Surgery chapters
Principles of treating burns, electrical and chemical burns
First aid and hospital care of burns, escharotomy, dressings and topical agents, early excision and grafting, nutrition, infection and scar care, and the special features of electrical and chemical burns.
- Treat a burn like any trauma: stop the burning, cool with running water (at least 10 minutes, up to about 1 hour after injury), then ABCDE plus fluids; give oxygen, analgesia (IV opioids, not IM) and tetanus cover.
- Circumferential full-thickness burns need escharotomy; deep dermal and full-thickness burns need early excision and split-skin grafting; superficial burns heal with simple dressings in about 2 weeks.
- Electrical burns hide deep muscle damage (myoglobinuria, arrhythmia, compartment syndrome); chemical burns need copious water lavage (alkalis are worse than acids; hydrofluoric acid needs calcium gluconate).
On this page
Overview
Burn care has three phases: first aid and resuscitation, wound care and closure, and rehabilitation with scar management. The principles are the same for all burns, but electrical and chemical burns have extra dangers that are easily missed. Fluid calculation is covered in the burn pathophysiology chapter; this chapter covers the rest of the treatment.
Prehospital first aid
- Rescuer safety first: turn off electricity, beware of fire and chemicals.
- Stop the burning: "stop, drop and roll"; remove hot or soaked clothing and jewellery.
- Cool the burn with cool running water for at least 10 minutes. It relieves pain and reduces tissue damage, and still helps up to about 1 hour after the burn. Do not use ice.
- Keep the patient warm: cool the burn, not the patient. ATLS warns against cold water on large burns (over 10% TBSA) because of hypothermia.
- ABC check and look for other injuries (explosions, falls, escaping from fire).
- Oxygen for anyone burned in an enclosed space.
- Cover with cling film or a clean sheet; elevate burned limbs and sit up a patient with a face burn.
Do not apply toothpaste, ghee, oil or ice to a burn. They add contamination or cold injury and delay proper cooling.
Hospital care: primary survey and resuscitation
Manage like any trauma patient:
| Step | Key actions |
|---|---|
| A Airway (with C-spine care) | Look for airway burn signs; early intubation if suspected |
| B Breathing | 100% oxygen; measure carboxyhaemoglobin; chest escharotomy if eschar restricts breathing |
| C Circulation | Two large-bore IV lines (through burned skin if necessary); start warmed Ringer's lactate; urinary catheter |
| D Disability | GCS; confusion may mean hypoxia or CO poisoning |
| E Exposure | Full exposure, estimate % TBSA and depth, keep warm |
| F Fluids | Calculate with a formula, titrate to urine output |
Secondary survey and adjuncts
- History: time, mechanism, enclosed space, chemicals, voltage, first aid given; AMPLE history.
- Bloods: FBC, group and crossmatch, electrolytes, glucose, arterial gas with HbCO, pregnancy test; ECG for electrical injury.
- Nasogastric tube for large burns (ATLS: more than 20% TBSA) or vomiting.
- Analgesia: small burns, paracetamol and NSAIDs; large burns, IV opioids in small frequent doses. Avoid IM injections in major burns because absorption is unpredictable.
- Tetanus prophylaxis.
- No prophylactic systemic antibiotics; treat proven infection.
Restlessness in a fresh major burn may be due to hypoxia or hypovolaemia, not pain. Correct these before giving sedatives or opioids.
Escharotomy
A circumferential full-thickness burn forms a stiff, inelastic eschar. As tissue swells underneath, it acts like a tourniquet:
- On a limb: compartment pressure rises, threatening the limb (pain, paraesthesia, poor capillary refill; pulses are lost late).
- On the chest: restricts breathing (rising airway pressure, CO2 retention).
Escharotomy means cutting through the full thickness of the eschar to release it.
| Site | Placement |
|---|---|
| Upper limb | Mid-axial lines; medially pass in front of the elbow to protect the ulnar nerve |
| Hand and fingers | Specialist procedure in theatre |
| Lower limb | Mid-axial lines; medially pass behind the ankle to protect the saphenous vein |
| Chest | Down each side (lateral to the nipples, anterior axillary line) joined by cross-cuts below the clavicles and at the costal margin |
- It is painless because nerve endings in full-thickness eschar are destroyed, but it can bleed; use diathermy and haemostatic dressings.
- Fasciotomy is needed when muscle itself is swollen: high-voltage electrical injuries, crush or associated fractures.
Emergency treatment of a circumferential full-thickness burn of a limb (after resuscitation) is escharotomy, not dressings or excision.
Wound care
Cleaning and blisters
- Clean with chlorhexidine solution or saline.
- Blisters: opinion is divided; small intact blisters can be left, but large or broken blisters should be removed (debrided).
Dressings and topical agents
Superficial (partial-thickness) burns heal on their own within about 2 weeks almost whatever dressing is used. Choose simple, non-adherent, painless dressings:
- Paraffin (Vaseline) gauze or silicone mesh with absorbent layers.
