A Sahli hemoglobin meter (or haemometer) is a traditional, portable device for estimating blood hemoglobin (Hb) levels, widely used in resource-limited settings to diagnose anemia by converting hemoglobin to brown-colored acid hematin and visually matching its intensity against a standard color chart in a comparator. It's a simple, kit-based tool with a graduated tube, pipette, stirrer, and hydrochloric acid, providing quick, though less precise, results compared to automated methods, notes a study from the Journal of Evidence-Based Medicine and Healthcare.

How it Works (Sahli's Method)

• Dilution: 

  Distilled water is added drop-wise and stirred until the color matches the standard brown glass in the comparator.

• Reading: 

  The hemoglobin concentration is read directly from the graduations on the tube, often in grams/dL or percentage.

1. Blood Collection: 

   A specific amount of blood is drawn using a calibrated pipette.

2. Conversion: 

   The blood is mixed with N/10 Hydrochloric Acid (HCl) in the graduated tube, converting hemoglobin into dark brown acid hematin.

Key Components

• Comparator: A holder with two standard brown glass strips for color matching.

• Hemoglobin Tube: Graduated glass tube (e.g., 2-22g/dL).

• Pipette: Calibrated for blood (e.g., 20 microliters).

• Stirrer: Glass rod for mixing.

• Reagents: N/10 HCl and distilled water.