Using the Z Vent Ventilator
9650-002360-01 Rev. A
ZOLL Z Vent Ventilator Operator’s Guide
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Note:
An adult patient with high resistance may benefit from a Rise Time setting of 3 to 4 for
optimal breath delivery. Rise Times of 8 to 10 are optimized for infants and are flow
limited. (The infant circuit is not intended for flows > 60 LPM.)
Cycle Off % Parameter
For flow cycled breaths, the ventilator transitions from inspiratory to expiratory phase when the
flow drops below a set percentage of the peak flow. The default is 25% of peak flow with a
range of 10 to 70% Cycle Off % is typically used during noninvasive ventilation to ensure the
breath cycles in synchrony with the patient. Some patients may have difficulty cycling due to
their lung mechanics or a bag that prevents the flow from reaching the cycle flow rate. When
this happens, spontaneous breathe may time cycle causing asynchrony.
You can adjust the Cycle Off% value to account for patient leaks and weak respiratory effort.
Users must carefully assess the patient's response when adjusting the Cycle Off % to avoid
cycle asynchrony and patient discomfort
Note:
The longest duration of a spontaneous breath is 5 seconds. At the end of this time, the
ventilator ends flow and opens the exhalation valve.
If there is no leak, increasing the Cycle Off % parameter causes breaths to cycle sooner, and
deliver less volume. If you set the Cycle Off % parameter too high, the breath ends early
relative to patient effort, which may lead to the triggering of a second breath.
Spont Ti Limit Parameter
The Spontaneous Inspiration Time (Spont Ti) Limit parameter provides an additional method to
limit the duration of spontaneous breaths in the presence of a leak or weak respiratory effort.
The parameter provides an inspiratory time limit for spontaneous breaths.
Adult default is 3.00 sec, Pediatric default is 2.00 sec, and Mask CPAP default is 3.00 sec.
