cliot (version 1.0.0)

sodium_correction_rate: Sodium Correction Rate in Hyponatremia/Hypernatremia (Adrogue-Madias)

Description

Calculates the infusion rate of a selected fluid required to correct serum sodium to a target level over a specified time. Uses the Adrogue-Madias formula to estimate the change in serum sodium per liter of infusate.

Usage

sodium_correction_rate(current_sodium, target_sodium, time_hours,
                       fluid_sodium, weight_kg, percent_body_water = 0.5)

Value

A list containing:

Infusion_Rate_mL_hr

The calculated infusion rate in mL/hr.

Total_Volume_L

Total volume required to reach target.

Change_In_Serum_Na_per_L_Infusate

Estimated change in serum Na for every 1L infused.

Arguments

current_sodium

Numeric. Current serum sodium level (mEq/L).

target_sodium

Numeric. Desired target serum sodium level (mEq/L).

time_hours

Numeric. Duration over which to achieve the target (hours).

fluid_sodium

Numeric. Sodium content of the infusate (mEq/L). (e.g., 3% NaCl = 513, 0.9% NaCl = 154, D5W = 0).

weight_kg

Numeric. Patient weight in kilograms.

percent_body_water

Numeric. Fraction of total body water (e.g., 0.6 for men, 0.5 for women/elderly men, 0.45 for elderly women). Defaults to 0.5.

Details

The formula for the change in serum Na per liter of fluid is: $$\Delta Na = \frac{Fluid Na - Serum Na}{TBW + 1}$$ The volume required is: $$Volume (L) = \frac{Target Na - Current Na}{\Delta Na}$$

References

Adrogue HJ, Madias NE. Hyponatremia. N Engl J Med. 2000;342(21):1581-1589. doi:10.1056/NEJM200005253422107

Examples

# Example 1: Hyponatremia correction
# Na 115 -> 120 in 24h, using 3% Saline (513 mEq/L), 70kg Male (0.6 TBW)
sodium_correction_rate(115, 120, 24, 513, 70, 0.6)

# Example 2: Hypernatremia correction
# Na 155 -> 150 in 24h, using D5W (0 mEq/L), 60kg Elderly Woman (0.45 TBW)
sodium_correction_rate(155, 150, 24, 0, 60, 0.45)