CV 5 Flashcards
Total Blood Volume
men
women
body weight
≈5 L in men,
≈4 L in women.
≈7% Body Weight (kg)
Blood Components (2)
- Cellular (Formed) Elements
2. Plasma
- Cellular (Formed) Elements (2)
Blood Cells
≈45% of whole blood
- Plasma (2)
H20 + Dissolved Substances
≈55% of of Whole Blood
Functions of blood (5)
Supplies nutrients and O2
Removes waste products and CO2.
Carries regulatory factors (hormones).
Defends against infection (immune function).
Hemostasis (keeping blood in blood vessels)
Plasma Contains (3)
92% H2O
7% Protein = Plasma Proteins
1% Dissolved substances
1% Dissolved substances (5)
Organic Molecules Ions Trace Elements Vitamins Dissolved Gasses
Plasma Proteins
Made by
liver
Plasma Proteins types (4)
- Albumins (main determinant ΠC)
- Globulins (Antibodies)
- Fibrinogen (Clotting Proteins)
- Others
Functions of Plasma Proteins (6)
Maintain ΠC Transport Proteins for lipids (steroids) Hormones Extracellular Enzymes Immunity Blood Clotting
Serum =
plasma – clotting proteins
Erythrocytes (RBC) –
Transport O2 and CO2
Leukocytes (WBC) –
Body Defense
Thrombocytes (Platelets) -
Hemostasis
Hematocrit
Percentage of total blood
volume occupied by blood
cells (RBCs)
1⁰ determinant of blood
viscosity
hemocrit
Normal hemocrit
– Women
– Men
38-46%
42-54%
An increase in hematocrit
will __ resistance and __
flow rate; it will also __ the
risk of turbulent flow.
increase
decrease
decrease
Hematopoiesis/Hemopoiesis (2)
Blood Cell production
Red Bone Marrow (Spongy bone)
All formed elements
(myeloid and
lymphoid) produced
from a common
“Pluripotent
Hematopoietic Stem
Cell”
Production of specific blood components dependent on which control factors are present: 1. Erythrocytes – 2. Leukocytes – 3. Thrombocytes -
- Erythrocytes – Erythropoietin
- Leukocytes – CSFs and ILs
(complex process) - Thrombocytes -
Thrombopoietin
Most Abundant Blood Cell
erythrocytes (5x106/μl whole blood)
Hematocrit =
%RBC in whole blood
40-54% Males
37-47% Females
RBC Function:
Transport O2 and CO2 between tissues and
lungs
RBC Cell Anatomy (4)
Biconcave disk in shape with a flexible membrane.
No nucleus or organelles (including no mitochondria)
No DNA
No Centrioles
Biconcave disk in shape with a flexible membrane. (2)
Creates Large surface area which favors simple diffusion.
Easily slip through Capillaries
Enzymes (2)
Glycolytic enzymes (glycolysis)
Carbonic anhydrase
Hemoglobin (2)
≈2x108/RBC
Binds oxygen and carbon dioxide
RBC lifespan
Short life span (about 120
days): ~1% lost/day.
RBC are rynthesized in red bone
marrow by the process called
erythropoiesis
RBC are filtered by the (2)
spleen
liver
Erythropoietin (kidney
hormone) triggers
differentiation of stem cells to
erythrocytes.
Reticulocytes (5)
Young Erythrocytes Contain some ribosomes Lose after 1 day 1% Circulating RBC Levels increase during periods of rapid RBC production
Erythrocyte Production Requires: (3)
Iron
Folic acid
Vitamin B12
Iron (4)
Component of hemoglobin (heme portion)
Normal hemoglobin content of blood
- Men: 13–18 gram / dL
- Women: 12–16 gram / dL
Folic acid (1)
Necessary for DNA replication, and therefore cell division
Vitamin B12 (2)
Necessary for DNA replication, and therefore cell division
Pernicious Anemia
Life Cycle of RBC
120 days
Normally RBC Production =
RBC
Destruction
(2) removes old erythrocytes
Spleen and Liver
Iron is
recycled
Liver metabolizes
Hb (Bile pigments – Bilirubin/Biliverdin)
Bile Pigments secreted along with bile into —. Lost from body via —
small intestine
feces
Iron deficiency
Hb deficiency
Hemochromatosis (2)
Too much iron Damages Liver, Heart, Pituitary Gland, Pancreas and Joints
secreted along with bile in Small Intestine (2)
Bilirubin/Biliverdin
Patients with chronic renal failure have too little
erythropoietin and require administration of
synthetic forms to maintain normal RBC counts.
Athletes who abuse this synthetic form (to increase
stamina) can die from
polycythemia
(increased [RBC]) which increases viscosity of blood increase R, decrease Blood Flow (F=ΔP/R) and results in clotting, stroke and heart failure.
Testosterone also enhances RBC production by
ncreasing EPO production (hence men have higher
hematocrit than women).
Anemia
Decrease in the oxygen-carrying capacity of blood: ↓# RBC and/or
↓[hemoglobin].
Dietary anemia (2)
– Iron: iron-deficiency anemia
– Vitamin B12: pernicious anemia
Hemorrhagic anemia (1)
– Bleeding
Hemolytic anemia (2)
– Malaria
– Sickle cell anemia
Aplastic anemia (1)
– Bone marrow defect
Renal anemia (1)
– Kidney disease
Polycythemia
Hct >
60%
Polycythemia vera (3)
– Genetic condition
– Over produce RBCs
– At risk for clotting
Secondary polycythemia (2)
– Due to hypoxia/ high altitude
– Heart failure
RBCs express numerous membrane
glycoproteins and glycolipids that serve as
antigens
Antigens (also called agglutinogens) are
proteins capable of inducing an
immune
response
Most antigens on RBC are
relatively weak
Blood Typing is based on 3 antigens found on the RBC membrane:
A, & B and Rh (D)
Presence or absence of A and B antigens determines
A, B, AB, or O blood type (Incomplete dominance)
Presence of absence of Rh antigen determines whether
Rh-positive or Rh-negative (Mendelian genetics)
Unlike most immune reactions,
a person already has
antibodies/agglutinins (IgMs) to
the
A/B antigens not on their
RBCs
Unlike most immune reactions, a person already has antibodies/agglutinins (IgMs) to the A/B antigens not on their RBCs. (2)
– These are in the plasma prior to any exposure. Appear 2-8 months after birth. • Introduced to the immune system through food and bacteria
Maximum titer is at – years, then declines with age
10
So what happens if inappropriate A-B-O blood is transfused?
if a person receives RBCs with
antigens that they have
agglutinins/antibodies against, the
RBCs will —
agglutinate
Antigens have multiple binding sites
as do antibodies, so multiple RBCs
clump together
Agglutination causes
obstruction of small blood vessels
Hours to days later, hemolysis occurs (2)
- Due to extreme distortion of RBCs and action of phagocytic WBCs
- It is possible to have acute hemolysis, but it is unlikely
The pathologic effects of agglutination can be (2)
extreme and fatal (systemic
inflammatory response, kidney failure,
intravascular coagulopathy, etc.)
When blood is transfused, it is not usually whole blood, but packed
RBCs. So the only reaction to worry about is between the
recipient’s plasma and the donor’s RBCs.
Which type of blood is the universal donor?
Which type of blood is the universal Recipient?