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Burns
In a major burn the first danger is the airway and the second is fluid loss; estimate the burned area (partial thickness and deeper only), calculate fluids by weight and percentage, and titrate the rate to urine output.
Why it matters in the exam
Burns questions almost always require a calculation: the percentage of body surface area by the "rule of nines" (in adults and children), then the fluid volume for the first 24 hours and what share of it is given during the 8 hours that follow the burn itself — not from arrival at hospital. Remember that a superficial burn (first degree, like sunburn) is not counted, and that the formula is only a starting point: the real target is urine output.
A second recurring topic is inhalation injury: a patient trapped in an enclosed space, with soot in the mouth, singed nasal hair, hoarseness or stridor, needs early intubation before oedema closes the airway. Candidates are also asked about carbon monoxide poisoning (saturation measured by a standard pulse oximeter looks normal), circumferential burns that need escharotomy, electrical burns (hidden muscle damage, myoglobinuria and arrhythmias) and the criteria for transfer to a burns unit.
Key points
- Burned area by the rule of nines; only partial thickness and deeper are counted.
- Fluids: 2 mL per kg per percent in adults (3 in children), half during the 8 hours that follow the burn itself.
- The target is urine output: 0.5 mL/kg/hour in adults, 1 in small children.
- Inhalation injury — early intubation; carbon monoxide — 100% oxygen.
- Circumferential full-thickness burn impairing perfusion or breathing — escharotomy.
Summary table
| Depth | Appearance | Pain | Healing |
|---|---|---|---|
| Superficial (first degree) | Redness, no blisters | Painful | Within about a week, no scar; not counted in the area calculation |
| Superficial partial thickness | Blisters, pink moist base that blanches | Very painful | Within 2–3 weeks, usually without a scar |
| Deep partial thickness | Pale or mottled base, slow capillary refill | Reduced sensation | Slow healing with a scar; usually excision and skin grafting |
| Full thickness | White, leathery or charred dry skin | Painless | Does not heal by itself; excision and skin grafting |
Free exam questions
מה היתרון במתן נוזלים?היפרטוניים לפצועים עם כוויות (the question as examined, in Hebrew)
- א. מורידים בצקת
- ב. מורידים זרימה לימפטית
- ג. מונעים היפרקלמיה
- ד. מעלים net fluid intake
A 58-year-old male presents at the trauma room after being rescued from a burning house. Fully conscious, speaking in a hoarse voice and there are signs of burns in the nasal area, air intake is even, BP 150/87, pulse 100, pupils are equal and reactive to light. What is the next step in case management?
- A. Inserting a tube
- B. Performing a whole-body CT scan
- C. Insertion of bilateral chest drains
- D. Inserting a feeding tube
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Sources
- ATLS Advanced Trauma Life Support, Student Course Manual (American College of Surgeons), 10th edition (2018) — Thermal Injuries
- ISBI Practice Guidelines for Burn Care, 2016 (part 2: 2018) — Initial assessment, fluid resuscitation and referral
- Sabiston Textbook of Surgery, 21st edition (2022) — Burns
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-02. The text may contain errors; when in doubt, check the source.