Automated cuff pressure modulation: a novel device to reduce endotracheal tube injury.

OBJECTIVE

To assess whether dynamically modulating endotracheal tube (ETT) cuff pressure, by decreasing it during each ventilatory cycle instead of maintaining a constant level, would reduce the extent of intubation-related laryngotracheal injury.

DESIGN

Single-blind, randomized controlled animal study using a previously validated live porcine model of accelerated intubation-related tracheal injury.

SETTING

Animal research facility.

PATIENTS

Ten piglets (weight, 16-20 kg each) were anesthetized and underwent intubation using a cuffed ETT.

INTERVENTIONS

The animals were randomized into the following 2 groups: 5 pigs had a novel device to modulate their cuff pressure from 25 cm H₂O during inspiration to 7 cm H₂O during expiration, and 5 pigs had a constant cuff pressure of 25 cm H₂O. Both groups underwent ventilation under hypoxic conditions for 4 hours.

MAIN OUTCOME MEASURE

Laryngotracheal mucosal injury after blinded histopathological assessment.

RESULTS

The modulated-pressure group showed significantly less overall laryngotracheal damage than the constant-pressure group (mean grades, 1.2 vs 2.1; P < .001). Subglottic damage and tracheal damage were significantly less severe in the modulated-pressure group (mean grades, 1.0 vs 2.2; P < .001, and 1.9 vs 3.2; P < .001, respectively). There was no significant difference in glottic or supraglottic damage between the groups (P = .06 and .27, respectively).

CONCLUSIONS

This novel device reduces the risk of subglottic and tracheal injury by modulating ETT cuff pressure in synchronization with the ventilatory cycle. This finding could have far-reaching implications for reducing the risk of airway injury in patients undergoing long-term intubation. Further clinical study of this device is warranted.