Increased tracheal cuff pressure during insertion of a transoesophageal echocardiography probe

Excessive tracheal cuff pressure reduces tracheal mucosal blood flow and increases tracheal morbidity. Inserting a transoesophageal echocardiography (TOE) probe has been shown to increase tracheal cuff pressure. OBJECTIVE To evaluate the effect of inserting a TOE probe on tracheal cuff pressure and compare the effect in patients who received a single-lumen endotracheal tube (SLT) with those who received a double-lumen endotracheal tube (DLT). DESIGN A prospective, observational study. SETTING Single-centre trial, study period from October 2013 to January 2014. PATIENTS Forty-four adult patients scheduled for elective cardiothoracic surgery requiring intraoperative TOE monitoring. INTERVENTIONS After tracheal intubation with a SLT (n=22) or DLT (n=22), the tracheal cuff was inflated to 18mmHg (25cmH 2 O) with air. Tracheal cuff pressure was monitored continuously for 5min after inserting the TOE probe. MAIN OUTCOME MEASURES The primary endpoint was steady-state tracheal cuff pressure after insertion of the TOE probe. RESULTS Median (interquartile range, IQR) tracheal cuff pressure stabilised at 3 (2 to 3)min in the SLT group and at 2 (1 to 3)min in the DLT group. Steady-state cuff pressure was significantly higher in the DLT group than that in the SLT group [36.7 (31.3 to 44.1) vs. 31.3 (29.6 to 35.7) cmH 2 O; (P=0.03)]. Steady-state cuff pressure more than 40cmH 2 O was observed in two patients (18.2%) in the SLT group and nine patients (40.9%) in the DLT group (P=0.02). CONCLUSION Insertion of a TOE probe increased tracheal cuff pressure in both the SLT and DLT groups. The increase in cuff pressure was greater in patients who received a DLT. Frequent measurement and adjustment of cuff pressure should be emphasised particularly when TOE is used in patients receiving a DLT.