1. What is a Potassium Deficit Calculator?

Definition: This calculator estimates the potassium deficit in adults based on current and target potassium levels, and distribution volume.

Purpose: It helps medical professionals determine potassium replacement needs for patients with hypokalemia.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( D \) — Potassium deficit (mmol)
• \( K_t \) — Target potassium level (mmol/L)
• \( K_c \) — Current potassium level (mmol/L)
• \( V \) — Distribution volume (L)

Explanation: The difference between target and current potassium levels is multiplied by the distribution volume to estimate total deficit.

3. Importance of Potassium Deficit Calculation

Details: Accurate potassium deficit estimation ensures proper electrolyte replacement, prevents overcorrection, and maintains cardiac stability.

4. Using the Calculator

Tips: Enter target potassium (default 4.0 mmol/L), current potassium level, and distribution volume (default 40L for adults). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's a typical target potassium level?
A: 4.0 mmol/L is standard, but may be adjusted based on clinical context (e.g., cardiac patients).

Q2: How is distribution volume determined?
A: 40L is standard for adults (60% body weight in kg for total body water, with potassium being 98% intracellular).

Q3: When would I adjust the distribution volume?
A: For patients with abnormal fluid status (edema, dehydration) or extreme body weights.

Q4: How should the deficit be replaced?
A: Typically 10-20 mmol/hr IV (max 40 mmol/hr with cardiac monitoring) or oral replacement for stable patients.

Q5: Does this account for ongoing losses?
A: No, additional replacement may be needed for continued potassium losses (diuresis, diarrhea).