Hi

We have the Drager Evita 2 and 2 Dura and are experiencing regular "Flow Inop" messages. This across is all the ventilators. We have serviced the inspiratory valve.

Any one else got this problem? Or a remedy for it?

Mick

Hi
If you are using disposable exp valves I would suggest that you have some that have a harder rubber seal for the flow sensor connection. This can prevent the flow sensor from being fully engaged to the right (ie not activating the microswitch).
Draeger are aware of the issue and will exchange.

Paul

the new generation of flow sensors are slightly different in shape and size than the old ones (yellowish colour). we had similar problems with new ones but most of the time it was the switch engaging problem. Just pay a little more attention when replacing
best regards
Milan

Weve experienced this with flow sensors problems on all Drager Evita vents.
Drager have been informed of the fact.
Weve found that the contacts at the machine end need cleaning with a little contact cleaner. After this the m/c works first time with the sensor that originally failed.
Buzz the flow sensors out before you bin them, dont assume they are faulty. Or if you have a magnifier check the flow sensor wires in out to see theres no breakage.

hi to everybody


I have a prolem on evita 2 dura, FIO2 high i check on the O2 analyzer and it's really high on 21% setting i measure 33% is it the O2 mixer problem please help and if someone have a service manual it will be a big help

thank a lot
dennis

try recalibrating the O2 sensor or replacing it. It usually solves the problem.
best regards
Milan

And to add to the "knowledge base"

Following from the original post - we replaced the socket and lead, ot appears to have solved the problem and quite cheaply too.

Mick

Hi everybody

Is anyone encounter problem with EVITA 2 DURA, FIO2 high alarms, setting at 21% and it monitors 33% even you check on oxygen analyzer it really reads 33%, when you remove the Oxygen gas it will read 21%, is it the problem on O2/AIR mixer pls advice

thanks
dennis

Misaligned control knob?

Misaliged control knob - eh???

Dennis - you may have a problem with the basic calibration mechanism in the Evita. I have had this on Evita 4's and suspect that the methodology is the same for the Dura.

When the O2 cell is being calibrated there is an automatic sequence which provides air and oxygen separately, to provide a known 21% and 100% O2 calibraion point.

This is achieved by a small shuttle valve being driven across the inlet to the O2 cell and providing the requiste gas at the appropriate time. The valve seal is provided by a rubber/neoprene? disc which should eliminate any dilution of the intended calibration gas. If the disc wears then some dilution can occur and the calibration settings are assumed by the vent to have taken place as expected, however there will have been some electronic bias placed on the measuring circuit to compensate for this drift.

In your case, if oxygen is leaking round the seal when the vent assumes a 21% cal point to have been accepted, it will allow enough oxygen into the patient circuit to achieve the same O2 cell voltage, thus giving you an unexpectedly high O2 reading both on the vent and your monitor.

You can fairly easily check to see if you have this problem - assuming the Dura to be the same as the Evita - by removing the O2 cell and looking into the opening thus revealed in the calibration block. The black sealing disc in question should be visible seated neatly on a brass shaft in the centre of the opening. The wear on the seal tends to occur at the shaft when the mounting hole becomes eccentric thus allowing the seal to slip slightly to one side during calibration.

Replacement of the sealing disc is simple if a little fiddly and the results are remarkable.

Failing that I think you might be looking at replacing one of the main mixing valves - expensive!

Hope this may be of use.

Brian