Chapter 4
4-14 Respironics V60 Ventilator User Manual 1047358 Rev N
Principles of operation
result is that the level of pressure support is controlled by the inspiratory effort
of the patient. Because the patient completely controls ventilatory output,
1
PPV may significantly improve patient-ventilator synchrony and ultimately,
patient comfort.
The PPV backup rate ensures that the patient receives a minimum number of
breaths per minute if the spontaneous breathing rate falls below the Rate
setting. If the patient fails to trigger a breath within the interval determined by
the Rate control, the ventilator triggers a Timed (backup) breath with the set
I-Time, Rise, and IPAP settings.
The control settings active in the PPV mode are shown in Figure 4-14.
Figure 4-14: PPV controls
Figure 4-15 shows PPV mode waveforms. Note how volume and pressure
increase as does the ventilatory demand of the patient. Max V (PPV maximum
volume limit) and Max P (PPV maximum pressure limit) are used to prevent the
delivery of excessive pressure or volume. More information about these limits
is provided in “About Max V and Max P alarms and alarm limits” on page 6-7.
1 Marantz, S., Patrick, W., Webster, K., et al. “Response of ventilator-dependent patients to
different levels of proportional assist.” Journal of Applied Physiology, Vol. 80: 397-403,
1996.
To Next Page
Loading...