- Hydrocolloid dressings (moist environment, changed every few days); useful in mixed-depth burns.
- Biological or synthetic dressings such as Biobrane (nylon mesh with porcine collagen and silicone outer layer) for fresh, clean superficial burns.
- Exposure method: let the burn dry into a crust; used for the face and in hot climates, but needs intensive nursing.
Deep dermal and full-thickness burns need antibacterial topical agents to delay colonisation before surgery:
| Agent | Points to remember |
|---|---|
| Silver sulfadiazine 1% (Flamazine) | Most widely used; broad cover including Pseudomonas and MRSA; avoid in pregnancy, breastfeeding and infants under 2 months (kernicterus); can cause transient leucopenia |
| Silver nitrate 0.5% | Good against Pseudomonas; needs frequent re-soaking; stains black; can cause hyponatraemia |
| Mafenide acetate | Penetrates eschar; painful; carbonic anhydrase inhibition causes metabolic acidosis |
| Silver sulfadiazine with cerium nitrate | Forms a firm, sterile eschar; useful when surgery is delayed or not planned |
| Nanocrystalline silver dressings | Release silver slowly; fewer dressing changes |
A burn that is not healed by 3 weeks with conservative care is too deep; it needs excision and grafting, or it will heal with bad hypertrophic scarring.
Surgery for the burn wound
- Apart from tiny areas (under about 4 cm²), deep dermal and full-thickness burns need surgery.
- Reassess burns of uncertain depth at 48 hours.
- Early excision and grafting (within the first few days) removes dead tissue, reduces infection and the catabolic drive, shortens stay and improves scars.
| Technique | Used for |
|---|---|
| Tangential excision (shaving) | Deep dermal burns: shave thin layers until punctate bleeding from healthy dermis, then graft |
| Full-thickness (fascial or fat-level) excision | Full-thickness burns, down to viable fat or fascia |
| Split-thickness skin grafting | Standard cover; meshed grafts for large areas |
| Temporary cover | Cadaver skin (allograft), artificial dermis (e.g. Integra) when donor sites are short in massive burns |
- Blood loss is large: use dilute adrenaline infiltration and soaks, tourniquets on limbs, and keep the patient warm (core temperature above 36 °C).
- Splint in a safe position: hand in the position of function, knees extended, axilla abducted. Physiotherapy from day 1.
Infection, nutrition and support
- Burns patients are immunosuppressed; sources include the wound, lungs, lines, catheters and gut.
- Common organisms: Staphylococcus aureus, Pseudomonas aeruginosa (blue-green discharge), streptococci, and fungi in large burns. Group A streptococcus can destroy grafts.
- Signs of infection: rising or falling white cell count, thrombocytosis, worsening catabolism, fever above about 38.5 °C, a burn that deepens.
- Infection can turn a superficial burn into a deeper one.
- Feed early (enteral, nasogastric) to meet hypermetabolic needs; stress-ulcer prevention.
- Psychological support; post-traumatic reactions are common.
Late problems and reconstruction
- Hypertrophic scars: pressure garments worn for 6–18 months, silicone sheets, intralesional steroid, massage.
- Contractures: release with Z-plasty (single band), transposition flaps, full-thickness grafts or flaps for wide areas. Eyelid contractures must be released early to prevent exposure keratitis.
- Itching: antihistamines, moisturisers, gabapentin in severe cases.
- Marjolin's ulcer: SCC in an old unstable burn scar, years later.
- Burn alopecia: tissue expansion of hair-bearing scalp.
Electrical burns
Types
| Type | Features |
|---|---|
| Low voltage (under 1000 V; domestic) | Small, deep entry and exit burns (often fingers); AC causes muscle tetany so the victim cannot let go; main risk is cardiac arrest from disturbed rhythm, usually without lasting heart muscle damage |
| High voltage (1000 V or more) | Massive damage along the current path; deep muscle necrosis under normal-looking skin; direct myocardial injury |
| Flash / arc burn | Current passes outside the body; heat flash burns exposed skin; may ignite clothing |
| Lightning | Very high voltage, very short; cardiac or respiratory arrest; fern-like skin marks |
Pathophysiology
- Tissues with high resistance (bone) generate the most heat; deep tissue around bones cooks while the skin cools faster, so skin wounds underestimate the damage.
- Current runs along vessels and nerves: thrombosis and nerve injury.
- Muscle necrosis → myoglobinuria → acute kidney injury; compartment syndrome; hyperkalaemia and metabolic acidosis.
- Violent muscle spasm can cause fractures and dislocations (e.g. spine, shoulder).
Management
- Secure the airway, IV line in an uninvolved limb, ECG and cardiac monitoring (prolonged monitoring if there was loss of consciousness, high voltage, abnormal ECG or arrhythmia), urinary catheter.
- Do not rely on % TBSA to calculate fluid; give more. ATLS starts at 4 mL × kg × % TBSA, aiming for urine about 100 mL/h in adults (1–1.5 mL/kg/h in children under 30 kg) until the urine clears; Bailey & Love advises keeping urine output high (up to 2 mL/kg/h).
