Ergometrine stability in postpartum haemorrhage kits: Does temperature and light matter?

Background Postpartum haemorrhage (PPH) kits containing uterotonics are used on obstetric units for the timely management of PPH. Visible discolouration of ergometrine and ergometrine‐oxytocin injections was observed in PPH kits stored in medical refrigerators on the obstetric unit at our hospital. Aim To investigate the stability of ergometrine and ergometrine‐oxytocin injections in PPH kits under simulated clinical storage conditions and to determine the potency of ampoules quarantined from PPH kits on our obstetric unit. Material and methods Ergometrine and ergometrine‐oxytocin injection ampoules were stored exposed to and protected from light at 4°C and room temperature (25°C) for up to three months, and assayed by high‐performance liquid chromatography. Stability was based on the time for the ergometrine or oxytocin concentration to fall to 90% of the original concentration (t90). The potency of quarantined discoloured ampoules also was determined. Results Ergometrine was stable at both temperatures for >6 months, when stored protected from light in simulated clinical conditions. When exposed to light, ergometrine was stable for approximately 4 days at 25°C and 10 days at 4°C. Discoloured ergometrine and ergometrine‐oxytocin injection ampoules were found to be <90% of the nominal concentration. Conclusion Stability of ergometrine in PPH kits is largely unaffected by temperature fluctuations (at 4°C and 25°C) over 6 months when protected from light. Ergometrine and ergometrine‐oxytocin ampoules should be inspected prior to use and any discoloured ampoules discarded.