HEMATOLOGY
Other anticoagulated micro collection tubes
Non-anticoagulated micro collection tubes
Sodium fluoride
Hematology from the Greek word “haima” meaning blood
and “logy” meaning study.
Hematology, the discipline that studies the development and
diseases of blood, is an essential medical science.
BLOOD FILM PREPARATION
1.
BLOOD
Total volume:
2.
(Ave. of 5 to 6L for male, 4to
5L for female)
3 LAYERS OF BUFFY COAT
3.
o Upper most: Platelets
o Middle layer:
Agranulocytes
o Lower layer:
Granulocytes, nRBC
Cover glass method
o Uses 2 cover glass smears
o Usually used for bone marrow samples
Wedge smear
o Uses 2 slides, 20/30-45-degree angle
o Most convenient and most commonly used
method, recommended by CLSI for WBC
differential counting
Spun smear
o Buffy coat smear
o Thick and thin smear for malarial parasites
GENERAL CHARACTERISTICS OF BLOOD
In vivo, blood is in fluid form; in vitro, it coagulates 5-10
minutes
Blood pH: 7.35-7.45 (average of 7.40)
•
•
Arterial (oxygenated) blood: Bright red
Venous (deoxygenated) blood: Dark Purplish Red
Note: In the pulmonary area the color is reverse. The color of
the blood in the pulmonary vein is bright red while the color of
the blood in the pulmonary artery is dark-purple red.
PLASMA
SERUM
Fluid portion of
anticoagulated blood
Slightly hazy appearance
Contains all coagulation
factors
Fluid portion of nonanticoagulated blood
Clear appearance
Lacks fibrinogen group
1.
ORDER OF DRAW (ETS and Syringe method)
Blood culture
Coagulation
Serum tubes
Green stopper
Lavender
stopper
Gray stopper
COUNTING METHODS OF CELLS
SPS
Sodium citrate
8-10x inversion
3-4x inversion
Heparin
EDTA
8-10x inversion
8-10x inversion
Sodium fluoride
8-10x inversion
ORDER OF DRAW (SKIN PUNCTURE)
Blood gases
Slides (unless made from EDTA)
2.
3.
Cross-sectional/crenellation
o Cells are counted side to side
Longitudinal
o Cells are counted in consecutive fields from
tail toward the head of the smear
Battlement/track pattern/back and forth serpentine
o Most preferred method of counting
HEMATOPOIESIS
Hematopoiesis is a continuous, regulated process of blood cell
production that includes cell renewal, proliferation,
differentiation, and maturation.
1.
2.
3.
Erythropoiesis
Leukopoiesis
Thrombopoiesis
HEPATIC PHASE
The hepatic phase begins at 5th to 7th week of gestation
Hematopoiesis during this phase occurs extra vascularly, with
the liver remaining as the major site hematopoiesis during the
second trimester of fetal life
Hemoglobin F is now the predominant hemoglobin, but
detectable levels of adult hemoglobin (Hb A) may be present
MEDULLARY/MYELOID PHASE
Prior to the 5th month of fetal development, hematopoiesis
begins in the bone marrow cavity
Sternum and other flat bones are the principal source of
production in adult
Production of Hb A and Hb A2
At birth, the BM is very cellular with mainly red marrow,
indicating very active blood cell production
Blood cell production, maturation, and death occur in organs
of the RES
RES includes Bm, spleen, liver, thymus, and lymph nodes
RES functions in hematopoiesis, phagocytosis, and immune
defense
PRIMARY LYMPHOID TISSUES (CENTRAL LYMPH
ORGAN)
•
Red marrow is gradually replaced by inactive yellow marrow
composed of fat. However, under physiologic stress, yellow
marrow may revert to active red marrow.
Site of adult hematopoietic
tissue
Primary site of adult
hematopoiesis
Secondary site of adult
hematopoiesis
Bone marrow, lymph
nodes, spleen, liver, and
thymus
Bone marrow
Liver and spleen
Thymus, bone marrow
SECONDARY LYMPHOID TISSUES (PERIPHERAL
LYMPHOID ORGAN)
Lymph nodes, spleen, GALT
STAGES OF HEMATOPOIETIC DEVELOPMENT
1.
2.
3.
Mesoblastic phase/yolk sac phase
Hepatic phase
Medullary/myeloid phase
Mesoblastic phase/yolk sac phase
Begins around 19th day of embryonic development after
fertilization
Formation of primitive erythroblast in the central cavity of the
yolk sac
Stages of primitive hematopoiesis
EMBRYOGENIC
HEMOGLOBINS
Gower I
Gower II
Portland
GLOBIN CHAIN
PRODUCTION
2 epsilon, 2 zeta
2 alpha, 2 epsilon
2 zeta, 2 gamma
EXTRAMEDULLARY HEMATOPOIESIS
Blood cell production outside of the bone marrow
Occurs mainly in the liver and spleen
Occurs when the bone marrow cannot meet body requirements
(ex. Aplastic anemia, hemolytic anemias)