In this pressure support mode, all breaths are patient-triggered. During the expiratory phase (in the first breath), an upward deflection appears on the flow-time scalar, indicating that the patient's inspiratory effort persists beyond the end of mechanical inflation - suggesting early cycling. When this ongoing effort is strong enough (remaining breaths), it can trigger another breath during exhalation, resulting in a double trigger. This dyssynchrony can be corrected by pro

In a patient-triggered breath, if the time lag between the onset of pressure drop and the initiation of ventilator flow exceeds 100 milliseconds, it is identified as late or delayed trigger. This delay increases the patient's work of breathing.

The following waveforms display volume control ventilation with a descending ramp pattern of inspiratory flow. All breaths are patient-triggered, as indicated by a pressure drop preceding inspiration. The pressure-time scalar shows a downward deflection below baseline, reflecting strong inspiratory efforts that generate negative intrathoracic pressure. This pattern suggests work shifting, where a significant portion of the breathing workload is transferred from the ventilator

In volume control mode, flow and tidal volume are independent variables, while pressure is a dependent variable. The peak pressure alarm serves as a safety mechanism to prevent excessive airway pressures that could cause barotrauma. When the airway pressure reaches the preset alarm limit, the ventilator terminates the inspiratory phase to avoid further pressure rise- a process known as pressure cycling.

In pressure control mode, airway pressure remains constant throughout the inspiratory phase. However, if the patient attempts to exhale before the set inspiratory time ends, the pressure transiently rises above the set inspiratory pressure. This occurs when the patient's neural inspiratory is shorter than the ventilator's set inspiratory time- a phenomenon known as late cycling. Late cycling can be recognized on ventilator waveforms by a pressure spike on the pressure-time sc

The following waveforms show a pressure spike that begins in mid-inspiration, with the pressure during latter half of the inspiratory phase rising above the initial set pressure. This occurs when the patient attempts to exhale before the set inspiratory time ends, causing an increase in intrathoracic pressure that is reflected as a pressure rise on the airway pressure waveform. This phenomenon, known as late cycling, occurs when the set inspiratory time exceeds the patient's