therapeutic_plasmapheresis: Therapeutic Plasmapheresis (Plasma Exchange) Calculator

In cliot: Clinical Indices and Outcomes Tools

Therapeutic Plasmapheresis (Plasma Exchange) Calculator

Description

Calculates the estimated Total Blood Volume (TBV), Estimated Plasma Volume (EPV), and the total volume of plasma to be removed/exchanged based on patient weight, hematocrit, and the desired number of plasma volumes to exchange.

Usage

therapeutic_plasmapheresis(weight_kg, hematocrit_percent, exchange_volume_pv = 1.0)

Arguments

weight_kg	Numeric. Patient weight in kilograms.
hematocrit_percent	Numeric. Patient's hematocrit as a percentage (0-100).
exchange_volume_pv	Numeric. The target number of plasma volumes to exchange (e.g., 1.0, 1.2, 1.5). Defaults to 1.0.

Details

The calculations use the following standard estimations (Gilcher's rule of thumb):

TBV (mL) = Weight (kg) \times 70 mL/kg

EPV (mL) = TBV \times (1 - Hct)

Exchange Volume (mL) = EPV \times Target PV

Note: 70 mL/kg is a standard estimate for adults; actual blood volume may vary based on body composition and demographics.

Value

A list containing:

Total_Blood_Volume_mL	Estimated Total Blood Volume.
Estimated_Plasma_Volume_mL	Estimated total plasma volume of the patient.
Volume_to_Exchange_mL	The volume of plasma to be removed/exchanged to meet the target.

References

Kaplan AA. Therapeutic plasma exchange: A technical overview. J Clin Apher. 2013;28(1):3-10.

Examples

# Example 1: Standard 1.0 PV exchange
# 70kg patient, Hct 40%
# TBV = 4900, EPV = 4900 * 0.6 = 2940 mL
therapeutic_plasmapheresis(70, 40, 1.0)

# Example 2: 1.5 PV exchange for TTP
# 80kg patient, Hct 30%
# TBV = 5600, EPV = 5600 * 0.7 = 3920 mL
# Exchange = 3920 * 1.5 = 5880 mL
therapeutic_plasmapheresis(80, 30, 1.5)

cliot documentation built on Dec. 1, 2025, 1:06 a.m.