PIEB vs CEI for Labor Analgesia: An MLAC Study

Study Overview
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Brief Summary
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Utilizing a 'minimal local analgesic concentration (MLAC) study' design to first determine the relative potency of Programmed Intermittent Epidural Bolus (PIEB) compared to Continuous Epidural Infusion (CEI) and secondly to determine the mechanism to explain the potential PIEB efficacy advantage.

Detailed Description
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Pregnant women who present to Labor and Delivery for an anticipated vaginal delivery will be identified as potential participants based on inclusion/exclusion criteria and their desire for labor epidural analgesia. Once identified, interested candidates will be fully informed of the study procedures, have all questions answered, and informed consent obtained. Pregnant participants will receive a labor epidural upon the patient's request and dosed per protocol to adequate analgesic level. Patients will be randomized into 1 of 4 groups. Either group I or II in Study Part A and group III or IV in Study Part B in a double-blinded design. Each study part will run in parallel and independently. Each group will have a varying concentration of bupivicaine infusion; continuous or intermittent bolus administration. In addition each group will have continuous or intermittent bolus administration of sufentanil. These concentrations and forms of administration will be blinded to both the patient and study administrator. Each epidural infusion concentration and continuous or bolus administration will be determined to be a success or failure based on analgesic scores. The investigators' primary outcome will be the minimal local anesthetic concentration of the final participants in each respective group upon study completion. DATA SAFETY MONITORING PLAN will follow standard of clinical care. Any adverse events will be reported to the PI and necessary adjustments to the protocol will be immediately instituted.

Official Title
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Programmed Intermittent Epidural Bolus (PIEB) Compared to Continuous Epidural Infusion (CEI) Relative Efficacy and Mechanism of Efficacy For Labor Anlagesia: A Minimal Local Analgesic Concentration (MLAC) Study

Conditions
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Pregnancy

Intervention / Treatment
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* Drug: Bupivacaine
* Drug: Sufentanil


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ASA I & II, Nulliparous and Multiparous, Spontaneous/Induced/Augmented Labor, Early active labor (cervix <5 cm (if known)), Pain (VPS) > 3, 18-45 years of age Exclusion Criteria: <37 weeks gestation, H/o Cesarean Section, Multiple Gestation, Pre-eclampsia, Narcotics within 3 hours prior to labor epidural placement, Chronic Pain (as defined by chronic opiate consumption), Women who are participating in another study that will impact protocol

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Part A Group 1<br>CEI bupivacaine and CEI sufentanil | Drug: Bupivacaine<br>* Continuous or bolus administration<br>* Other names: marcaine;Drug: Sufentanil<br>* Continuous or bolus administration<br>* Other names: sufenta;|
| Active Comparator: Part A Group 2<br>PIEB bupivacaine and PIEB sufentanil | Drug: Bupivacaine<br>* Continuous or bolus administration<br>* Other names: marcaine;Drug: Sufentanil<br>* Continuous or bolus administration<br>* Other names: sufenta;|
| Active Comparator: Part B Group 3<br>CEI bupivacaine and PIEB sufentanil | Drug: Bupivacaine<br>* Continuous or bolus administration<br>* Other names: marcaine;Drug: Sufentanil<br>* Continuous or bolus administration<br>* Other names: sufenta;|
| Active Comparator: Part B Group 4<br>PIEB bupivacaine and CEI sufentanil | Drug: Bupivacaine<br>* Continuous or bolus administration<br>* Other names: marcaine;Drug: Sufentanil<br>* Continuous or bolus administration<br>* Other names: sufenta;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Minimum Local Analgesic Concentration (MLAC) of the Final Participants in Each Respective Group at Study Completion | The mean concentration of Bupivacaine in patients who have success or failure outcome were compared between groups. | From initial epidural bolus to delivery (up to approximately 16 hours) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time to First Clinician Rescue Analgesia Request (From Initial Epidural Dose) | The time to first clinician rescue analgesia request in patients who have success or failure outcome were compared between groups. | From initial epidural bolus to delivery (up to 16 hours following initial bolus) | 
| Numerical Verbal Pain Scores | The initial pain score (VAS 0-10 scale with 0 means no pain and 10 means max pain) in patients who have success or failure outcome were compared between groups. | Patients were assessed once between initial epidural bolus to delivery (up to 16 hours following initial bolus) | 
| Patient Satisfaction With Labor Analgesia | 0-100% (0 means least satisfaction and 100 means most satisfaction) | Participants were assessed once from initial epidural bolus to delivery (up to approximately 16 hours) | 
| Labor Outcome (Spontaneous, Assisted, Cesarean) | Labor outcome in patients who have success or failure outcome were compared between groups. | At the time of delivery | 
| Number of Participants Requiring Treatment for Pruritus, Nausea and Vomiting, or Hypotension | Number of Participants Requiring Treatment for pruritus, nausea and vomiting, and hypotension were reported. | From initial epidural bolus to delivery (up to 16 hours following initial bolus) | 
| Number of Participants With Maternal Nausea/Vomiting | yes/no. | From initial epidural bolus to delivery (up to 16 hours following initial bolus) | 
| Protocol Success or Failure | Success - No supplemental analgesia request until vaginal exam c/w 8 cm dilation or more -> 0.01% w/v reduction in subsequent participant's local anesthetic. Failure - Supplemental analgesia request c vaginal exam c/w less than 8 cm dilatation ->0.01% w/v increase in subsequent LA infusion. | From initial epidural bolus to delivery (up to 16 hours following initial bolus) |