Identification of Late (delayed) Cycling

Suspect late cycling in pressure control mode when a brief negative flow appears during the latter part of the inspiratory phase accompanied by a pressure spike. Although subtle on the pressure-time scalar, careful inspection reveals a pressure rise in mid-inspiration, corresponding to the onset of expiratory muscle activity. Late cycling occurs when the set inspiratory time exceeds the patient's neural inspiratory time. To correct this dyssynchrony, the inspiratory time should be reduced to better align with the patient's neural timing. In this example, the initial I:E ratio of 1:2 was gradually adjusted to 1:5, effectively shortening the inspiratory time until the late cycling resolved.