Late Cycling

A step-up in airway pressure near the end of the inspiratory phase, along with a return of inspiratory flow to baseline or even a brief negative flow, indicates that the patient is activating expiratory muscles while the ventilator is still delivering inspiration. This occurs when the mechanical inspiratory time exceeds the patient’s neural inspiratory time, resulting in late (delayed) cycling dyssynchrony.

This dyssynchrony can be corrected by reducing the set inspiratory time, typically by adjusting the I:E ratio to allow an earlier transition from inspiration to expiration.