Two centre double blind randomised controlled trial comparing IM diamorphine with pethidine for analgesia in labour 2009-2012
Investigators: M Wee, J, Tuckey, D, Bick, P,Thomas, J, Alexander, R, Sawdry
Project Funding: NIHR Research for Patient Benefit programme
Intramuscular pethidine is routinely used in the UK for analgesia in labour. However, studies suggest that its mode of action is primarily as a sedative. It causes a number of side effects in both mother and neonate such as nausea and dysphoria during labour and crosses the placenta resulting in reduced fetal heart rate variability. It can cause respiratory depression and impaired breast feeding in the neonate. There are few adequately powered studies comparing the relative side effects and efficacy of different opioids in labour. Systematic reviews comparing parenteral opioids in labour have suggested the need for well designed and suitably-sized trials comparing pethidine with other opioids. Preliminary studies indicate that diamorphine may be a better analgesic with fewer side effects.