A burn is defined as an injury caused by thermal, chemical, radiation or electrical energy.
Thermal burn is the most common cause of burns. Not only does it cause damage to the skin, it also carries a risk of inhalation injury. An inhalation injury refers to a burn anywhere in the respiratory tract, from the pharynx to the lungs. The signs of inhalation injury include singed nasal hairs, carbon particles in the sputum, hoarseness and elevated carbon monoxide levels in the blood. If there is concern about significant airway injury, anaesthetic input should be sought early, as an endotracheal tube may be required. Swelling of the airway worsens over the first 24-48hrs after acute injury, making intubation much more difficult.
Electrical burns cause injury by a combination of thermal injury and the direct effects of the electrical current to the tissues. They are often more serious than they may appear on the surface. Muscle is typically the most affected in this sort of injury and there is a risk of compartment syndrome (swelling of muscle groups leading to myonecrosis). Significant muscle damage leads to myoglobinuria which can cause acute kidney injury.
Chemical burns cause damage by reacting to the tissue proteins which ultimately leads to tissue death. Chemicals that remain in contact with the skin will continue to cause damage until they are removed or neutralised.
- Annually, in the UK, approximately 175,000 people attend A&E departments with burn injuries
- 10% of these patients require inpatient care in a specialist burns unit
Assessment of major burns should follow the ATLS approach
Your first priority is the patient’s airway:
- Identify whether there is inhalation injury
- Treat any airway obstruction
- If there is evidence of impending airway obstruction (hoarseness, stridor) involve an anaesthetist immediately
Once the airway is safe/secure:
- Stop the burning process by removing all clothing from the affected area (do not peel off adherent clothing)
- Rinse with copious amounts of warm tap water
- Cover the area with saline soaked gauze
- Gain intravenous access – patients with burns over more than 20% of the body surface area will require fluid resuscitation
Establish the circumstances within which the injury occurred (this, of course, should not delay resuscitation efforts):
- How did the fire occur? (e.g explosion)
- Where did it occur?
- Was it an enclosed space? (e.g. risk of carbon monoxide exposure)
- When was the patient removed from the fire and how long were they exposed to it?
- Any loss of consciousness?
- Did the patient fall or jump? (exclude other injuries)
- Enquire about the patient’s past medical history and tetanus status
Total burn surface area (TBSA) can be estimated using Wallace’s Rule of Nines. In this system, the adult body is divided into anatomical regions that represent 9% (and multiples of 9%) of the TBSA. This is useful for a quick clinical assessment.
For children, because their heads are larger in relation to their bodies, the rule must be modified to account for this. Lund and Browder charts are commonly used to perform this estimation. The method is more accurate and allows for age variation.
Burns are classified as first, second and third degree depending on the depth of the injury.
Superficial (1st-degree burn)
Injury to the superficial surface of the skin (like a sunburn). The epidermis remains intact. Features include erythema, pain and absence of blisters. Normally heals within 1-2 weeks with no scarring.
Partial thickness (2nd-degree burn)
Involves the dermis which can range from superficial dermal to deep dermal. Blisters, severe pain, hypersensitivity and weeping skin are features. Takes 2-8 weeks to heal (depending on depth).
Full thickness (3rd-degree burn)
Complete destruction of the dermis and may extend to the subcutaneous tissue. Clinical features include a thick leathery feel, pallor, loss of sensation and absent capillary refill. This type of burn usually requires skin grafting and surgical management.
Involves the subcutaneous fat, muscle and sometimes bone. May require amputation.
Burns tend not to be uniform, there may be areas of 1st, 2nd, 3rd-degree burns in any given area.
They are also dynamic and need constant reassessing in the first 48 to 72 hours as their depth can change due to inadequate treatment or superadded infection.
- Should be secured as part of your initial treatment
- Hypoxia should be managed with supplemental oxygen
- Carbon monoxide (CO) exposure can occur in an enclosed space
- Measure HbCO (carboxyhaemoglobin) levels
- Levels greater than 20% can cause: headache, confusion, coma and death
Fluid resuscitation is usually required in a patient with severe burns. The following formula can be used to work out fluid requirements in the first 24 hours.
First 24 hrs = 2-4mL kg of crystalloid (Ringer’s Lactate) × patient weight (kg) × % BSA (area of burn)
Half of this amount should be given in the first 8 hours and the rest over the next 16 hours, but urine output should also guide fluid prescribing.
Monitor urine output and test for myoglobinuria, which can cause acute renal failure.
Bloods: FBC, U&E, Crossmatch, Carboxyhemoglobin, Serum glucose, Pregnancy test in all females of childbearing age
Imaging: CXR and other imaging as deemed appropriate
Cardiac monitoring: to monitor for the effects of electrolyte and acid-base abnormalities
Gastric tube insertion
May be required if there is nausea, abdominal distention, or if there is an extensive burn greater than 20%.
Burns are one of the most painful injuries one can have.
Looking after and treating burns can mean patients are often in constant pain.
Intravenous morphine is usually required.
Dressings help to relieve pain by preventing air from passing over the wounds which can be very painful.
Paraffin gauze dressings are a good option in superficial burns and silver nitrate dressings are preferred for deeper ones.
Recovery will depend on the depth of the burns and the body surface area affected.
Superficial burns usually take 14 days to heal without surgical intervention.
People most at risk of death are those over 60 years, greater than 40% of burn surface area affected and inhalation injury.
Mr Zakir Shariff
Consultant Plastic Surgeon
1. Wallace’s Rule of Nines. By OpenStax College [CC BY 3.0], via Wikimedia Commons
2. By U.S. Department of Health and Human Services (http://www.remm.nlm.gov/burns.htm) [Public domain], via Wikimedia Commons
3. By QuinnHK at English Wikipedia [Public domain], via Wikimedia Commons
4. By Snickerdo at Wikipedia [CC-BY-SA-3.0], via Wikimedia Commons
5. By Craig0927 (Own work) [Public domain], via Wikimedia Commons
6. By goga312 at Wikipedia [CC BY-SA 3.0], via Wikimedia Commons
Semer NB. Practical Plastic Surgery for Nonsurgeons. Hanley & Belfus, Inc. Philadelphia. 2001
Wyatt JP. Oxford Clinical Handbook of Emergency Medicine. OUP Oxford; 4th ed. 2012
American College of Surgeons. Advanced Trauma Life Support: Student Course Manual. American College of Surgeons. 9th ed. 2012
Enoch S, Roshan A, Shah M; Emergency and early management of burns and scalds. BMJ. 2009 Apr 8 338:b1-37.doi:10.1136/bmj.b1037
Henderson R. Burns – assessment and management. patient.co.uk. 2015 Jul 24 1896 (v25)