EBME Forums Forums Management Medical Equipment Management entonox scavenging

Hi Guys,
I hope you are well. I have been asked to look into scavenging (AGSS) in our delivery suite to investigate staff exposure risks. We currently use therapy comfort demands valves. These have the exhalation outlet connected vis tubing to the AGSS via the MEC receiving system. The issues we are having is that many patients do not like them as a.....they make a noise! and b....they seem heavy with this tubing connected. Also, patients have a tendency to breath it in, then scream it out into the room. Any info at all on how other trusts are managing this will be greatly appreciated, thank you in advance for any input you can offer

Surely the amount of exhaled Entonox per patient (expectant mother) is going to be minuscule. This sounds to me like a (yet another) case of trying to solve a "problem" that doesn't actually exist. In my opinion normal (or even, natural) ventilation of the room shall suffice.

Further clues:- when used as originally intended (that is, with anaesthesia machines in operating theatres) AGSS removes exhaled gases from a continuous (and often prolonged) system. On the other hand, when used it Delivery Suites et al, Entonox in only given in response to patient demand (demand valve) and (normally, at least) should not be either prolonged or excessive; otherwise we end up with a new mother too dozy to respond to encouragement.

If unconvinced, it would be interesting to take an analysis of the room air when all this drama is taking place; how many parts per million etc. of this and that gas.

Thanks Geoff, i agree but i have been asked to help. The H&S manager has asked. There have been reports (and therefore local backlash) over waste entonox causing B12 deficiencies . i was just asking what other trusts do in these areas

Hi Carl,

We recently went through the same process during a refurb of our maternity unit - we replaced our old Penlon AGSS units with the MEC version and have to say they are considerably more noisy.

We've got the BPR Ultraflow system and but haven't had any complaints/feedback.

Not much help but at least you know it's not just you suffering the noise issue - next thing you know they'll be some dikat stating that in-room ear defenders are required due to exposure to the noise...

Yes, I see your problem, Carl. The buck has been passed. Presumably it's the N2O in the N2O/O2 mix that is giving cause for concern

Within a matter of seconds I found a few references on line regarding the possibility of N2O causing B12 deficiency. Also many mention that this condition is generally easily remedied by diet or vitamin supplements. This one appears to be comparatively recent (and useful). May I presume that your H&S Manager also has access to the internet?

I am wondering if it's exposure of Entonox to staff that may be the real issue here: midwives et al. It will be used in other areas apart from the Delivery Suite, of course: Fracture Clinics, Plaster Rooms, etc., etc.

I seem to recall that N20 itself is heavier than air, and sinks to floor level (where it presents a hazard to mice etc.). I'm not so sure about Entonox, but we should not assume that it disperses freely (or randomly) in room air. It would be nice if HVAC designs included exhaust vents at low level in all surgical rooms, or any other room where medical gases are used.

Lastly, to my (old-fashioned) mind, it is the fact that your patients don't like the present set-up that should provide the impetus for (simple, I would have thought) changes in approach.

There is cause for concern. Certainly when management try and cover things up......
https://www.bbc.co.uk/news/uk-england-essex-64216867
You cannot dismiss it and all respect should be given to those being around it daily.
BPR have a system that destroys it and is very clever, the chances of NHS spending money on it though???

I would rate the chances as very high: BPR.

N2O to N2 and O2 sounds good to me.

Meanwhile, I should imagine that Professor Sir Colin Berry enjoyed your post!