What is the definition of a patient's trigger in respiratory therapy?

In the context of respiratory therapy, a patient's trigger refers to the effort made by the patient to initiate a breath. This is fundamental in ventilatory support, particularly when using mechanical ventilation. The trigger is a signal that prompts the ventilator to deliver a breath, and it can be based on the patient's own effort, such as a specific level of pressure or flow the patient generates, or it may be time-triggered based on settings programmed into the ventilator.

Understanding the concept of the trigger is critical because it directly influences patient-ventilator synchrony, ensuring that the ventilator responds appropriately to the patient's respiratory drive. Properly set triggers can enhance comfort and effectiveness in ventilation, leading to better outcomes for the patient. In contrast, focusing on flow, volume, or resistance pertains to the mechanics of ventilation and does not specifically indicate the initiation of a breath by the patient, which is the essence of the trigger concept.