Table of Contents
Advertisement
P
O
RODUCT
VERVIEW
The Rise Time settings should be reassessed and adjusted after the patient is placed on the
ventilator and initially stabilized. To minimize patient's work of breathing and potential for
pressure overshoots, operators must take the following into consideration when setting the
Rise Time:
The Rise Time for a passive lung is driven primarily by airway resistance, and is fairly
independent of compliance.
An adult patient with high Resistance may benefit from a Rise Time setting of 3 to 4 for
optimal breath delivery. Rise Times of 8-10 are optimized for infants and are flow limited.
(The infant circuit is not intended for flows > 60 LPM.)
Cycle Off% -- the unit allows the operator to adjust the Cycle Off%. The primary purpose
of this parameter is to set a fraction of peak flow at which inspiration ends and exhalation
begins. A key application for Cycle Off% is to adjust for leaks present in and around the
patient circuit or the patient themselves.
Note:
Note:
Mode -- Pressing the MODE button will highlight the current ventilation mode. Pressing the
7.
Parameter button again will allow for the selection of volume or pressure targeting which is
shown as either "(V)" for volume or "(P)" for pressure. Selecting volume assures a constant
volume is delivered to the patient in the inspiratory time using a constant flow. Pressure
targeting ventilation provides a constant airway pressure for the duration of the inspiratory
time using a decelerating flow pattern. See "Additional Modes of Operation" for a
2-12
Patient's respiratory pattern
•
Patient's comfort
•
Patient's flow demand
•
Resistance (Mechanical/Physiological)
•
Compliance characteristics
•
Resistance
5
20
50
200
The longest duration of a spontaneous pressure supported breath is limited to 5
seconds. At the end of this time, the ventilator ends flow and opens the exhalation
valve. (All other breaths are time cycled.)
Cycle Off% is principally made available as a parameter for NPPV mode, where a
•
much higher setting is required to cycle the breath properly in the presence of a
leak. If a higher value is not used and there is a leak, the tendency will be for the
system to time cycle at 5 seconds instead of flow cycle. This is due to the fact that
the leak flow might be higher than 25% of the peak flow, so the cycle threshold is
never crossed.
If there is no leak, increasing the Cycle Off% will cause breaths to cycle sooner,
•
thus delivering less volume. If it is set too high, the breath will end early relative to
patient effort and may lead to the triggering of a second breath.
Clinicians must carefully assess the patient's response to the Cycle Off%
application and must carefully adjust the flow cycle setting to optimize patient
ventilatory support and comfort.
www.zoll.com
Rise Time
1
3
5
10
906-0731-01 Rev. J
Advertisement
Table of Contents
