Plasma Volume Calculator

How to Use the Calculator

1. Enter the Total Body Water (TBW) in liters. This can be estimated or measured based on individual characteristics.
2. Enter the Plasma Volume Fraction (PVF) as a percentage. This is the fraction of total body water that is in the plasma.
3. Click the "Calculate" button to compute the plasma volume.
4. The result will be displayed in liters.

Understanding the Formula

The plasma volume is calculated using the formula:

Plasma Volume (PV) = TBW × (PVF / 100)

This formula multiplies the total body water by the plasma volume fraction (expressed as a decimal) to determine the volume of plasma in the body.

Typical Values

The typical plasma volume fraction (PVF) in adults is approximately 5-6% (0.05-0.06). Using these values:

For a person with a total body water of 40 liters:

• With PVF = 5%: Plasma Volume = 40 × 0.05 = 2.0 Liters
• With PVF = 6%: Plasma Volume = 40 × 0.06 = 2.4 Liters

Applications

The Plasma Volume Calculator is useful in clinical settings for:

• Assessing fluid status in patients
• Calculating drug dosages that depend on plasma volume
• Evaluating hydration status