#7519 - Burns - Medical Finals & OSCEs Notes

Burns

6% of burn victims have an inhalational injury. There is twice the chance of death if there is inhalational injury.

80% have flame burns ( v deep and serious) or scalds (usually children)

Causes

Flare, scald, contact, frostbite, chemical (acid or alkali), electrical (high/low voltage).

Alkali burns more deeply than acid: acid coagulates proteins so stops itself, alkali liquefies tissues so keeps going.

Electricitymuscles contract, flexors stronger than extensors, so flex extremely strongly.

Electricityall conducting tissue, nerves so completely die anaesthesia; heart so arrhythmias; muscles so they swell.

Feed patients with big burns early as microbial translocation in the gut occurs due to the large-scale intestinal barrier loss of the gut, and they are also in a very catabolic state, for months afterwards too.

Dx

Hx- enclosed space? breathing smoke, CO etc. Found unconscious? length of time trapped

O/E – face burns, oral/nasal burns, carbonaceous sputum, hoarse, stridor.

Ix –

• CO poisoning, do not use sats probe (which detects carboxyhaemoglobin so gives a false reading). Look for ‘cherry red’ tongue and bounding pulse

• PaO2 is usually normal as the same amount of oxygen is dissolved in the blood.

• But SaO2 decreases as CO is bound.

• PaCO2 is normal (or down to an increased RR)

• Decreased pH

• Increased lactate (anaerobic respiration)

• Thus a metabolic acidosis

Resuscitation (get to ITU and get senior help and call Regional Burns Unit early)

A:

• Thermal burn to upper airway, direct damageoedema closes off. Therefore prophylactically intubate them before the airway closes off in a few hours

• Intubate early and ventilate and give 100% O2.

• Look for cervical spine injury e.g. if they jumped out of a building

B:

• Circumferential chest burn coagulates skin proteins so skin cannot expand so lung failure occurs.

• Escharotomy = cut to release constriction. Use a diathermy to avoid further bleeding, use a scalpel if in dire straits. Cut the anterior axillary line, the front of the chest, the back, across, to get down to compliant tissue.

• Chemical burn to lower airway; inhaled ash in alveoliacute pulmonary oedema.

• They may have metabolic poisoning e.g. CO or cyanide (released from old furniture when it burns)

• 100% O2 by ventilation as they should be already intubated

C:

• They often 3^rd space and have SIRS increased capillary leakage

• >15% burn area on an adultformal IV resuscitate with the Parkland formula

• >10% burn area on children

• The Parkland formula takes into account body weight, area of burn and time since burn

• Resuscitate with IV crystalloid

• Need a huge amount – e.g. 20L over the next 24 hours for an adult with a large burn according to the Parkland formula

• Monitor: catheter, CVP, arterial line (will be on ITU anyway)

Further management

• Assess for other injuries and treat these

• Bronchoscopy when stablediagnose inhalational injury if there is carbonaceous appearance. Treat with bronchoalveolar lavage

• Intense monitoring and support

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