Heyer iTernIS ADV, Operator'S Manual

Page: 103 / 218

ADL/PED Operative modes | iTernIS ADV
9. 3
Volume controlled ventilation involves the delivery of a set tidal volume with each
breath. In this mode, the inspiratory pressure is not regulated and is the result of
the volume and flow, delivered by the ventilator and the completed breathing circuit
impedance (including the patient).
During this mode, the ventilator operates as a flow controller. The selected flow
wave remains unchanged, even when changing the patient’s respiratory complian-
ce or resistance. The ventilator calculates the necessary flow to meet the demands
of the set tidal volume and inspiratory time. Cycling is performed by time (determi-
ned by the configuration of the inspiratory time).
The beginning of the breathing in VCV is controlled by the respiratory rate control.
If the patient generates enough respiratory effort (greater than or equal to the con-
figured inspiratory sensitivity), the start of the inspiratory periods is determined by
these efforts, rather than by the respiratory rate. For this reason, the VCV mode is
also known as an assisted mode. The inspiratory sensitivity can be configured by
pressure or by flow.
Fig. 9-1 Image of the VCV mode main screen.
In volume-controlled mode, or tidal volume target mode, it is possible to configure
the flow waveform. You can choose between a flow wave in descending ramp
(predetermined wave) and a constant wave (rectangular). By choosing one or the
other, the ventilator adjusts automatically the calculations necessary to deliver the
selected volume (more details in the
Basic Operations chapter).
9.1 | VCV - Volume
Controlled Ventilation
9.1.2 | Flow waveform
9.1.1 |
Overview