Development of Variable Volume Automated Mandatory Boluses for Patient-controlled Epidural Analgesia During Labour (VVAMB)

KK Women's and Children's Hospital

Status and phase: Enrolling; Phase 3

Conditions: Labor Pain; Breakthrough Pain

Treatments: Drug: Fentanyl; Device: Epidural infusion pump; Drug: Ropivacaine

Study type: Interventional

Funder types: Other

Identifiers

NCT04011150

AM/CT001/2018

Details and patient eligibility

About

A novel epidural delivery regimen was developed: Variable volume automated mandatory bolus (AMB) (VVAMB) will advance individualisation of labour epidural analgesia, by which a larger volume of bolus may contribute to better spread of the local anaesthetics within brief period and thereby reduces the chances of motor blockade that could reduce instrumental deliveries.

Full description

Epidural analgesia is the gold standard of pain relief for labour pain. Despite this, up to 50% of parturients continue to experience pain leading to suffering and increased caregiver workload. There is also higher risk of motor blockade found in those receiving epidural analgesia, and these factors is associated with dysfunctional labour requiring obstetric intervention (instrumental delivery). Automated mandatory bolus (AMB) of variable-frequency (VAMB) has been shown to provide better pain relief as compared with conventional patient-controlled epidural analgesia (PCEA) with basal infusion, however its long lockout time per hour is associated with unsuccessful patient bolus requests, with similar motor block to conventional regimens.

The investigators therefore proposes to develop a novel epidural delivery regimen: Variable volume AMB (VVAMB) will advance individualisation of labour epidural analgesia, by which a larger volume of bolus may contribute to better spread of the local anaesthetics within brief period and thereby reduces the chances of motor blockade that could reduce instrumental deliveries. This algorithm development including pilot and clinical trial will compare VVAMB with VAMB regimens, in reducing the incidence of motor block in 216 term women requesting for labour epidural analgesia.

Enrollment: 216 estimated patients

Sex: Female

Ages: 21 to 50 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Healthy (American Society of Anesthesiologists (ASA) physical status 1 and 2) primiparous parturient at term (≥36 weeks gestation);
• Singleton fetus;
• In early labor stage (cervical dilation ≤5cm);
• Request labor epidural analgesia and able to administer combined spinal epidural analgesia (CSEA) according to protocol.

Exclusion criteria

• Non-cephalic fetal presentation;
• Obstetric (e.g. pre-eclampsia, premature rupture of amniotic membranes for more than 48 hours, gestational diabetes on insulin, pregnancy-induced hypertension on medication) and uncontrolled medical (e.g. cardiac disease) complications;
• Have contraindications to neuraxial blockade or have received parenteral opioids within last 2 hours;
• Dural puncture/ suspected dural puncture at initiation of CSEA.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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216 participants in 2 patient groups

Variable volume Automated Mandatory Bolus (VVAMB)

Experimental group

Description:

The anaesthetic drug and pain medication are prepared in an epidural infusion pump with the VVAMB programme. The programme uses higher doses with lower frequency of medication (ropivacaine and fentanyl), and a patient control button for the patient to control the additional pain relief demands depending on the requirements during labour.

Treatment:

Drug: Ropivacaine

Device: Epidural infusion pump

Drug: Fentanyl

Automated mandatory bolus (AMB) of variable-frequency (VAMB)

Active Comparator group

Description:

The anaesthetic drug and pain medication are prepared in an epidural infusion pump with the VAMB programme. The programme uses lower doses with more frequency of medication (ropivacaine and fentanyl), and a patient control button for the patient to control the additional pain relief demands depending on the requirements during labour.

Treatment:

Drug: Ropivacaine

Device: Epidural infusion pump

Drug: Fentanyl