Posted By garry saunders Any details of passive inhalation risks from the use of entonox in midwifery and obstetric practice. If so can I have details and sources for referrences where possible/known.

Posted By Alison Dando Rat experiments are associated with exposure to 1000 ppm and above for 8 hours or more a day and I have known staff in some delivery suites being exposed to these levels. If you look in the HSC publication "Anaesthetic agents: Controlling exposure under COSHH" it mentions 6-7 air changes per hour for delivery suites but in our Trust we have found that this is too low. We are running at 15. The problem with analgesia as opposed to anaesthesia that you get in your face what the patient is breathing in. Mothers to be as labour is painful will not keep any mouthpiece in their mouths all the time and some get rather verbal! The extract system is attached to the mouthpiece. I have had stories related where midwives have experienced symptoms that have been put down to inhalation of entonox such as drowsiness, nausea and disorientation. As a precaution we do allow any of our pregnant midwives to deliver and pregnant obstetric medics are advised not to go into the suites although maternity theatres are more acceptable because they have scavenger ventilation systems. Delivery rooms should have active extract sytems in the rooms which should be maintained and environmental monitoring should be regularly undertaken.