Burns

01OverviewDefinition, clinical context and the essential points that orientate the chapter.

A burn is both a local tissue injury and, when sufficiently extensive, a systemic insult. Depth determines healing potential and the likelihood of grafting, while area influences fluid loss and physiological burden. Special sites such as hands and joints can produce major functional disability despite a small surface area. Early assessment therefore records more than a percentage: mechanism, time, depth, distribution, pain, circulation and associated injuries all matter.

The first priorities are stopping further damage, treating life-threatening associated problems and preserving viable tissue. Cooling should be targeted to the injured area while the rest of the patient is kept warm. Later care involves wound reassessment, dressings, analgesia, rehabilitation and sometimes surgery. A wound that initially appears superficial can evolve, so a clear review plan is part of treatment rather than an optional precaution.

Key points

Stop the burning process safely and remove constricting jewellery or clothing that is not adherent.
For thermal burns, provide 20 minutes of cool running water as soon as possible, ideally within three hours; prevent whole-body hypothermia.
Avoid ice, iced water, butter, creams and gels as first aid; do not peel off material stuck to the wound.
Estimate total body surface area using partial-thickness and full-thickness injury, excluding simple erythema.
A small external burn does not exclude serious smoke inhalation, carbon monoxide poisoning or electrical injury.
Discuss depth, site, mechanism, size and the patient’s condition with the burn service; a percentage threshold alone cannot determine safe discharge.

02AetiologyUnderlying causes, associations and risk factors, with why each one matters.

Thermal injury

Flame, scald and contact burns transfer heat into tissue. Exposure duration and temperature influence depth; hot clothing or adherent material can prolong contact until the burning process is safely stopped.

Chemical and electrical injury

Chemicals may continue damaging tissue until appropriately removed or diluted. Electrical energy can produce deep muscle and vascular injury that is poorly represented by the visible skin wounds.

03PathophysiologyThe causal sequence from the underlying abnormality to symptoms and harm.

1
Progressive tissue damage
The central burn may be irreversibly damaged while adjacent tissue remains vulnerable to reduced perfusion and inflammation. Prompt cooling and avoidance of hypoperfusion help limit additional tissue loss.
2
Capillary leak
Extensive burns increase vascular permeability and shift fluid into interstitial tissues. Resuscitation must maintain organ perfusion while avoiding excessive oedema from uncritical continuation of formula-based fluid volumes.
3
Loss of skin function
Damage to the skin barrier impairs heat conservation and protection from infection. Exposed wounds also cause pain and fluid loss, making appropriate covering, temperature control and subsequent wound care necessary.

04Clinical features and red flagsSymptoms, examination findings, patterns of presentation and time-critical warnings.

Depth at the bedside

A superficial dermal injury is usually painful, moist and blanching, whereas deeper injury may be pale, dry, less sensitive or non-blanching. A painless area can therefore be more concerning, not reassuring; mixed depths commonly coexist.

Extent and distribution

Use a Lund–Browder chart when available and document the affected areas. For small scattered burns, the patient’s whole palmar surface including fingers approximates one percent, but this estimate should not replace careful assessment of larger injuries.

Inhalation and enclosed-space exposure

Ask about entrapment, smoke, loss of consciousness and breathing symptoms. Voice change, stridor, facial or oral injury and soot warrant early experienced airway assessment, with particular concern when swelling is progressing.

Circumferential and electrical injury

A constricting deep burn may impair limb perfusion or chest expansion as oedema develops. Electrical injury can damage deeper tissues beyond the visible contact wounds, so assess rhythm, muscle injury and associated trauma.

05InvestigationsWhat to request, why it matters and how to interpret it.

Investigation order

Read from the initial assessment onwards. Tests may run in parallel in urgent care; first-line, preferred, confirmatory, definitive and gold-standard labels appear only when the chapter explicitly states them.

