Using the Z Vent Ventilator
9650-002360-01 Rev. A
ZOLL Z Vent Ventilator Operator’s Guide
4-15
Vt Parameter Window Options
The Vt parameter defines the volume (ml) delivered to the lung with each breath. Tidal volume
is calculated by integrating the flow over the inspiratory time. During volume targeted
breathing, pressing the Vt parameter button highlights the currently set tidal volume and
enables it to be changed. When breathing is pressure targeted, the delivered tidal volume is
shown as outlined text and is based on the PIP and patient’s pulmonary mechanics.
Warning!
In CPAP and BL, a Vt that is lower than anticipated may be an indication that the
patient is not able to adequately ventilate.
Note:
In CPAP, the V
t
delivered and V
min
may be overestimates of the true volume going to
the patient when leaks are present. The O
2
Use values accurately display the O
2
use,
though the amount used is more than if no leak was present.
Warning!
If significant leaks are present during CPAP and BL modes, the V
t
delivered and V
min
shown may be overestimates of what is actually being delivered to the patient. The
adequacy of ventilation should be assessed using an alternate method.
Secondary Parameters and Alarm Thresholds/Limits
The secondary parameters for the Vt parameter window are the following:
•
Vt High Limit (lower number below the alarm bell)
•
Vt Low Limit (number below the Vt High Limit)
Note:
The high/low Vt alarm limits are not presented during volume targeted ventilation
because the ventilator automatically alarms if 2 consecutive breathes are out of range.
The high Vt alarm can be set off, or it can be set from 50 to 2000 (ml). The low Vt alarm can be
set off, or it can be set from 5 to 500 (ml).
The Vt High Limit setting cannot be adjusted below the Vt setting or the Vt Low Limit setting
and attempting to do so generates a conflict popup message.
The Vt High Limit setting is used to limit the delivered tidal volume Pressure Targeted breaths.
If two consecutive breaths are limited by this setting, the High Tidal Volume alarm (2072) is
triggered.
The Vt Low Limit setting is used to trigger the Low Tidal Volume alarm (2073).
Warning!
During pressure targeted breathing with infant and pediatric patients, always set the
high tidal volume limit just above the desired tidal volume. Doing this ensures an alarm
in the event of a leak or decanulation.
To change an alarm threshold setting, follow these steps:
1. Press the Vt parameter button more than once until desired alarm threshold highlights.
2.
Turn the
Dial
until the desired value is reached.
3.
Press the
Accept
button to enable the change.
