Show Summary Details
Page of

Upper airways obstruction 

Upper airways obstruction

Upper airways obstruction

J.R. Stradling

and S.E. Craig

Page of

PRINTED FROM OXFORD MEDICINE ONLINE ( © Oxford University Press, 2015. All Rights Reserved. Under the terms of the licence agreement, an individual user may print out a PDF of a single chapter of a title in Oxford Medicine Online for personal use (for details see Privacy Policy).

date: 28 April 2017

At resting levels of ventilation, the main airway can be reduced to a diameter of 3 mm or so before respiratory distress and stridor occur. Little more narrowing is required to precipitate complete asphyxia, hence when upper airways obstruction is suspected, assessment of severity, diagnosis, and treatment is a medical emergency.

Clinical features and diagnosis—recognizing the presence of upper airways obstruction requires a high degree of clinical suspicion: stridor or noisy breathing will initially only be heard on exercise, but will gradually appear at lower and lower levels of activity; a patient’s complaint that the problem is ‘somewhere in the neck’ should be taken seriously.

Investigation—peak expiratory flow rate is reduced disproportionately to the forced expiratory volume in 1 s (FEV1), but the best functional evidence of upper airways obstruction is obtained with a flow–volume loop, which shows a squared appearance.

Acute upper airway obstruction—this can be caused by aspiration, oedema (allergic, hereditary, and acquired angio-oedema, smoke inhalation), and infection (more commonly in children). The emergency treatment for aspiration is the Heimlich manoeuvre (abdominal thrust); allergic causes require intramuscular adrenaline (0.5 ml of 1:1000, and see Chapter 17.2 for details of the management of anaphylaxis). Intubation or emergency cricothyroidotomy (in rare cases) may be required.

Nonacute upper airway obstruction—this can be caused by tumours, tracheal stenosis (usually after intubation or tracheostomy), tracheal compression, various tracheal abnormalities, and laryngeal dysfunction. Spread of a primary bronchial carcinoma into the base of the trachea is probably the commonest cause. This unfortunately becomes a terminal event in many cases, when adequate sedation must be given to make the patient unaware that they are asphyxiating and choking to death.

Access to the complete content on Oxford Medicine Online requires a subscription or purchase. Public users are able to search the site and view the abstracts for each book and chapter without a subscription.

Please subscribe or login to access full text content.

If you have purchased a print title that contains an access token, please see the token for information about how to register your code.

For questions on access or troubleshooting, please check our FAQs, and if you can't find the answer there, please contact us.