Clinical trial NCT04813874: Nitrous Oxide and Neuraxial Labor Analgesia Use on Maternal Fetal Outcomes
Official title: Evaluation of Maternal and Fetal Outcomes Following Nitrous Oxide and Neuraxial Labor Analgesia
Study type: OBSERVATIONAL
Overall status: WITHDRAWN
Conditions: Pregnancy
Lead sponsor: Brigham and Women's Hospital
Sponsor class: OTHER
First posted: 2021-03-24
Enrollment: 0
Sex: FEMALE
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: CASE_CONTROL
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Pregnant patients requesting for pain relief with neuraxial analgesia and/or nitrous oxide

Brief summary: The purpose of this study is to evaluate maternal and neonatal outcomes in parturients who used nitrous oxide and neuraxial labor analgesia during labor.

Detailed description: The use of nitrous oxide during labor is common in several countries including the United Kingdom, Finland, Canada, Australia and New Zealand.1, 2 The use of nitrous oxide during labor has undergone a resurgence in popularity recently in the United States and became available at Brigham and Women's hospital in August 2014.

Inhaled nitrous oxide has a rapid onset (30-50 seconds) and clearance with a half-life of about 5 minutes.3 It can be used for analgesia during the first, second and third stages of labor, as well as during post-delivery procedures such as laceration repair, manual removal of the placenta, and uterine curettage. It is also commonly used to facilitate the initiation of epidural analgesia.4 At the Brigham and Women's Hospital, a pneumatically driven gas mixer is designed to deliver a 50% oxygen and 50% nitrous oxide mixture to patients. Nitrous oxide passes readily across the placenta, and reaches equilibrium within a few minutes; the fetal maternal concentration ratio after 2 minutes of inhalation is 0.64.5 Hence, when administered at 50% concentration to the mother, the fetal concentration approximates at 32%.

Despite its long track record of maternal safety reported in numerous countries, the effect of nitrous oxide on the fetus is less well-studied. A number of studies have published data on the use of nitrous oxide for labor analgesia, including the effectiveness in labor analgesia, maternal satisfaction and maternal fetal adverse effects. Most of these studies have not identified adverse neonatal outcomes. However, these studies used Apgar scores or neonatal behavior scores as outcome measures and the quality of these studies was predominately poor.

The purpose of this study is to evaluate maternal and neonatal outcomes in parturients who used nitrous oxide and neuraxial labor analgesia during labor.

Eligibility criteria: Inclusion Criteria:

* Pregnant patients requesting for pain relief with neuraxial analgesia and/or nitrous oxide
* health patients with no comorbidities
* singleton, vertex gestation at term

Exclusion Criteria:

* Refuse informed consent
* evidence of anticipated fetal anomalies
* significant medical or pregnancy-related diseases

Primary outcomes:
measure: Fetal and Neonatal Outcomes
timeFrame: At 1 minute following birth
measure: Fetal and Neonatal Outcomes
timeFrame: At 5 minutes following birth
measure: Fetal and Neonatal Outcomes
timeFrame: At 10 minutes following birth
Secondary outcomes:
measure: Maternal Outcome
timeFrame: During Labor at 90 minute intervals
measure: Maternal Outcome
timeFrame: Any Time During Labor
measure: Maternal Outcome
timeFrame: At Delivery
Other outcomes:
Locations:
Study officials:
References: