1. What is the Bedside Schwartz Equation?

The Bedside Schwartz equation is a simplified formula used to estimate glomerular filtration rate (GFR) in children. It was developed by the National Kidney Foundation (NKF) as a practical tool for pediatric renal function assessment using height and serum creatinine measurements.

2. How Does the Calculator Work?

The calculator uses the Bedside Schwartz equation:

Where:

• \( eGFR \) — Estimated glomerular filtration rate (mL/min/1.73m²)
• \( Height \) — Patient's height in centimeters (cm)
• \( Scr \) — Serum creatinine in milligrams per deciliter (mg/dL)
• \( 0.413 \) — Constant coefficient derived from pediatric population studies

Explanation: This equation simplifies the original Schwartz formula for easier clinical use while maintaining reasonable accuracy for pediatric patients.

3. Importance of Pediatric eGFR Calculation

Details: Accurate GFR estimation in children is essential for detecting kidney dysfunction early, monitoring chronic kidney disease progression, and adjusting medication dosages appropriately for pediatric patients.

4. Using the Calculator

Tips: Enter height in centimeters and serum creatinine in mg/dL. Ensure both values are positive numbers. Height should be measured accurately using a stadiometer for reliable results.

5. Frequently Asked Questions (FAQ)

Q1: What age range is this calculator appropriate for?
A: The Bedside Schwartz equation is validated for children and adolescents aged 1-18 years.

Q2: Why is height used in pediatric GFR calculations?
A: Height serves as a proxy for muscle mass in children, which correlates with creatinine production and thus provides a more accurate GFR estimation.

Q3: What are normal eGFR values for children?
A: Normal pediatric eGFR values vary by age but generally range from 90-140 mL/min/1.73m², with higher values in younger children.

Q4: Are there limitations to this equation?
A: This equation may be less accurate in children with extreme body habitus, malnutrition, or muscle wasting conditions.

Q5: When should this calculator not be used?
A: Avoid using for infants under 1 year, patients with rapidly changing kidney function, or those with amputations or significant edema.