Control of tracheal cuff pressure: a pilot study using a pneumatic device

Abstract

Objective: To evaluate the efficacy of a simple mechanical device to maintain constant endotracheal cuff pressure (Pcuff) during mechanical ventilation (large encased inflatable cuff connected to the endotracheal cuff and receiving constant pressure from a heavy mass attached to an articulated arm).

Design and setting: Single-center, prospective, randomized, crossover, pilot study in a medical intensive care unit.

Patients and participants: Nine consecutive mechanically ventilated patients (age 62+/-20 years, SAPS II score 39+/-15).

Interventions: Control day: Pcuff monitored and adjusted with a manometer (Hi-Lo, Tyco Healthcare) according to current recommendations (twice a day and after each intervention on the tracheal tube); initial target Pcuff 22-28 cmH20. Prototype day: test device connected to the endotracheal cuff; same initial target. Continuous Pcuff recording during both days. Control and prototype days in random order.

Results: Pcuff values over 50 cmH20 were recorded in six patients during the control day (178+/-159min), never during the prototype day. During the control day, Pcuff was between 30 and 50 cmH20 for 29+/-25% of the time, vs 0.3+/-0.3% during the prototype day (p<0.01). Pcuff was between 15 and 30 cmH20 for 56+/-36% of the time during the control day, vs 95+/-14% during the prototype day p<0.01). During the control day, Pcuff was below 15 cmH20 for 15+/-17% of the time, vs 4.7+/-15% during the prototype day (p<0.05).

Conclusions: The tested device successfully controlled Pcuff with minimal human resource consumption. Prospective studies are required to assess its clinical impact.