From Euroanesthesia 2016 – Room Auditorium 1, 08:30-09:15 Sunday 29 May
In this session, Dr Philipp Lirk, University of Amsterdam, Netherlands, will attempt to unravel the myths and facts behind one of anaesthesia’s oldest acquaintances – nitrous oxide.
“Nitrous oxide was discovered in the 18thcentury and is therefore one of the oldest drugs in continued use today,” explains Dr Lirk. “For a long time it has been known that its three main actions are sedation, analgesia and euphoria. Nevertheless, the precise mode of action, and clinical consequences of its use are only now beginning to be understood.”
On the positive side, nitrous oxide facilitates the induction and emergence of anaesthesia using volatile anaesthetics, acts as an intraoperative analgesic, and some claim it has the potential to reduce chronic pain via an NMDA-dependent mechanism. After seeing the use of nitrous oxide decline over the decades, its use as a sedative for mild to moderately painful procedures has been reappraised.
On the negative side, nitrous oxide interferes with vitamin B12 metabolism and methionine synthase, potentially causing haematological and neurological adverse effects. It dose-dependently increases the likelihood of postoperative nausea and vomiting, and diffuses rapidly into air-filled cavities such as tube cuffs or a closed off middle ear. Lastly, it has been alleged to decrease fertility and to be teratogenic but this has never been corroborated by scientific evidence.
“Most recently, nitrous oxide has been demonstrated to alleviate symptoms of refractory depression, and may now be entering a new life in psychiatry,” says Dr Lirk. “The current lecture will focus on some of the myths surrounding this ancient drug, review evidence from large-scale trials on the safety and benefits of its use, analyse indications and contraindications for its use, and look at how you can still get the nitrous oxide effect even if your hospital has decided to stop providing nitrous oxide.”
More information on http://euroanaesthesia2016.esahq.org