Download Hematology

Hematology
The Study of blood
• Average adult = 810 pints of blood
• Composition:
– PLASMA – liquid
portion of blood
without cellular
components
– Serum – plasma
after a blood clot is
formed
– Cellular elements
are red cells, white
cells and platelets
PLASMA
• Straw colored, contains –
– Water
– Blood proteins
– Plasma proteins
• FIBRONOGEN – necessary for
blood clotting, synthesized in
the liver
• ALBUMIN – from the liver, helps
maintain blood’s osmotic
pressure and volume
• PROTHROMBIN – a globulin
which helps blood coagulate.
Vitamin K necessary for
prothrombin synthesis.
Plasma
– Nutrients
– Electrolytes
– Hormones, vitamins, enzymes
– Metabolic waster products
Erythrocytes-Red Blood Cell
• Shape = biconcave discs
• RBC
• HEMOGLOBIN – gives red
color, heme is iron and
globin is protein.
• Function = transports
oxygen to tissues and
carbon dioxide away from
cells
• Normal – men =14-18 gm,
women = 12-16 gm
Function of Hemoglobin
• Red cells travel through the lungs
where
• O2 is carried to tissues and released
• CO2 picked up and carried back to
lungs for exchange
• Arterial blood – lots of oxygen = bright
red
• Venous blood – lots of CO2 = dark
crimson
ERYTHROPOIESIS
•
•
•
•
Manufacture of red blood cells
Occurs in bone marrow
Red cells live 120 days
Old cells broken down by the spleen
and liver
• HEMOLYSIS – rupture or bursting of
erythrocyte, can be from a blood
transfusion or disease.
White Blood Cells –
LEUKOCYTES
• Larger than erythrocytes
• 5 types
• Normal leukocyte count
= 3,200 – 9,800
• Types of White Cells
• Neutrophils
• Eosinophils
• Basophils
• Lymphocytes
• Monocytes
Leukocytes
• Basophils produce
HEPARIN – an
anticoagulant
• DIAPEDESIS –
when white cells
move through
capillary wall into
neighboring tissue.
• PHAGOCYTOSIS –
process when white
cells surround,
engulf, and digest
harmful bacteria.
Inflammation
• Body’s reaction to chemical or physical
trauma
• PATHOGENIC – disease producing
microorganisms can cause
inflammation
• Symptoms – redness, local heat,
swelling and pain
• Why? Bacterial toxins, increased blood
flow, collection of plasma in tissues
(edema)
• HISTAMINE increases the blood flow to
the injured area
• PUS produced – a combination of dead
tissue, dead and living bacteria, dead
leukocytes and plasma
• ABSCESS – pus-filled cavity below the
epidermis
• PYREXIA – increase in body
temperature by the hypothalamus – in
response to pathogenic invasion
Abscess
Inflammation
• LEUKOCYTOSIS –
increase in the
number of white
cells in response to
infection
• LEUKOPENIA –
decrease in number
of white cells due to
chemotherapy or
radiation
Thrombocytes (Platelets)
• Smallest of solid
components of blood
• Synthesized in red
marrow
• Not cells – fragments
of megakaryocytes
• Necessary for the
initiation of the blood
clotting process
Coagulation (Clotting)
• Cut or injury  platelets and injured
tissue release THROMBOPLASTIN 
act on PROTHROMBIN in plasma  +
Calcium ions converts to THROMBIN
 the thrombin acts as an enzyme and
changes FIBRINOGEN  FIBRIN
creating a mesh that traps red blood
cells, platelets and plasma creating a
blood clot.
• ANTICOAGULANTS – prevent blood
clotting
• HEPARIN = antiprothrombin
• PROTHROMBIN – dependent on
Vitamin K
Blood Facts
• There are about one billion red
blood cells in two to three
drops of blood. For every 600
red blood cells, there are about
40 platelets and one white cell.
Blood Types
• Four major types of
blood- A, B, AB and
O
• Inherited from
parents
• Determined by
presence or
absence of an
ANTIGEN on the
surface of the red
blood cell
• ANTIBODY – a protein in the plasma
that will inactivate a foreign substance
that enters the body.
– Someone with type A blood has b
antibodies
– Someone with type B blood has a
antibodies
– Someone with type AB blood has no
antibodies
– Someone with type O blood has a and b
antibodies
Blood Types
• UNIVERSAL
DONOR – O
• UNIVERSAL
RECIPIENT – AB
• Red cells also may
contain Rh factor
• If you have it, you’re
Rh +
• If you don’t, you’re
Rh –
RH Incompatibilties
Disorders of the Blood
• ANEMIA
• Deficiency in
number or % of red
cells
IRON-DEFICIENCY ANEMIA
• Usually in women, children and
adolescents
• Deficiency of iron in the diet causing
insufficient hemoglobin synthesis
• Treat with iron supplements and green,
leafy vegetables
APLASTIC ANEMIA
• Bone marrow does
not produce enough
red and white blood
cells
• Caused by drugs or
radiation therapy
SICKLE CELL ANEMIA
• Chronic blood disease
inherited from both
parents
• Causes the red cells to
form in abnormal sickle
shape
• Sickle cells break easily
and carry less oxygen
• Occurs primarily in
blacks
• Treatment – blood
transfusions
POLYCYTHEMIA
• Too many red blood
cells are formed
• May be a temporary
condition that
occurs at high
altitude
EMBOLISM
• Air, blood clot,
cancer cells, fat, etc.
that is carried by the
bloodstream until it
reaches an artery
too small for
passage
• Also known as a
“moving blood clot”
THROMBOSIS
• The formation of
a blood clot in a
blood vessel
• The blood clot is
a THROMBUS
HEMATOMA
• Localized clotted
mass of blood found
in an organ, tissue
or space.
• Caused by an injury
that can cause a
blood vessel to
rupture
HEMOPHILIA
• Hereditary
• Missing clotting
factor
• Blood clots slow or
abnormally
• Sex-linked –
transmitted
genetically from
mothers to sons
• Treat with missing
clotting factor, avoid
trauma
THROMBOCYTOPENIA
• Not enough
platelets
• Blood will not clot
properly
LEUKEMIA
• Malignant condition
• Overproduction of
immature white
blood cells
• Hinders synthesis of
red cells