Hamilton G5 - Initial Breaths: How ASV Starts; Anatomy of the ASV Target Graphics Window

624074/07 C-21
Once the optimal rate is determined, the target Vt is calculated
as:
Vt = target MinVol / optimal rate (4)
In the example of the 70 kg patient, the target Vt becomes
467 ml (see Section C.4 for details).
Figure C-9 shows the position of the target breathing pattern
as well as the safety limits imposed by the lung-protective rules
strategy.
Figure C-9. Anatomy of the ASV target graphics window.
The rectangle shows the safety limits; the circle shows the tar-
get breath pattern.
C.3.4.1 Initial breaths: How ASV starts
How does the operator make this determination: how to
achieve the target values in a given patient if it is not known
whether or not the patient can breathe spontaneously? For this
purpose, ASV uses a synchronized intermittent mandatory
pressure ventilation mode.
Each breath triggered by the patient is pressure-supported and
flow-cycled, or, the transition to exhalation is made based on
flow. In contrast, if the patient does not trigger the breath, the
delivery of the breath is pressure-preset and time-cycled.