Dräger Evita 2 dura Instructions For Use Manual page 125

Leakage compensation On
With automatic leakage compensation, Evita 2 dura delivers
550 mL on the basis of the measured leakage minute volume,
instead of the 500 mL set. 500 mL enter the lung and the
displayed inspiratory tidal volume V
450 mL measured on the expiration side is displayed without
compensation, even when leakage compensation is activated.
The minute volume measured on the expiration side is 4.5 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. Evita 2 dura must always emit an alarm if the
minute volume is too low.
With leakage compensation, the set V
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 MV
pressure P .
mean
The leakage minute volume MV
leaks into account. The sum of the minute volume MV + the
leakage minute volume MV
leak
the inspiratory minute volume delivered to the patient.
Unlimited volume compensation is inappropriate.
Evita 2 dura compensates for losses of up to 100 % of the set
tidal volume V . Due to technical tolerances, a small leakage
T
minute volume may be displayed even if the hose system is
leakproof.
is 500 mL. The volume of
T
determines the
T
is based on the mean
leak
also takes the inspiratory
leak
is consequently greater than
Description
Measurements
125