Fluid leakage past tracheal tube cuffs: evaluation of the new Microcuff endotracheal tube

This study compared the recently introduced Microcuff endotracheal tube HVLP ICU featuring an ultrathin (7-µm) polyurethane cuff membrane with endotracheal tubes from different manufacturers regarding fluid leakage past the tube cuff.

In vitro setup.

The following endotracheal tubes (ID 7.5 mm) were compared: Mallinckrodt HiLo, Microcuff HVLP ICU, Portex Profile Soft Seal, Rüsch Super Safety Clear, and Sheridan CF. A vertical PVC trachea model (ID 20 mm) was intubated, and cuffs were inflated to 10, 15, 20, 25, 30, and 60 cmH₂O. Colored water (5 ml) was added to the top of the cuff. The amount of leaked fluid past the tube cuff within 5, 10, and 60 min was recorded. Experiments were performed four times using two examples of each tube brand. Fluid leakage past tube cuffs occurred in all conventional endotracheal tubes at cuff pressures from 10 to 60 cmH₂O. In the Microcuff tube cuff pressure fluid leakage was observed within 10 min only at 10 cmH₂O. Results with the Microcuff tube were significantly better than all other tube brands at cuff pressures of 10–30 cmH₂O.

Within the acceptable upper limit for tracheal cuff pressure (25–30 cmH₂O) the Microcuff endotracheal tube was the only one of the tested tubes to prevent fluid leakage in our in vitro setup. In vivo studies are required to confirm these findings.