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A Randomised Controlled Trial of Remifentanil Intravenous Patient Controlled Analgesia (PCA) Versus Intramuscular Pethidine for Pain Relief in Labour

Phase 4
Completed
Conditions
Pain Relief in Labour
Interventions
Registration Number
NCT02179294
Lead Sponsor
University of Birmingham
Brief Summary

Childbirth can be an extremely painful and the provision of pain relief during labour is a vital component of a positive maternal experience. The majority of women who deliver in modern obstetric units choose a pharmacological method of pain relief, including Entonox, the injection of opioids or epidural placement. The commonest opioid used in labour is pethidine administered by intramuscular (im) injection. The effectiveness of pain relief provided by pethidine has long been challenged. Its shortcomings are more serious when set against known side effects including maternal sedation, nausea and potential transfer across the placenta to the foetus. More than a third of women who receive pethidine subsequently require an epidural due to inadequate pain relief. Epidurals provide highly effective pain relief, but increase the risk of a forceps or suction delivery resulting in prolonged hospital stay. Therefore, there is a clear need for a safe, effective, easy to administer analgesic alternative.

Detailed Description

Patient Controlled Analgesia (PCA) comprises drug administration into an intravenous drip with a small dose given each time a woman presses a button, giving her control over her own pain relief. The pump is programmed to ensure that the maximum dose allowable is within the safe range. This form of delivery of pain relief matches the drug dose to pain sensation within the relevant time frame, which is not possible using a single dose intramuscular injection. Whilst PCA is in widespread use for acute pain relief it has only a limited role in obstetrics. The most common drug given by PCA is morphine, however, since it has a long duration of action and crosses the placenta, the potential for accumulation in the foetus and consequent neonatal sedation at delivery restricts its utility (within obstetrics) to contexts where neonatal status is not relevant, such as intra-uterine foetal death or foetal abnormality incompatible with survival.

Remifentanil is a novel synthetic opioid with a very rapid onset (blood-brain equilibration 1.2-1.4 minutes) and short duration of action (context specific half-life 3 minutes), giving it an analgesic profile which potentially makes it ideal for providing pain relief over 1-2 uterine contractions after a single intravenous dose. It is subject to rapid redistribution and metabolism by non-specific blood and tissue esterases negating the potential for accumulation in mother or foetus. Administration of remifentanil by PCA has been investigated in several small studies in comparison to pethidine and shown to provide useful, although not complete, pain relief in labour.10-12 Thus far, there is no evidence of detrimental neonatal effects in comparison to other opioids.

Recruitment & Eligibility

Status
COMPLETED
Sex
Female
Target Recruitment
401
Inclusion Criteria

Women who are admitted to labour ward who fulfil all the following criteria will be eligible to be randomised:

  • Requesting systemic opioid analgesia
  • 16 years of age or older
  • Beyond 37 weeks gestation
  • In established labour, defined as regular painful contractions, irrespective of cervical dilatation, with vaginal birth intended
  • Able to understand all information (written and oral) presented (using an interpreter if necessary)
  • Not participating in any other clinical trial of a medicinal product
  • Live, singleton pregnancy with cephalic presentation
Exclusion Criteria
  • Contraindication to epidural analgesia
  • Contraindication to intramuscular injection
  • History of a previous adverse reaction to pethidine or remifentanil
  • Patients taking long term opioid therapy including Methadone
  • Systemic pain relief opioid in the last 4 hours administered by intravenous or intramuscular injection. (Oral medications comprising opioids alone or in combination preparations, administered in this 4 hour period, are permitted).

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
PethidinePethidinePethidine is pain relief in labour
RemifentanilRemifentanilRemifentanil intravenous patient controlled analgesia
Primary Outcome Measures
NameTimeMethod
The proportion of women who receive epidural analgesia for pain relief in labour, in each group, after randomisation.At labour

The proportion of women who receive epidural analgesia for pain relief in labour, in each group, after randomization.

Secondary Outcome Measures
NameTimeMethod
• The effectiveness of pain relief provided by each technique, quantified by Visual Analogue ScalePost natally - Average of 2-3days after delivery

• The effectiveness of pain relief provided by each technique, quantified by Visual Analogue Scale

The incidence of maternal side effectsPost Natally - Average of 2-3days after delivery

The incidence of maternal side effects including

* Excessive sedation score

* Oxygen Saturation \<94% whilst breathing room air

* Nausea requiring anti-emetic administration

* Requirement and indication for supplemental oxygen

* Respiratory Depression (Respiratory rate \< 8 breaths/minute)

Delivery mode (Spontaneous, Instrumental Vaginal, Caesarean Section)Post Natally - Average of 2-3days after delivery

Delivery mode (Spontaneous, Instrumental Vaginal, Caesarean Section)

Incidence of foetal distress requiring deliveryPost Natally - Average of 2-3days after delivery

Incidence of foetal distress requiring delivery

Neonatal status at deliveryPost Natally - Average of 2-3days after delivery

Neonatal status at delivery:

* Apgar score at 5 minutes

* Incidence of foetal acidosis determined by umbilical cord gas analysis

* Requirement for neonatal resuscitation

* Incidence of and indication for admission to neonatal care

Rate of initiation of breast feeding within the first hour of birthPost Natally - 1 hour after delivery

Rate of initiation of breast feeding within the first hour of birth

Maternal satisfaction with childbirth experience determined by postpartum questionnaire prior to discharge from the delivery wardPost Natally - Average of 2-3days after delivery

Maternal satisfaction with childbirth experience determined by postpartum questionnaire prior to discharge from the delivery ward

Maternal birth experience determined by qualitative telephone interview up to six weeks postpartumUp to 6 weeks post-partum

Explore and compare women's birth experiences up to six weeks postpartum via qualitative telephone interview (Post-Natal sub-study)

Maternal perceptions of pain relief determined by qualitative telephone interview up to six weeks postpartumUp to 6 weeks post-partum

Explore and compare women's perceptions of pain relief up to six weeks postpartum via qualitative telephone interview (Post-Natal sub-study)

Infant feeding behaviours determined by qualitative telephone interview up to six weeks postpartumUp to 6 weeks post-partum

Explore and compare infant feeding behaviours up to six weeks postpartum via qualitative telephone interview (Post-Natal sub-study)

Trial Locations

Locations (1)

Birmingham Clinical Trials Unit

🇬🇧

Birmingham, West Midlands, United Kingdom

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