Early cycling is identified on the expiratory flow–time scalar by an upward deflection at the onset of expiration, which occurs because the patient’s inspiratory effort continues after the ventilator has ended its inspiratory phase. However, in some cases, a distinct upward deflection may not be present. Instead, the waveform may show a reduced peak expiratory flow or a truncated (amputated) expiratory peak, reflecting the same continuation of patient effort into early expira

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 ti

This patient with Guillain–Barré syndrome had been on mechanical ventilation for more than five days. When transitioned to pressure support mode, the ventilator waveforms showed patient-triggered breaths, and clinically the patient appeared comfortable, without accessory muscle use or tachypnea. However, the patient’s muscle strength remained at grade 1, and in neuromuscular weakness, such low muscle power would typically result in marked work of breathing on pressure support

Rise time is the interval required for the ventilator to achieve the target pressure in pressure control or pressure support modes. It is also referred to as the pressurization rate, and it directly influences the peak inspiratory flow delivered to the patient. When the rise time is set too slow, the pressure increases gradually rather than promptly. This can be uncomfortable for patients who are breathing rapidly or have strong inspiratory drive, because the ventilator flow

The flow trigger settings on Maquet ventilators function differently from those on most other ventilators. On Maquet devices, the trigger sensitivity is set on a scale from 1 to 10, where: 1 represents the least  sensitive trigger, meaning the patient must generate more effort to initiate a breath. 10 represents the most  sensitive trigger, requiring minimal patient effort to trigger ventilation. This is opposite to the convention used in many other ventilators, where higher

A pressure spike at the end of inspiration is sometimes misinterpreted as delayed (late) cycling. However, it is important to recognize that a similar spike can occur simply due to relaxation of the inspiratory muscles, even without active expiratory effort. When a strong inspiratory effort suddenly stops, the ventilator may not immediately compensate, leading to a brief overshoot in airway pressure. Thus, not all end-inspiratory pressure spikes indicate late cycling; some ma