role of I E ratio in HFOV

[vrpatilisl]

hi all 

Can anybody please explain to me the role of I:E ratio if high oscillatory ventilation.

and also  what is PEEP in HFOV?

 

thanks

 

[yangw126]

In HFOV , the  parameters  setting  does not include  I:E，or  PEEP

[vrpatilisl]

 hi i know PEEP not there insetting just asking .but IE ration radio buttonnthere in SLE 6000.

[Akash Sharma]

Dear sir

Normally one starts off with I:E ratio of 1:2 or in some ventilators represented as a percentage like 33%.what it means is if you have selected a frequency of 10Hz( resp rate of 600) then total Ti for a single breath would be 0.03 seconds. Remember that this IE is for each oscillation and not for recruiting breaths (that has a separate entry parameter) 

This conventional 1:2 comes from the expiratory time constant which is twice as long as inspiratory. 

For a given MAP if i am able to manage oxygenation i would not touch on the IE ratio.if you feel that you are not able to maintain oxygenation for a give MAP, in order to recruit more alveolar units one may consider increasing IE to 1:1. But  this might result in issues with ventilation also. It is always better to recruit with titrating MAP rather than I:E

Regards 

[RMM]

This is an extract from Prof Jane Pillow's book on HFOV and its applications:

You can access the entire publication free of charge from this website - https://www.draeger.com/Library/Content/hfov-bk-9102693-en.pdf - most definitely worth reading!

I hope that is helpful!

Kind regards

 

 

[M C Fadous Khalife]

You can't think about I/E and PEEP, it's a completely different ventilation principle 

WNHS.NEO.VentilationHighFrequencyOscillatoryVentilationHFOV.pdf

[vrpatilisl]

Thanks everybody for reply.i read all links and then reply

[vrpatilisl]

Hi everybody.

I want to ask for dr akash sharma sir.

As in HFO there is active expiration how ventilation manage to keep 1:2  (2 here is time of expiration). Hope you understand my question.

[Rola alzir]

Like to reactivate this question as it is really from our daily practice .. so like to read more about it . What I can share from our practice 

To change ration 1:2 to be 1:1 is when I have a baby washing CO2, badly with highest frequency possible ( 15), and lowest amplitude with which wiggles can still be evident( we use no less than 15) , so here 1:1 is my next step, in order to limit the CO2 washing , as well help oxygenation, but consider that the case is not already with hyperinflated lungs 🫁, as 1:1 can worsen this part . Again physiology and ogysiodynamics of this depends on the absolute tidal volume delivered.. 

[Neon]

simply, changing IE ratio from 1:2 to 1:1 will increase the tidal volume and cause more CO2 wash

PEEP is the MAP in HFV