THE RISK OF ASPIRATION IN PRESENCE OF CUFFED ENDOTRACHEAL TUBES

The risk of aspiration was determined in 90 adult patients undergoing surgery during endotracheal anaesthesia. Twenty ml of contrast medium was instilled on the back of the tongue in patients lying supine on the operating table after obtaining an airtight seal in the trachea by inflating the cuff of the endotracheal tube. In 18 patients contrast medium passed through the larynx and accumulated in the trachea above the inflated cuff and entered the lungs at the end of the operation when the cuff was deflated. This aspiration can be prevented by placement of the cuff just beyond the true vocal cords, or by tilting the operating table 10 degrees head down before deflating the cuff and applying suction through the endotracheal tube. It is often taken for granted that cuffed endotracheal tubes provide an absolute guarantee against the danger of aspiration of stomach contents and pharyngeal secretions into the lungs. In the past, several workers have carried out radiological investigations to ascertain the incidence of aspiratio