20.1 Burns

Question 1

You are asked to assess a 24-year-old male who has been admitted to the emergency department with
30% burns from a house fire.

a) What would lead you to suspect significant inhalational injury? (40%)

Answer 1

History:
» Fire in enclosed space.

> > Flames/fumes/smoke/steam/
superheated gases and liquids.

> > Delayed escape.

> > Loss of consciousness at scene due to drugs/alcohol/head injury/
hypoxia/carbon monoxide poisoning/
cyanide poisoning.

Symptoms and signs:
» Voice change, stridor, hoarseness.

> > Cough.

> > Burns to face, lips, tongue, pharynx.

> > Soot in sputum, nose, mouth.

> > Crackles on chest auscultation
consistent with pulmonary oedema.

> > Respiratory distress,
increased respiratory rate,
cyanosis, reduced
oxygen saturations.

> > Reduced level of consciousness, agitation.

Question 2

b) Which investigations would you use to assess the severity of the inhalational injury and what are the
likely findings? (30%)

Answer 2

> > Arterial blood gas analysis:
hypoxaemia,
raised carboxyhaemaglobin level,
lactic acidosis.

> > Venous blood gas:
decreased arteriovenous oxygen difference
(due to inability to utilise oxygen following carbon monoxide and cyanide poisoning).

>> Chest X-ray: 
may be normal,
may show atelectasis, 
pulmonary oedema,
ARDS.

> > Fibreoptic laryngoscopy (awake patient):
laryngeal oedema, mucosal
pallor or erythema and ulceration.

> > Bronchoscopy (anaesthetised patient):
carbonaceous deposits, mucosal
pallor or erythema and ulceration.

Question 3

c) List the indications for early tracheal intubation to secure the airway. (20%)

Answer 3

> > Stridor
(indicating impending airway obstruction) or actual airway obstruction.

> > Respiratory distress causing
inadequate gas exchange.

> > Hypoxaemia or hypercapnia.

> > Full-thickness neck burns.

> > Oropharyngeal oedema.

> > Low GCS.

> > Cardiac arrest.

> > Imminent transfer required and
risk of deterioration en route.

Facial swelling and oedema are likely to be significant. Use uncut tube to
accommodate this swelling and ensure that tube fixation is monitored to
ensure that the swelling does not cause the tube to migrate up and out of
the airway.

Question 4

d) How do burn injuries influence the use of suxamethonium? (10%)

Answer 4

Suxamethonium can be used 
within the first 24 hours following 
a significant burn 
(unless the patient is already 
hyperkalaemic from rhabdomyolysis) 

and then not for a year.

This is due to upregulation of
nicotinic receptors with the
consequent risk of hyperkalaemia.

There is conflicting evidence about how rapidly nicotinic receptors are upregulated, with evidence to suggest that it is safe to use suxamethonium up to six days post-burns. However, what is stated is generally accepted guidance.