cliot (version 1.0.0)

fat_free_mass: Fat-Free Mass (Janmahasatian Equation)

Description

Calculates the Fat-Free Mass (FFM) of a patient using the Janmahasatian equation. This metric is often used for pharmacokinetic dosing of drugs with narrow therapeutic indices (e.g., digoxin, aminoglycosides) in obese patients, as it provides a more accurate estimate of metabolically active tissue than total body weight or ideal body weight.

Usage

fat_free_mass(weight_kg, height_cm, sex)

Value

A list containing:

Fat_Free_Mass_kg

The calculated Fat-Free Mass in kg.

BMI

The calculated Body Mass Index used in the equation.

Arguments

weight_kg

Numeric. Patient actual body weight in kilograms.

height_cm

Numeric. Patient height in centimeters.

sex

String. Patient sex ("Male" or "Female").

References

Janmahasatian S, Duffull SB, Ash S, Ward LC, Byrne NM, Green B. Quantification of lean bodyweight. Clin Pharmacokinet. 2005;44(10):1051-1065. doi:10.2165/00003088-200544100-00004

Examples

# Example 1: Male
# 80kg, 180cm
fat_free_mass(80, 180, "male")

# Example 2: Female
# 70kg, 165cm
fat_free_mass(70, 165, "female")