Pharmacokinetics of Oxytocin at Cesarean Delivery

Completed

• Conditions: Postpartum Hemorrhage
• Interventions: Drug: oxytocin; Device: Shore durometer

• Registration Number: NCT03898882
• Lead Sponsor: Washington University School of Medicine

Brief Summary

The primary objective is to obtain data to inform the design of a population pharmacokinetic study of oxytocin after administration at CD as per standard institutional practice.

Detailed Description

In this pilot study the investigators will compare plasma oxytocin concentrations measured in arterial and venous blood, after oxytocin administration at cesarean delivery, in order to assess the validity of venous samples. They will also measure oxytocinase to explore how levels vary around the time of delivery of the placenta and to assess the effect that this may have on the metabolism of oxytocin.

Study Timeline

• Study First Submitted: 2019-03-29
• Study First Submitted QC: 2019-03-29
• Study First Posted: 2019-04-02
• Study Start: 2019-05-24
• Primary Completion: 2020-02-28
• Study Completion: 2020-02-28
• Status Verified: 2020-05
• Last Update Submitted: 2020-05-06
• Last Update Posted: 2020-05-07

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Female
• Target Recruitment: 30

Inclusion Criteria

• Term singleton pregnancy
• Age 18-45 years of age
• ASA classification 2 or 3
• Scheduled cesarean delivery under neuraxial anaesthesia

Exclusion Criteria

• Age or ASA classification outside of inclusion criteria
• Need for general anaesthesia
• Absence of consent
• Inability to communicate in English or other barrier to providing informed consent

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
BMI 20 - 29.9 kg/m2	Shore durometer	-
BMI > 30 kg/m2	Shore durometer	-
BMI 20 - 29.9 kg/m2	oxytocin	-
BMI > 30 kg/m2	oxytocin	-

Primary Outcome Measures

Name	Time	Method
Venous [OXT]	Scheduled samples during the first 30 minutes after oxytocin administration	Concentration of oxytocin in venous samples
Arterial [OXT]	Scheduled samples during the first 30 minutes after oxytocin administration	Concentration of oxytocin in arterial samples

Secondary Outcome Measures

Name	Time	Method
Nausea & Vomiting	Recorded intraoperatively	Incidence of nausea and vomiting
Arterial [OXTase]	Scheduled samples during the first 30 minutes after oxytocin administration	Concentration of oxytocinase in arterial samples
Hypotension	Measured intraoperatively	Incidence of systolic BP reduced by 20% from baseline
Uterine tone	Scheduled measurements during the first 30 minutes after oxytocin administration	Uterine tone measured using a Shore Durometer or assessed by obstetrician using numerical rating score (NRS, 0-10)
EBL	Estimated at the end of surgery	Estimated blood loss in milliliters

Trial Locations

Locations (1)

Washington University in St. Louis; 🇺🇸 Saint Louis, Missouri, United States