neonatal_partial_exchange: Neonatal Partial Exchange Transfusion for Polycythemia

In cliot: Clinical Indices and Outcomes Tools

Neonatal Partial Exchange Transfusion for Polycythemia

Description

Calculates the volume of blood to be exchanged (removed and replaced with normal saline) to treat symptomatic neonatal polycythemia. The calculation determines the volume required to lower the central hematocrit to a safe target level.

Usage

neonatal_partial_exchange(weight_kg, current_hct, desired_hct = 55,
                          blood_volume_ml_kg = 80)

Arguments

weight_kg	Numeric. The infant's weight in kilograms.
current_hct	Numeric. The infant's current central hematocrit percentage (e.g., 70).
desired_hct	Numeric. The target hematocrit percentage. Defaults to 55% (common clinical target).
blood_volume_ml_kg	Numeric. Estimated total blood volume per kilogram. Defaults to 80 mL/kg (standard estimate for term infants). Range typically 80-90 mL/kg.

Details

The formula used is:

Volume_{exchange} = \frac{TBV \times (Hct_{current} - Hct_{desired})}{Hct_{current}}

Where TBV (Total Blood Volume) = Weight \times 80 mL/kg.

Value

A list containing:

Volume_to_Exchange_mL	The calculated volume of blood to exchange for normal saline.
Total_Blood_Volume_mL	The estimated total blood volume of the infant.

References

Wiswell TE, Cornish JD, Northam RS. Neonatal polycythemia: frequency of clinical manifestations and other associated findings. Pediatrics. 1986;78(1):26-30.

Examples

# Example 1: Symptomatic Polycythemia
# 3.5 kg infant, Hct 70%, Target 55%
# TBV = 3.5 * 80 = 280 mL
# Exchange = (280 * (70 - 55)) / 70 = 60 mL
neonatal_partial_exchange(3.5, 70, 55)

# Example 2: Higher TBV Estimate
# 4.0 kg infant, Hct 68%, Target 50%, TBV est 90 mL/kg
neonatal_partial_exchange(4.0, 68, 50, 90)

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