Basic Haematology & Haematological Techniques-I Notes
Subject Overview
The program's introduction to haematology — the composition of blood, formation of its cellular components (erythropoiesis, leucopoiesis, thrombopoiesis), collection and preservation of samples, and the definition, principle, procedure, normal values and clinical significance of the core haematology tests: haemoglobinometry, TLC, DLC, ESR, PCV/
Subject at a glance
3
Units
27
Topics
4
Credits
3
Infographics
Unit-wise Syllabus
3 units — open any unit for detailed topic-wise notes, diagrams and important exam questions
- Definition
- importance and equipment used in haematology
- laboratory organization and safety measures
- composition and function of blood and normal cellular components
- formation of cellular components — erythropoiesis
- leucopoiesis
- thrombopoiesis
Erythropoiesis
Red blood cells
Leucopoiesis
White blood cells
Thrombopoiesis
Platelets from megakaryocytes
Study guide
This unit introduces haematology: its importance and equipment, laboratory organisation and safety, composition and function of blood and normal cells and the formation of blood cells (erythropoiesis, leucopoiesis, thrombopoiesis). Learn where and how each blood cell type forms.
- Collection and preservation of blood samples
- principle
- procedure
- normal values
- clinical significance and sources of error for haemoglobinometry
- total leucocyte count (TLC)
- differential leucocyte count (DLC)
- erythrocyte sedimentation rate (ESR)
- packed cell volume/haematocrit
- red cell indices
- absolute eosinophil count
- reticulocyte count
- platelet count
Haemoglobin
Men 13–17, women 12–15 g/dL
Low in anaemia
TLC
4,000–11,000/µL
High in infection
ESR (Westergren)
Men 0–15, women 0–20 mm/hr
Raised in inflammation
Platelet count
1.5–4.5 lakh/µL
Low in dengue, ITP
PCV
Men 40–50%, women 36–46%
Low in anaemia
Study guide
You study blood sample collection and preservation, and the principle, procedure, normal values, clinical significance and sources of error of core tests: haemoglobin, TLC, DLC, ESR, PCV, red cell indices, absolute eosinophil count, reticulocyte count and platelet count. Memorise the normal ranges and what high and low values suggest.
- Types and methods of blood film preparation (thick and thin smear)
- Romanowsky staining principle
- composition
- reagent preparation and procedure — Giemsa
- Leishman
- Wright's
- Field's and JSB stains
- 1
Place a drop of blood near one end
- 2
Spreader at 30–45°
Push smoothly
- 3
Air dry
Feathered tail = good smear
- 4
Leishman stain
2 min: fixes the smear
- 5
Add buffered water
Dilute and stain about 8–10 min
- 6
Wash, dry and examine
Oil immersion
Study guide
You study thick and thin blood film preparation and Romanowsky staining (Giemsa, Leishman, Wright's, Field's and JSB). A good smear and stain make an accurate differential count possible, so practise both.
Why Basic Haematology & Haematological Techniques-I Matters
A complete blood count is the most commonly ordered laboratory test, and haematology skills are in demand in every hospital and diagnostic lab.
How to Prepare for Basic Haematology & Haematological Techniques-I
- Learn normal values and the clinical meaning of abnormal counts.
- Practise making and staining smears until they are consistently good.
- Understand the sources of error in each test.
Basic Haematology & Haematological Techniques-I: Frequently Asked Questions
What is a complete blood count?
A CBC measures haemoglobin, red cell, white cell and platelet counts and related indices to assess general health and detect disorders.
Why are blood smears stained?
Staining makes the different blood cells visible so that they can be identified and counted under the microscope.