1. Anemias
Definition:
Anemia is defined as the decrease
in oxygen carrying capacity of the
blood either due to decrease number of
RBC’s or decrease Hb content.
O2 carriage
2. :Classification of anemias
Hemorrhagic
Hemolytic
A- According to the cause
Aplastic
Nutritional
B- According to size of RBC’s and Hb concentration
Normocytic
normochromic
Microcytic
hypochromic
Macrocytic
hyperchromic
3. A- According to the cause
Hemolytic anemias
a) Intracapsular causes
abnormalities in
the red cell membrane
e.g. herditary spherocytosis
abnormalities in Hb
e.g. G.6.P.deficiency
incompatible blood transfusion
b) Extracapsular causes
certain drugs
hypersplenism
4. A- According to the cause
Aplastic anemia
a) Certain drugs e.gchloramphenicol
b) Exposure to gamma ray radiation or excessive
X-ray treatment
c) Leukemia
.d) Certain chronic infections
fibrosis of B.M
5. A- According to the cause
Nutritional (deficiency) anemias
• Iron deficiency anemia
• Prenicious anemia due to Vit. B12 deficiency
• Macrocytic anemia due to folic acid deficiency
6. B- According to size of RBC’s
and Hb concentration
Normocytic
Normochromic
Microcytic
Macrocytic
hypochromic hyperchromic
Size of
normal
Decreased
RBC’s
HB
normal
Decreased
content
Causes Blood loss Iron
Hemolysis
Aplastic
Chronic
infections
deficiency
Thalassemi
a
Increased
Increased
Vit.12
deficiency
Folic acid
deficiency
7. Effects of anemia
viscosity
peripheral resistance
diastolic pressure and the venous return to the
heart.
Anemic hypoxia
peripheral vasodilatation
venous return to the heart
The cardiac output is thus increased and
workload of the heart is greatly increased
8. •
At rest the oxygen supply to
the tissues may not affected
because of the increased
cardiac output.
• however severe tissue
hypoxia results with exercise.