« "Breathing" in labour | Main | Optimal foetal positioning? »

Remifentanil

I have been reading recently of a new drug that is being trialed for relieving pain in labour. Remifentanil is a member of the opiate family, delivered intravenously, via patient controlled analgesia, It is most commonly used during induction of a general anaesthetic, has a rapid onset, a short duration of action, and a half life of around 3 minutes.

Despite its rapid transfer to the patient, it is expected to have little effect on the fetus because of its rapid metabolism. When administered as a continuous infusion, remifentanil crosses the placenta rapidly and is quickly metabolised and redistributed in the fetus. With bolus doses, there were no reports of associated increases in respiratory depression in the newborn or lower Apgar scores.

It was initially used for women for whom an epidural was contraindicated and this led to the PCA method of delivery. Women learn to anticipate a contraction and “top up” their own dosage in preparation for the anticipated pain.

There are no controlled studies regarding the use of remifentanil in labour and it is again a classic case of bringing in a treatment with no prior investigations,. No-one knows if it is safe for the unborn or newborn baby or its effects on the woman in labour. It has been pointed out that remifentanil is not approved for obstetric use, but it is still being promoted, however, for use when an epidural is contraindicated.

Watch out for this one - doctors love a new “toy” top play with and women can be easily convinced to try it, even if not approved or shown to be safe, if they think they will not be able to manage the pain of labour without drugs of some kind. It will be interesting to see if it takes off and who decides to use it. Where there is money to be made, sales will be pushed and the health and well being of women and babies often takes a back seat.

Posted by andrea at April 23, 2004 05:49 PM

Post a comment