01
Burn chart and serial wound examinationFirst step
Why
Define initial extent and identify depth progression or threatened function.
Interpretation and limitations
Record depth and body-surface estimate separately, excluding uncomplicated redness. Photographs require appropriate consent and secure clinical handling; they support specialist discussion but cannot assess sensation or perfusion by themselves.
02
Blood gas with co-oximetry
Why
Assess acidaemia and identify carbon monoxide exposure after smoke inhalation.
Interpretation and limitations
Standard pulse oximetry can appear reassuring despite carboxyhaemoglobin. Interpret the measured level with elapsed time and oxygen already given, while treating the exposure and arranging specialist advice.
03
Electrolytes, renal function and creatine kinase
Why
Monitor resuscitation and detect muscle injury, especially after electrical burns.
Interpretation and limitations
Rising creatinine, potassium or creatine kinase can indicate deeper injury and renal risk. The absence of extensive skin damage does not exclude clinically important rhabdomyolysis.
04
ECG and selected imaging
Why
Investigate electrical or associated traumatic complications and guide respiratory assessment.
Interpretation and limitations
Obtain an ECG after relevant electrical exposure and use injury-specific imaging where indicated. A normal early chest radiograph does not exclude evolving inhalation-related lung injury.

06Differential diagnosisRealistic alternatives and the features that help distinguish them.

Superficial erythema versus dermal burn

Simple erythema lacks the dermal injury used in resuscitation surface-area estimates. Blistering, altered blanching and sensation help identify deeper involvement, with reassessment required when the initial depth is unclear.

Smoke toxicity versus airway swelling

Carbon monoxide or other inhaled toxins can impair consciousness without major upper-airway obstruction. Airway burns may instead progress mechanically; both can coexist and need separate assessment and treatment.

Associated trauma

Falls, explosions and escape attempts can produce fractures or internal bleeding alongside a burn. Examine beyond the wound and reconsider the cause when the physiological disturbance exceeds the apparent burn burden.

07ManagementImmediate care, first-line treatment, alternatives and escalation.

01Worked caseA major scald and a time-sensitive fluid calculationFirst stepA 70 kg adult arrives two hours after a 20% partial-thickness scald. Five hundred millilitres of resuscitation crystalloid has already been given; the burns team selects its 4 mL/kg/%TBSA Parkland starting protocol.

1Complete airway and trauma assessment, finish indicated cooling without chilling the patient, cover the injury and obtain effective analgesia. Confirm that 20% describes dermal injury rather than surrounding redness.
2Calculate the protocol’s first-day estimate: 4 × 70 × 20 = 5,600 mL. Half, 2,800 mL, is allocated to the first eight hours from injury; the remaining half is allocated to the subsequent sixteen hours.
3Subtract the 500 mL already administered from the first-eight-hour allocation. With six hours remaining, the illustrative starting rate is 2,300 ÷ 6, approximately 383 mL/hour, subject to the burn team’s reassessment.
4Use balanced crystalloid and record urine output, perfusion, respiratory findings and all other fluid intake. Check that the pump rate and elapsed injury time match the calculation, then reassess hourly rather than treating the formula as a fixed entitlement.
5The patient’s perfusion improves, but urine output falls and the cannula site swells. Check delivery and catheter function, reassess the patient and obtain senior review; simply increasing a formula-derived rate could miss extravasation or another cause.

02Airway branchDeterioration after an enclosed-space fireAn adult rescued from a smoke-filled room develops increasing hoarseness, oral swelling and respiratory effort despite a small cutaneous burn.

1Give high-concentration oxygen, call anaesthesia and the burns service immediately, and prepare a controlled expert airway strategy before swelling makes access more difficult.
2Obtain co-oximetry and blood gas while resuscitation continues. Consider toxic smoke exposure, including cyanide in severe compatible presentations, and request NPIS advice without delaying airway care.
3Reassess oxygenation, ventilation, haemodynamics and the response to airway intervention. Arrange transfer with a team capable of managing a potentially difficult airway and evolving respiratory failure.

03Minor-burn branchDisposition after initial wound careA stable adult has a small thermal burn without airway or circulatory compromise.

1Assess depth, special-site involvement, circumferential injury, mechanism, comorbidity and safeguarding concerns. Under national referral guidance, adult burns of at least 3% or any full-thickness injury warrant specialist referral, with discussion for special sites or uncertain injuries.
2After cooling, use an appropriate non-adherent dressing or loose longitudinal cling-film strips for initial covering; never apply cling film circumferentially or over the face. Arrange wound-specific analgesia and tetanus assessment.
3EscalationGive explicit review instructions for increasing pain, spreading erythema, discharge, fever or loss of movement or sensation. Escalate a burn not healed by two weeks to a specialist service and arrange earlier reassessment when depth is uncertain.

