Intra-tracheal multiplexed sensing of contact pressure and perfusion.

Incorrect endotracheal tube (ETT) cuff inflation pressure causes significant problems for intubated patients. The technical development and first in vivo use of a smart ETT for measurements at the cuff-trachea interface during mechanical ventilation are described. The intra-tracheal multiplexed sensing (iTraXS) ETT contains integrated optical fibre sensors to measure contact pressure and blood perfusion. The device is tested during mechanical ventilation in a porcine model (N=6). For contact pressure, signals were obtained in all 30 measurements. For perfusion, data could be obtained in all 33 measurements. In the 3 cases where the cuff was inflated to an artificially high-level, blood occlusion is observed.