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.
Single-blind, randomized controlled animal study using a previously validated live porcine model of accelerated intubation-related tracheal injury.
Animal research facility.
Ten piglets (weight, 16-20 kg each) were anesthetized and underwent intubation using a cuffed ETT.
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.
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).
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.