SummaryIncreased tracheal cuff pressure during mechanical ventilation is associated with reduced mucosal blood flow and ischaemia, as well as postoperative sore throat. We assessed the potential effects of transoesophageal echocardiography probe insertion on the tracheal cuff pressure in patients undergoing cardiac surgery. Using a manometer, the cuff pressure of a high-volume, low-pressure tracheal tube (inner diameter 7.0 mm for women and 7.5 mm for men) was adjusted to 25-30 cmH 2 O before blind insertion of a transoesophageal echocardiography probe. The pressure changes were then recorded for 1 min. After probe insertion, the mean (SD) intra-cuff pressure increased from 27.7 (1.5) to 36.2 (6.4) cmH 2 O (p < 0.001) and was > 35 cmH 2 0 in 17 ⁄ 38 patients (45%). Our results suggest that transoesophageal echocardiography probe insertion may increase the tracheal cuff pressure more than that is generally recommended and therefore the latter should be routinely monitored under such circumstances.