Outline the pathophysiology and clinical features of a smoke inhalation injury in a patient with major burns.
Key Features
a) CO/CN toxicity – Lactic acidosis, high SvO2, mental confusion, hypotension
b) Upper airway obstruction from airway oedema – soot in the pharynx, singed hair, stridor, hoarseness, oropharyngeal erythema, oedema and blistering
c) Chemical burns to the lungs which result in mucosal damage, bronchitis, mucous plugging and pulmonary oedema – Bronchospasm, bronchorrhoea, raised a-a gradient
Smoke inhalation injuries are discussed in greater detail in the answer to Question 26 from the first paper of 2012. One can divide this issue into mechanisms of thermal and inhalational injury, pathophysiological changes, damage at varying anatomical levels, and probably all of the above are reasonable approaches.
Presented in this fashion, it could even be turned into a table.
Everyone likes tables.
Mechanism |
Specific factors |
Clinical features | Management |
Thermal |
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Inflammatory |
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Inhaled agents |
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Or, one can organise them by anatomical location:
Anatomical location |
Mechanism |
Clinical features | Management |
Face |
|
|
|
Oral cavity |
|
|
|
Pharynx |
|
|
|
Larynx |
|
|
|
Trachea |
|
|
A good summary of airway burns can be found in this 2012 article
Lund, Tjostolv, et al. "Upper airway sequelae in burn patients requiring endotracheal intubation or tracheostomy." Annals of surgery 201.3 (1985): 374.
Bartlett, Robert H., et al. "Acute management of the upper airway in facial burns and smoke inhalation." Archives of Surgery 111.7 (1976): 744-749.
Gaissert, Henning A., Robert H. Lofgren, and Hermes C. Grillo. "Upper airway compromise after inhalation injury. Complex strictures of the larynx and trachea and their management." Annals of surgery 218.5 (1993): 672.
Bishop, Sophie, and Simon Maguire. "Anaesthesia and intensive care for major burns." Continuing Education in Anaesthesia, Critical Care & Pain 12.3 (2012): 118-122.