This randomised controlled trial is investigating the feasibility and safety of high flow humidified nasal oxygen (HFNO) in labouring women using remifentanil for patient controlled analgesia (PCA). Opioid PCA is commonly used as pain relief for women who have contraindications to epidural analgesia such as thrombocytopaenia or who desire a non-invasive form of labour pain relief such as women undergoing vaginal birth for fetal death in utero. In our hospital, we use the opioid fentanyl, however evidence suggests that remifentanil, provides superior pain relief.
The major side effect of remifentanil PCA is maternal hypoxaemia from opioid-induced ventilatory impairment. HFNO can provide accurately titratable inspired fraction of oxygen, dynamic continuous positive airway pressure and apnoeic oxygenation. This trial is a first step towards investigating whether the addition of HFNO to remifentanil PCA is a safer option for this therapy and determine feasibility of a larger trial. If HFNO can reduce oxygen desaturation in pregnant women receiving remifentanil PCA, this could have significant application for obstetric centres worldwide, affect a shift in clinical practice and raise awareness regarding the needs of the vulnerable subpopulation of labouring women giving birth to stillborn babies.
This trial forms a component of Dr Tan’s PhD at the University of Melbourne with the research to be undertaken at The Royal Women’s Hospital.
Dr Patrick Tan, The Royal Women’s Hospital, Melbourne
The project was awarded $A14,203 funding through the ANZCA research grants program for 2023.