In pressure support mode, early cycling dyssynchrony can be recognized on the flow–time scalar by an upward deflection at the start of expiration. This indicates that the patient’s neural inspiratory effort continues even after the ventilator has ended the mechanical inspiration. The dyssynchrony can be corrected by reducing the flow termination criterion (expiratory trigger sensitivity) to a lower percentage, thereby prolonging the inspiratory phase and better matching it wi

Flow adaptation is a term used by some ventilator manufacturers to describe the delivery of additional flow during volume control ventilation in response to strong patient inspiratory efforts. In this example, a downward deviation of the airway pressure waveform during the first half of inspiration indicates the patient’s vigorous inspiratory effort. The ventilator senses this increased demand and provides supplemental flow, producing a small upward bump above the otherwise c

Flow starvation is a type of patient–ventilator dyssynchrony that occurs when the ventilator’s flow delivery fails to meet the patient’s inspiratory demand, resulting in a scooped appearance of the inspiratory pressure–time waveform. The term “work shifting” is now preferred, as it more accurately describes the phenomenon in which part of the inspiratory workload shifts from the ventilator to the patient. This can be recognized by a downward deformation of the inspiratory air

The following example shows a flow–time scalar with two distinct peaks. The initial peak corresponds to the patient’s inspiratory effort, followed by a rapid return of flow to baseline as the inspiratory effort ends and/or expiratory muscle contraction occurs. Subsequently, a stepwise increase in flow appears as the ventilator delivers additional flow to compensate for a leak. A second flow peak is then observed, representing a new patient inspiratory effort. The presence of

Early cycling and early trigger can produce similar waveform patterns during the expiratory phase, making them challenging to distinguish. The following example highlights the key differences between the two. In early cycling, the breath is initiated by the patient, but the neural inspiratory effort continues beyond the ventilator’s inspiratory phase, resulting in an upward deflection in the expiratory flow–time scalar. In contrast, during early trigger, the breath is initiat

An upward deflection in the expiratory flow–time scalar, accompanied by deformation of the plateau phase in a machine-triggered breath during volume control ventilation, should raise clinical suspicion for reverse triggering