Hemolysis Index Calculator

Welcome to the Hemolysis Index Calculator! This tool helps laboratories and researchers quickly determine the level of hemolysis in a blood sample. Hemolysis, which refers to the breakdown of red blood cells, can interfere with many biochemical tests, so measuring its extent is crucial for reliable results.

With just a few absorbance readings, this calculator provides a fast estimate of hemolysis index values, making it easier for clinicians and scientists to assess sample quality. You can begin calculating right away, or keep reading to explore the formulas, step-by-step examples, and explanations of the parameters involved.

Understanding the Formula

The calculator uses well-established formulas applied in clinical laboratories.

1. Simplified Two-Wavelength Formula
Corrected Absorbance = A_primary - A_secondary
Hemolysis Index (mg/dL) = Corrected Absorbance × K

• A_primary: Absorbance at the main wavelength for hemoglobin, usually 570 nm.
• A_secondary: Absorbance at a background wavelength (e.g., 600 nm) to correct for turbidity.
• K: A calibration constant that converts absorbance into hemoglobin concentration.

This method is quick, straightforward, and ideal for routine automated analyzers.

2. Harboe’s Formula (Three-Wavelength Method)
Hemoglobin Concentration (mg/L) = (2 × A_415 - A_380 - A_450) × 167.2

• A_415: Absorbance where oxyhemoglobin peaks.
• A_380 and A_450: Absorbance values used to correct for bilirubin and other interferences.
• 167.2: A conversion factor derived from hemoglobin’s molecular properties.

This formula is more precise and often used when accuracy is essential.

Parameters Explained

Here’s a closer look at each input:

• A_primary (570 nm): Detects hemoglobin concentration in the sample.
• A_secondary (600 nm): Helps adjust for non-hemoglobin background noise.
• K (Calibration Constant): A lab-specific factor provided by instrument calibration.
• A_415: Identifies the hemoglobin peak absorbance.
• A_380 & A_450: Correct for substances like bilirubin that could distort readings.
• 167.2: A fixed multiplier ensuring results are expressed in mg/L.

These values come directly from spectrophotometer readings, so accuracy in measurement is key.

How to Use the Hemolysis Index Calculator — Step-by-Step Example

Let’s try an example using the two-wavelength method:

1. Suppose your spectrophotometer shows:
   A_primary = 0.420, A_secondary = 0.100, K = 120.
2. Corrected Absorbance = 0.420 - 0.100 = 0.320
3. Hemolysis Index = 0.320 × 120 = 38.4 mg/dL

This means the sample has a hemolysis index of 38.4 mg/dL, which may indicate moderate hemolysis. Depending on your laboratory’s cutoff values, this sample might be flagged as unsuitable for certain tests.

Additional Information

Here’s a quick reference table for typical hemolysis index values:

These ranges can vary depending on the laboratory or analyzer used.

FAQs