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Burn Surface Area Calculator

Rule of Nines Formula:

%TBSA = (Head 9% + Each arm 9% + Each leg 18% + Front torso 18% + Back torso 18% + Genitals 1%)

% (max 9%)
% (max 9%)
% (max 9%)
% (max 18%)
% (max 18%)
% (max 18%)
% (max 18%)
% (max 1%)

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1. What is the Rule of Nines?

Definition: The Rule of Nines is a method used to estimate the total body surface area (TBSA) affected by burns.

Purpose: It helps medical professionals quickly assess burn severity and determine fluid resuscitation needs.

2. How Does the Calculator Work?

The calculator uses the standard percentages:

%TBSA = (Head 9% + Each arm 9% + Each leg 18% + Front torso 18% + Back torso 18% + Genitals 1%)

Explanation: Each body region is assigned a percentage of total body surface area based on anatomical proportions.

3. Importance of Burn Surface Area Calculation

Details: Accurate TBSA estimation is critical for determining:

4. Using the Calculator

Tips: Enter the percentage burned for each body region. The calculator automatically caps values at their anatomical maximums.

5. Frequently Asked Questions (FAQ)

Q1: Why is the Rule of Nines important?
A: It provides a quick, standardized method for burn assessment in emergency situations.

Q2: Are there different versions for adults and children?
A: Yes, children have proportionally larger heads (up to 18% for infants) and smaller legs.

Q3: What about burns on hands or feet?
A: The palm of the patient's hand (including fingers) represents about 1% of TBSA and can be used for small burns.

Q4: When is a burn considered major?
A: Typically when >20% TBSA in adults or >10% in children, or when involving critical areas.

Q5: How accurate is the Rule of Nines?
A: It provides a good initial estimate but should be supplemented with more precise methods when possible.

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