Air leakage around endotracheal tube cuffs

To compare the recently introduced Microcuff endotracheal tube with conventional tubes in respect of the cuff pressures required to prevent air leakage.

The following tubes (ID 7.0mm) were compared: Microcuff HVLP ICU, Mallinckrodt HiLo, Portex Profile Soft Seal, Rüsch Super Safety Clear and Sheridan CF. Fifty patients undergoing endotracheal intubation with a cuffed tube of internal diameter 7.0 mm were studied. Tracheas were intubated using one of the endotracheal tubes in random order. Cuff pressure to prevent air leakage at standardized ventilator setting (peak inspiratory pressure 20 cmH2O/PEEP 5 cmH2O/respiratory rate 15 breaths min(-1)) was assessed by auscultation of audible sounds at the mouth. Patients characteristics and cuff pressures from each brand were compared to the Microcuff group using the Mann-Whitney U-test (P < 0.05 was chosen as the level of statistical significance).

Patients' median age (range) was 14.2 (12.0-17.1) yr, body weight 57.5 (40.0-81.9) kg and length 164.9 (146.5-190.0) cm. No significant differences in patients' characteristics were found between groups. Mean cuff pressure (all tubes) required for air sealing was 19.1 (8-42) cmH2O. The Microcuff tube required significantly lower sealing pressures (9.5 (8-12) cmH2O) compared to the other brands of endotracheal tube (P < 0.05, Mann-Whitney U-test).

The Microcuff endotracheal tube with its ultra-thin polyurethane cuff membrane required the lowest sealing pressure to prevent air leakage. These features are potentially of interest for long-term intubated patients and for cuffed endotracheal tubes in children, allowing tracheal sealing at lower cuff pressures implying less damage to the trachea.