摘要 |
A method for providing a pressure reference level for pressure triggering a ventilator responsive to a spontaneous breathing attempt by a patient. In the method, the patient connection of the breathing circuit is capped or plugged. A gas flow is then provided through the breathing circuit and is altered to an amount that causes the flow resistance properties of the breathing circuit to generate a desired gas pressure in the breathing circuit suitable for use as a reference pressure by the ventilator for pressure responsive triggering. During the operation of the ventilator, gas flow in a corresponding amount serves as a bias flow in the breathing circuit to assist breathing by the patient. The bias flow also generates the reference pressure level in the breathing circuit. A reduction in pressure from the pressure level resulting from inhalation by the patient triggers the operation of the ventilator.
|