Hemoglobin (Hb) Test

 



1. Objective:

The objective of the hemoglobin test was to measure the concentration of hemoglobin in the blood to assess oxygen-carrying capacity and screen for anemia or polycythemia.

2. Principle:

The test was based on converting hemoglobin into a stable form (e.g., cyanmethemoglobin or azide methemoglobin) and measuring its absorbance using a colorimeter or automated analyzer. The color intensity correlated with hemoglobin concentration.

3. Materials:

  • EDTA-anticoagulated blood sample
  • Hemoglobin reagent (e.g., Drabkin’s solution or automated kit)
  • Test tubes or cuvettes
  • Pipettes
  • Colorimeter or hematology analyzer
  • Gloves and lab safety items

4. Procedure (Microscopic/Spectrophotometric):

  1. Blood was collected using standard phlebotomy techniques into an EDTA tube.
  2. A fixed volume of blood was mixed with hemoglobin reagent.
  1. The mixture was allowed to react for a set time (usually 5–10 minutes).
  2. Absorbance was measured at 540 nm.
  3. Hemoglobin concentration was calculated using a calibration curve or by the machine.

5. Result:

  • Normal ranges:
    • Men: 13.8 – 17.2 g/dL
    • Women: 12.1 – 15.1 g/dL
    • Children: 11 – 13 g/dL
  • Low Hb: Indicates anemia
  • High Hb: Indicates dehydration or polycythemia

6. Uses:

  • Diagnose anemia and its severity
  • Monitor chronic disease (e.g., kidney disease)
  • Evaluate blood loss or hemolytic conditions
  • Pre-operative assessment
  • Monitor nutritional status

7. Consultation:

If abnormal, further tests were advised (e.g., complete blood count, iron studies, vitamin B12, folate). Physicians interpreted results in context of symptoms, medical history, and other lab findings.

 

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