Page 6 of 13
PA13.2-4 | Welcome to Performing Common Haematological Tests: Hb, RBC/WBC, DLC
Learning Objectives
- Perform hemoglobin estimation using cyanmethemoglobin (gold standard) and Sahli's methods, explaining the principle and sources of error for each
- Carry out manual and automated RBC and WBC counts using the Neubauer hemocytometer, applying the correct diluting fluids, dilution ratios, and counting formulas
- Prepare a wedge peripheral blood smear, apply Leishman stain, and perform a 100-cell differential leukocyte count (DLC) using the systematic scanning approach
- Apply daily calibration, quality-control principles, and delta checks when using automated haematology analyzers
- Identify pre-analytical and analytical errors (clotted sample, storage artefacts, EDTA-platelet clumping) and take corrective action before reporting results
INSTRUCTIONS
Your EDTA tube from the phlebotomy session is now in the lab. The next 14 minutes convert that sample into the numbers that clinicians use every day: Hb, total counts, and a differential. Getting these right — or catching when they are wrong — is the core practical skill of this module. Work through each section step by step; the micro-quizzes test the calculations and troubleshooting logic you will use in your CP posting.
References
- Harsh Mohan — Textbook of Pathology, 8th ed., Chapter on Laboratory Haematology (textbook)
- Dacie & Lewis — Practical Haematology, 12th ed. (textbook)
- Mukherjee — Clinical Haematology, 3rd ed. (textbook)
- ICMR Standard Operating Procedures for Haematology Labs (2022) (guideline)
Version 2.0 | NMC CBUC 2024