETS -THROMBOCYTES
. Platelets are not cells. They are cytoplasmic fragments of a big cell found in the bone marrow, the megakaryocyte.
. Life span of platelets: from 8 – 10 days
. Normal platelet count 140,000 – 340,000/mm3
Main function: blood clotting or coagulation
Thrombocytosis
– abnormally high platelet count
Thrombocytopenia
– abnormally low platelet count
Clotting Mechanism
- platelets become sticky at the site of tissue damage forming a soft, temporary platelet plug
- prothrombin activator is formed by clotting proteins and, together with calcium converts prothrombin to
thrombin thrombin converts fibrinogen to fibrin (the blood clot) which is a tangle of fine threads where RBCs and platelets are trapped
Thrombosis
– abnormal formation of a blood clot (thrombus) within an unbroken blood vessel
Embolism
– when part or whole of a thrombus is dislodged and circulates through the bloodstream
Complete Blood Count - A frequently requested laboratory test to determine the general health status of a patient
- Includes the following:
Red Blood Cell Count
Hemoglobin
Hematocrit
Reticulocyte count
White Blood Cell Count
WBC differential Count
Platelet Count
Blood Types – ABO and Rh
The letters (ABO) stand for a type of protein (called antigens) in the cell membrane of the red blood cells which have been there since birth.
In the plasma, antibodies exist against certain blood
types as follows:
Blood Type: A - Antigen: A - Antibody: anti-B
Blood Type: B - Antigen: B - Antibody: anti-A
Blood Type: AB - Antigen: AB - Antibody: None
Blood Type: O - Antigen: None - Antibody: anti-B and anti-A
Blood Transfusion
requires blood compatibility. When the donor blood type is incompatible with that of the recipient, blood clumping (agglutination) will occur. This will result in massive rupture (hemolysis) of RBCs which can be life threatening.
Blood clumping occurs when the receiver of a blood transfusion has antibodies against the donor blood cells.
Cross Matching
. The test of compatibility between the blood types of the donor and recipient
. The serum of each is allowed to react with the red blood cells of the other to determine the absence of agglutination
Rh Blood Groups
Rh-positive (Rh+) - Rh factor antigen present
Rh-negative(Rh-) - no Rh factor antigen BUT will form anti-Rh+ antibodies if exposed to Rh-positive blood
Erythroblastosis Fetalis
– disease of Rh-positive baby born to Rh-negative mother causing agglutination of baby’s blood hemolysis (abnormal breakdown of RBC) life threatening severe anemia and heart failure
AB+ is the universal recipient and O- is the universal donor
(Blood type AB does not have antibodies against any blood type. Rh positive recipients will not form antibodies against Rh negative donors. On the other hand, blood types A, B and AB do not have anti-O antibodies. Rh negative recipients can form antibodies against Rh positive donors leading to sensitization of the recipient.)
Rhogam
– trade name of a protein antibody that prevents the mother from destroying Rh positive red blood cells
Coagulation Studies
- Laboratory studies done to determine the effectiveness of the body’s ability to perform the process of blood coagulation Oftentimes performed prior to surgery to detect if
there is likely to be a problem of bleeding or clotting during or subsequent to a surgery - Likewise performed during the monitoring of a patient on anti-coagulant therapy or in patients with
suspected liver problem
Coagulation Studies Value
- Prothrombin Time (PT) 10 - 12 seconds
- Partial Thromboplastin Time (PTT) 30 - 45 seconds
- International Normalized Ratio (INR) - ensures consistency of PT test 1-2
results from across different
laboratories
Arterial Blood Gas Determination (ABG)
– test to measure the levels of oxygen and carbon dioxide in the blood extracted from an artery
- likewise measures the level of blood acidity (pH)
Serologic Tests
- tests carried out to detect the presence of antibodies or antibody-like substances in serum that appear specifically in association with certain diseases
Anemia
Inability of blood to carry sufficient oxygen to body cells
Caused either by decreased in red blood cells and/or a deficiency of hemoglobin leading to easy
fatigability, poor concentration, dizziness
Factors causing decreased red blood cell count:
- hemorrhage
- aplastic anemia
- pernicious anemia
hemorrhage
– excessive bleeding leading to loss
of RBCs
aplastic anemia
– no bone marrow production of RBCs
pernicious anemia
– deficient production of RBCs due to inadequate amounts of vitamin B12 which in turn is caused by absence of intrinsic factor in the stomach
Causes of decreased hemoglobin:
- Iron-deficiency
- Sickle cell anemia
- Polycythemia
- Bone Marrow Suppression
- Neoplastic Blood Diseases
5.1 Leukemia
5.2 Lymphoma - Hemophilia
- HIV-AIDS(Human Immunodeficiency Virus)
Iron-deficiency
– oftentimes due to nutritional lack
of iron which is the main mineral needed for hemoglobin production
Sickle cell anemia
– a hereditary and sometimes
fatal disease due to production of RBCs with less soluble form of hemoglobin (HbS)
- HbS forms solid crystals distorting the shape of the RBCs leading to hemolysis and subsequent anemia
Polycythemia
- excessive production of red blood cells leading to increased blood viscosity and greater risk for stroke or heart attack
Bone Marrow Suppression
– a complication of chemotherapy wherein the bone marrow undergoes short-term destruction leading to very low production of the formed elements
Neoplastic Blood Diseases
Leukemia – a malignancy of the bone marrow characterized by massive production of leukocytes
Lymphoma – malignancy of the lymphoid tissues cause by abnormal production of lymphocytes
Hemophilia
– an inherited bleeding disorder caused
by lack of specific coagulation protein
HIV-AIDS(Human Immunodeficiency Virus
Autoimmune Deficiency Syndrome) – a viral infection that severely damages the immune system of the affected individual leading to susceptibility to infectious diseases that can be fatal
