GE iVent 201 1.4, Руководство пользователя

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Appendix D: Theory of Breath Delivery
213
BREATH DELIVERY
The iVent
TM
201 is a positive pressure mechanical ventilator that delivers air or
air/oxygen mixture to the patient’s lungs under positive pressure. Each breathing
cycle consists of two phases as described below (Figure 164).
Figure 164: Pressure Breath Cycle
1. An inspiratory phase, in which gas is delivered to the patient’s lungs and
airway pressure increases. At the end of the inspiratory phase, the
ventilator stops delivering flow and allows the patient to exhale.
2. An exhalation phase, in which air flows out from the patient’s lungs and
pressure returns to the baseline pressure. The baseline pressure may be
either the ambient pressure - curve 1, or a higher positive end-expiratory
pressure (PEEP) - curve 2.
The ventilator’s control system accomplishes the ventilation cycle by a
mechanism which:

Initiates inspiration

Controls the flow or pressure during the inspiration phase

Ends inspiration or begins exhalation (termination)
PATIENT TRIGGERING
A patient may trigger a breath by creating an inspiratory effort detected by the
ventilator. The iVent
TM
201 has three operator selectable methods for triggering
breaths as illustrated below: