Rule Of 9s Peds Calculator

Pediatric Rule of Nines Formula:

\[ TBSA (\%) = (18\% - age\ adjustment) \times head + 9\% \times (each\ arm) + (14\% + age\ adjustment) \times (each\ leg) + 18\% \times (anterior\ trunk + posterior\ trunk) \]

Age:

years

Head Proportion:

0-1

Each Arm Proportion:

0-1

Each Leg Proportion:

0-1

Anterior Trunk Proportion:

0-1

Posterior Trunk Proportion:

0-1

Total Body Surface Area (TBSA):

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1. What is the Pediatric Rule of Nines?

The Pediatric Rule of Nines is a modified version of the standard Rule of Nines used to estimate the total body surface area (TBSA) affected by burns in children. It accounts for the different body proportions in pediatric patients compared to adults.

2. How Does the Calculator Work?

The calculator uses the pediatric rule of nines formula:

\[ TBSA (\%) = (18\% - age\ adjustment) \times head + 9\% \times (each\ arm) + (14\% + age\ adjustment) \times (each\ leg) + 18\% \times (anterior\ trunk + posterior\ trunk) \]

Where:

\( age\ adjustment \) — 1% per year of age (up to 1 year)
\( head \) — Proportion of head affected (0-1)
\( each\ arm \) — Proportion of each arm affected (0-1)
\( each\ leg \) — Proportion of each leg affected (0-1)
\( anterior\ trunk \) — Proportion of anterior trunk affected (0-1)
\( posterior\ trunk \) — Proportion of posterior trunk affected (0-1)

Explanation: The formula adjusts for pediatric body proportions, where younger children have relatively larger heads and smaller legs compared to adults.

3. Importance of TBSA Calculation

Details: Accurate TBSA estimation is crucial for determining burn severity, guiding fluid resuscitation, planning treatment, and predicting outcomes in pediatric burn patients.

4. Using the Calculator

Tips: Enter the child's age in years and the proportion (0-1) of each body area affected by burns. All values must be valid (age 0-18, proportions 0-1).

5. Frequently Asked Questions (FAQ)

Q1: Why use a different rule for children?
A: Children have different body proportions than adults - larger heads and smaller legs relative to total body surface area.

Q2: How does age affect the calculation?
A: The adjustment accounts for changing body proportions as children grow. Younger children require more adjustment than older children.

Q3: What are the standard percentages for pediatric rule of nines?
A: Head: 18% (minus 1% per year), Each arm: 9%, Each leg: 14% (plus 1% per year), Trunk: 18% anterior + 18% posterior.

Q4: When should this calculator be used?
A: For initial assessment of pediatric burn patients to guide immediate treatment decisions and fluid resuscitation.

Q5: Are there limitations to this method?
A: This is an estimation tool. For precise measurements, especially in complex burn patterns, more detailed methods like Lund-Browder charts may be needed.