- Dark red urine means myoglobin: treat at once without waiting for tests; bicarbonate or mannitol only after specialist advice.
- Check repeatedly for compartment syndrome: fasciotomy; early debridement; sometimes primary amputation.
- Transfer to a burns unit.
A clenched hand with a small entry wound after a high-voltage injury means extensive hidden muscle damage. Watch for myoglobinuria, arrhythmia and compartment syndrome.
A 70 kg man with a high-voltage injury and 10% TBSA visible burns.
Starting volume = 4 × 70 × 10 = 2,800 mL in 24 h, then increase as needed to keep urine about 100 mL/h until it is clea
Chemical burns
Pathophysiology
- Damage continues as long as the chemical stays in contact; severity depends on concentration, amount and contact time.
- Two problems: local corrosion and systemic poisoning after absorption.
| Feature | Acid | Alkali |
|---|---|---|
| Type of necrosis | Coagulative: forms a barrier that limits penetration | Liquefactive: dissolves tissue and penetrates deeper |
| Severity | Weak acids superficial; strong acids deep | Usually more serious (e.g. cement, oven cleaners, lime) |
| Eye injury | Serious | Very serious; irrigate continuously |
Management
- Protect yourself (gloves, gown).
- Remove contaminated clothing; brush off dry powder first.
- Copious irrigation with water for at least 20–30 minutes (ATLS); longer for alkalis. Eyes need continuous irrigation.
- Do not use neutralising agents: the reaction produces heat and more damage.
- Identify the chemical (container, safety data sheet, poison centre) and look for systemic toxicity.
- Then treat as a thermal burn of the same depth.
Special chemicals:
| Chemical | Special treatment |
|---|---|
| Hydrofluoric acid | Fluoride ions bind calcium: severe pain, deep tissue damage, hypocalcaemia and hypomagnesaemia with arrhythmias. Treat with calcium gluconate gel topically; regional (Bier's block) or local calcium gluconate for larger hand burns; monitor calcium and ECG; early excision for concentrated acid burns |
| Phosphorus (military devices) | Water helps, but particles must be removed physically; they ignite in air |
| Elemental sodium / metals | Do not wet; remove with forceps or cover with oil |
| Tar / bitumen | Cool rapidly; dissolve with mineral oil or paraffin, do not peel off |
For chemical burns, "dilution is the solution": water, lots of it, early. The exceptions are dry powders (brush first) and reactive metals.
Cold injury (brief)
- Frostbite: rapid rewarming in a water bath at about 40–42 °C; surgery is delayed until the dead tissue has clearly demarcated.
Expect: cooling with running water as first aid, ABC with early intubation for airway burns, escharotomy for circumferential full-thickness burns (mid-axial, painless), silver sulfadiazine as the commonest topical agent and its contraindications, exposure or simple dressings for superficial burns, tangential excision and split-skin grafting for deep dermal burns, the 3-week rule, pressure garments for hypertrophic scars, IV not IM analgesia, high- versus low-voltage electrical injury with hidden muscle damage, myoglobinuria and higher urine targets, and water lavage for chemical burns with calcium gluconate for hydrofluoric acid.
Quick revision
- First aid: stop burning, cool running water at least 10 minutes, keep patient warm, cover.
- ABCDE + fluids; IV opioids, not IM; tetanus; no prophylactic antibiotics.
- Circumferential full-thickness burn: escharotomy (mid-axial; chest pattern for breathing).
- Silver sulfadiazine 1%: commonest; Pseudomonas cover; avoid in pregnancy and infants under 2 months.
- Superficial burns: simple dressings, heal by 2 weeks.
- Deep dermal: tangential excision and split-skin graft; not healed by 3 weeks means graft.
- Hypertrophic scar: pressure garments 6–18 months.
- Electrical: 1000 V threshold; hidden muscle necrosis, myoglobinuria, arrhythmias, fasciotomy.
- Chemical: copious water 20–30 minutes; alkali worse; hydrofluoric acid needs calcium gluconate.
Written by The House Job from standard surgical references (Bailey & Love; ATLS Student Course Manual).
FAQ
How long should a burn be cooled?
With cool running water for at least 10 minutes, ideally as soon as possible, and it is still worth doing up to about an hour after the injury. Keep the rest of the patient warm.
Why is escharotomy not painful?
Full-thickness burns destroy the nerve endings in the skin, so cutting through the eschar causes little pain, although bleeding can be significant.
Why are alkali burns worse than acid burns?
Alkalis cause liquefactive necrosis, which dissolves tissue and lets the chemical penetrate deeper, while acids cause coagulative necrosis that partly limits spread.
Why do high-voltage electrical burns need extra fluid?
Hidden muscle damage releases myoglobin that can block the kidneys, so a higher urine output is needed until the urine is clear, and surface burn area underestimates the injury.