[Control of respiration by inspiratory pressure support]

A reduction in arterial PCO2 is an important cause of respiratory muscle inhibition during pressure support (PS). A nonchemical inhibition of respiratory activity during PS has also been demonstrated. This nonchemical inhibition of inspiratory activity is not observed with all modes of mechanical ventilation. In fact, the higher is the initial flow rate provided by the ventilator, the more efficient the nonchemical inhibition of respiratory activity. Currently, PS is the ventilatory support technique which provides the highest initial inspiratory flow. However, these new physiological findings should facilitate the development of more effective ventilatory support techniques.