... may be partial or complete and occur at any level. In the unconscious patient, the commonest site of obstruction is the pharynx, which most commonly is occluded by the tongue but sometimes by other structures in the neck such as the epiglottis or soft palate. Obstruction may also caused by vomit, blood or foreign material because of trauma. Laryngeal obstruction may occur as of a result of oedema "spasm" or an inhaled foreign body. Obstruction of the airway below the larynx is less common but may occur because of excessive bronchial secretions, mucosal oedema, bronchospasm, and pulmonary oedema, aspiration of gastric contents or pulmonary haemorrhage and pneumothorax secondary to thoracic trauma. RECOGNITION OF AIRWAY OBSTRUCTION This is best achieved by the "look, listen and feel" approach - Look - for chest and abdominal movement. Listen/Feel - for airway flow at the mouth and nose. In partial obstruction, air movement is diminished and usually noisy. ...

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