To avoid tracheal wall damage or inadvertent falls of the endotracheal tube cuff pressure (Pcuff) in intubated and mechanically-ventilated patients, the authors devised a simple procedure for automatic and continuous regulation of Pcuff. The procedure, only requiring a simple aquarium air pump and conventional tubing, was first tested at the bench when applied to an intubated and ventilated lung model, including an artificial trachea with an externally-variable section. The clinical performance of the procedure was tested in eight intubated patients, in whom the endotracheal tube cuff was connected to the designed Pcuff regulator during 24 h. The bench test showed that the procedure was able to maintain Pcuff constant, regardless of the changes imposed in the tracheal section. It was also effective in maintaining Pcuff during routine mechanical ventilation. Actual Pcuff recorded over the 24-h period always coincided with the target value within +/-2 cmH2O in all the patients. The procedure devised to maintain endotracheal tube cuff pressure is readily implemented, cheap, easy to operate and can be used regardless of the specific ventilator or tube used. Routine implementation of this procedure may be useful for protecting the trachea from tissue damage and for reducing the risk of ventilator-associated pneumonia.