Key medicines and prescribing safety2 treatments · regimens, roles and cautions

Replace the substantial intravascular losses associated with an extensive dermal burn.

Balanced crystalloid for major burn resuscitation

Use the receiving burns service’s named protocol. The NHS Lothian adult example starts with 4 mL × actual weight in kg × %TBSA over 24 hours, half in the first 8 hours from injury, then titrates to clinical response.

Formulae differ between services and are starting estimates. Account for fluid already given, prescribe concurrent maintenance or enteral intake separately, monitor urine output and avoid excessive fluid causing worsening oedema.

Provide prompt relief of severe acute burn pain while assessment, covering and resuscitation proceed.

IV morphine for severe burn pain

An example from RCHT is morphine 10 mg diluted to 10 mL with sodium chloride 0.9%, then 2 mg IV boluses every 2–5 minutes with reassessment until comfortable or the individual prescribed maximum is reached. Restrict this to initial pain control and review the subsequent analgesic prescription.

Use smaller initial amounts in frailty; this protocol advises an alternative opioid when eGFR is below 30 mL/min/1.73 m². Monitor consciousness, breathing, blood pressure and oxygen saturation every 5 minutes and for 15 minutes after the last dose. Stop escalation for excessive sedation, impaired ventilation or hypotension, and count earlier opioid doses.

08ComplicationsImportant consequences, why they occur and why they matter clinically.

Airway and respiratory failure

Progressive upper-airway swelling or lower-respiratory injury can require advanced support. Early expert assessment is important when the clinical course suggests that later airway management will become more difficult.

Renal and compartment injury

Hypoperfusion and rhabdomyolysis may impair kidney function. Deep circumferential burns and excessive oedema can threaten limb circulation or ventilation, requiring urgent specialist intervention rather than analgesia alone.

Scarring and disability

Deep wounds may heal with hypertrophic scars and contractures that restrict function. Appropriate surgical assessment, therapy, wound review and psychological support extend treatment beyond the initial resuscitation period.

09Monitoring and follow-upTreatment response, safety checks and longer-term review.

Record temperature during cooling and transfer; prevent hypothermia by insulating unburned areas and avoiding prolonged whole-body exposure.
For major burns, chart hourly urine output, fluid delivered and perfusion, investigating poor response rather than repeatedly increasing fluid without examining the patient.
Repeat distal circulation, sensation and movement in circumferential limb burns, and seek urgent expert assessment if swelling threatens perfusion.
Review analgesic response, wound appearance, range of movement and healing progress; make dressing follow-up and rehabilitation responsibilities explicit.

10Special situationsVariants, exceptions and circumstances that change the usual approach.

Immediate hypotension may have another cause

Profound shock very soon after a burn should prompt a search for associated haemorrhage or another mechanism. Do not attribute every circulatory abnormality to delayed burn-related capillary leak.

Chemical exposure needs agent-specific care

Protect staff and remove contaminated clothing; brush away dry powder before irrigation where appropriate. Seek NPIS guidance because some agents require specific decontamination and antidotal treatment.

Routine antibiotics are not burn first aid

A clean thermal burn does not by itself justify systemic prophylactic antibiotics. Assess suspected infection clinically and use a burn-service antimicrobial plan when treatment is indicated.

Function matters beyond wound closure

Hand, joint and facial injuries may need early specialist therapy to preserve movement and reduce contracture. Discuss practical dressing care, work and psychological effects during follow-up.

11Common pitfallsFrequent interpretation and management errors.

01
Do not replace twenty minutes of appropriate running-water cooling with gel dressings or ice, even if those products are readily available.
02
Do not include simple erythema in the percentage used for a major-burn fluid calculation, or restart the first-eight-hour clock on hospital arrival.
03
Do not judge burn severity from pain alone: loss of sensation may indicate deep tissue destruction.
04
Do not discharge on size alone when the burn is deep, involves a critical site, has an unusual mechanism or raises safeguarding concerns.

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