Neuraxial Versus Systemic Analgesia for Latent Phase Labor Effect on Rate of Operative Delivery

Early Compared With Late Neuraxial Analgesia in Nulliparous Labor Induction

The purpose of this study in nulliparous women undergoing induction of labor is to determine whether initiation of neuraxial analgesia compared to systemic opioid analgesia early in labor (< 4 cm cervical dilation)affects the cesarean delivery rate.

Study Overview

• Status: Completed
• Conditions: Pregnancy; Labor Pain
• Intervention / Treatment: Procedure: combined spinal epidural analgesia; Procedure: late analgesia (systemic)

Detailed Description

Women in early labor frequently request pain medication. Obstetricians may prescribe narcotics (administered as an intravenous (IV) or intramuscular (IM) injection). However, IV or IM narcotics provide incomplete pain relief and have maternal and fetal/neonatal side effects, e.g., maternal drowsiness, respiratory depression, nausea, vomiting, and neonatal respiratory depression. Other obstetricians allow their patients to request early neuraxial (spinal or epidural) analgesia. The results of several studies comparing patients who received epidural versus IV/IM narcotic labor analgesia (not specifically in early labor)suggest that initiation of early neuraxial analgesia may be associated with higher Cesarean delivery rates. It has been hypothesized that epidural/spinal local anesthetics may induce pelvic musculature relaxation leading to failure of fetal descent and rotation. However, early pain may be a marker for other factors that increase the risk of Cesarean delivery, e.g., large or malpositioned baby, or dysfunctional labor. Whether or not early neuraxial analgesia (particularly if narcotic based, which would not cause pelvic muscle paralysis) compared to IV/IM narcotics, adversely affects the outcome of labor has not been studied in a randomized, prospective fashion. The purpose of this study is to compare Cesarean and forcep delivery rates, and quality of pain relief, in first-time mothers undergoing induction of labor who receive neuraxial versus IV/IM analgesia for early labor (cervical dilation < 4 cm).

• Study Type: Interventional
• Enrollment (Actual): 1026
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Illinois
    • Chicago, Illinois, United States, 60611
      • Northwestern Memorial Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Female

Description

Inclusion Criteria:

• induction of labor
• nulliparity
• >36 weeks gestation
• singleton
• vertex position
• cervical dilation < 4 cm at first request for analgesia
• desires neuraxial analgesia

Exclusion Criteria:

• spontaneously laboring
• multiparity
• nonvertex presentation
• at or >4cm at analgesia request
• chronic opioid therapy
• acute opioid therapy within 4 hours of analgesia request
• allergy to study drugs (hydromorphone, fentanyl, bupivacaine, lidocaine)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: early analgesia:combined-spinal epidural	Procedure: combined spinal epidural analgesia; Analgesia was initiated in the early group using a standard needle-through-needle technique with intrathecal fentanyl 25 mcg and an epidural test dose of lidocaine 15 mg/ml and epinephrine 5 mcg/ml in 3ml. At the second analgesia request, the cervix was examined. Epidural analgesia was initiated with a dilute bupivicaine/fentanyl solution if the cervix was less than 4 cm. If the cervix was 4 cm or more, epidural analgesia was initiated with bupivicaine 1.25 mg/ml. If no cervical exam was performed at the second request for analgesia, the cervix was assumed to be at least 4 cm dilated. Thereafter, analgesia was maintained in all participants in the early group with patient-controlled epidural analgesia.; Other Names: CSE
Active Comparator: late analgesia (systemic)	Procedure: late analgesia (systemic); Analgesia was initiated in the late group with hydromorphone 1mg intramuscularly (IM) and 1 mg intravenously (IV). If the cervix was less than 4 cm at the second analgesia request, hydromorphone analgesia was repeated. Epidural analgesia was initiated with bupivicaine 1.25 mg/ml if the cervix was 4 cm or more. At the third analgesia request, epidural analgesia was initiated regardless of cervical dilation. Thereafter, epidural analgesia was maintained with patient controlled analgesia until delivery.; Other Names: Dilaudid, narcotic

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Delivered by Cesarean Section	The decision to proceed to operative delivery was made by the obstetric team for maternal or fetal indications.	Time form initiation of labor analgesia to delivery (up to 24 hours)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Instrumented Vaginal Delivery	The decision to proceed to assisted/instrumental delivery was made by the obstetric team for maternal or fetal indications.	At time of decision for delivery
Duration of Labor	Labor was induced by initiating an oxytocin infusion or by infusing extra-amniotic saline followed by oxytocin. All participants had continuous external electronic fetal heart rate (FHR) monitoring and tocodynamometry. Internal fetal scalp electrodes were placed when the external tracing was not interpretable, and intrauterine pressure catheters were used to measure the intensity of contractions when deemed necessary by the obstetricians. Artificial rupture of membranes was performed, and nurses titrated oxytocin infusions according to institutional protocol.	Initiation of induction of labor to time of delivery
Indication for Cesarean Delivery	The decision to proceed to operative delivery was made by the obstetric team for maternal or fetal indications.	At time of decision for delivery
Analgesia Efficacy	Patients were asked to rate their average pain score using an 11-point verbal rating score (VRS)for pain (0 - 10: 0= no pain, 10= worst pain imaginable) between 1st and 2nd analgesia request.	At first and second analgesia requests
Nausea	Participants were asked to rate their nausea (as none, mild, moderate, or severe) and report the presence or absence of vomiting.	At second analgesia request
Neonatal Outcome (APGAR Score < 7 at 5 Minutes)	Infant's Apgar scores measured at 5 minutes of life and were assigned by nurses and pediatricians responsible for neonatal assessment. The Apgar score is determined by evaluating the newborn baby on five simple criteria on a scale from zero to two, then summing the five values. The categories are skin color, pulse, reflex to stimulation, muscle tome, and breathing. The test was done at one and five minutes after birth, and may be repeated later if the score is and remains low. Scores 3 and below are generally regarded as critically low, 4 to 6 fairly low, and 7 to 10 generally normal.	APGAR score at 5 minutes
Vomiting	Vomiting during labor analgesia	Vomiting at second analgesia request

Collaborators and Investigators

• Sponsor: Northwestern University
• Collaborators: International Anesthesia Research Society (IARS)
• Investigators: Principal Investigator: Cynthia A Wong, MD, Northwestern University

Publications and helpful links

General Publications

• Wong CA, Scavone BM, Peaceman AM, McCarthy RJ, Sullivan JT, Diaz NT, Yaghmour E, Marcus RJ, Sherwani SS, Sproviero MT, Yilmaz M, Patel R, Robles C, Grouper S. The risk of cesarean delivery with neuraxial analgesia given early versus late in labor. N Engl J Med. 2005 Feb 17;352(7):655-65. doi: 10.1056/NEJMoa042573.

Study record dates

Study Major Dates

• Study Start: October 1, 2001
• Primary Completion (Actual): September 1, 2008
• Study Completion (Actual): September 1, 2008

Study Registration Dates

• First Submitted: September 25, 2006
• First Submitted That Met QC Criteria: September 25, 2006
• First Posted (Estimate): September 27, 2006

Study Record Updates

• Last Update Posted (Estimate): April 14, 2014
• Last Update Submitted That Met QC Criteria: March 17, 2014
• Last Verified: March 1, 2014

More Information

Terms related to this study

• Keywords: cesarean section; epidural analgesia; labor pain; local anesthetics; opioid analgesics; labor induced
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Labor Pain; Physiological Effects of Drugs; Central Nervous System Depressants; Peripheral Nervous System Agents; Analgesics; Sensory System Agents; Narcotics
• Other Study ID Numbers: 0524-009