Resvent iHope RS Series, User Manual

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6-29
6. Start Ventilation
inspiration side and a minute volume of 5.0 L/min is
measured on the expiration side. The lung is ventilated
with an MV of 5.4 L/min.
Without leakage compensation, the set TV determines
the volume delivered by the ventilator.
With Leakage compensation
With automatic leakage compensation, the ventilator
delivers 660mL on the basis of the measured leakage
minute volume, instead of the 600mL set.
600mL enter the lung and the displayed inspiratory
tidal volume TV is 600mL.
The volume of 500mL measured on the expiration side
is displayed without compensation, even when leakage
compensation is activated.
The minute volume measured on the expiration side is
5.0 L/min and is also uncompensated.
If this were not so, the alarm for a low minute
volume could be inhibited by the expiratory leakage
compensation. The ventilator must always emit an
alarm if the minute volume is too low.
With leakage compensation, the set TV determines the
volume to be delivered to the patient.
This example has been simplified:
In fact, the calculated leakage correction takes into
account the pressures in the hose system.
A higher percentage volume is lost on the inspiration
side than on the expiration side because the pressure
during inspiration is higher.
The displayed leakage minute volume MVleak is based
on the mean pressure Pmean.
The leakage minute volume MVLeak also takes the
inspiratory leaks into account. The sum of the minute
volume MV + the leakage minute volume MVLeak
is consequently greater than the inspiratory minute
volume delivered to the patient.