premature cycling is caused by high trigger sensitivity or low inspiratory time
- related: basic understanding of ventilators
- tags: #permanent
- source: Murray and Nadel Ch 135 Mechanical Ventilation, Asynchrony Consequences and Management
Premature cycling is when the breath terminates before patient can have enough air. This leads to inspiratory flow by patient when the machine is in expiration phaes:
On the pressure curve, you'll see dip in pressure (patient inspiring causing more negative pressure). On the flow curve, you'll see a bump (more flow going in)
In pressure targeted mode, this is usually from having too high of trigger sensitivity (e.g. 50% of peak inspiratory flow). In flow targeted mode, this is usually from too short of inspiratory time.