Abstract

Twenty-eight patients who required endotracheal intubation for open-heart surgery were randomly allocated to one of two types of endotracheal tube. The tracheal mucosa was examined with a fibreoptic bronchoscope at the time of extubation, usually 24 hours after operation. The degree of oedema, inflammation, and ulceration was scored by the bronchoscopist, who also photographed the whole length of the trachea. An independent observer subsequently scored any tracheal damage from these photographs. Both observers found significantly less mucosal damage with the low-pressure, high-volume type of cuff than with the traditional high-pressure, low-volume type. This difference may be related to the differences in lateral wall pressures exerted by the two types of cuff. The low-pressure type of cuff may be preferable in patients requiring prolonged endotracheal intubation.