Pharmacokinetic and Pharmacodynamic Investigations of Fetal Anesthesia During Maternal Fetal Surgery

Status

Not yet recruiting

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT07571811

Enrollment

Registered

2026-05-06

Start date

2026-05-01

Completion date

2027-05-01

Last updated

2026-05-06

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Fetal Anesthesia

Keywords

fetal anesthesia, fetal, intrauterine, fetal cardiac intervention, iut, intrauterine transfusion

Brief summary

This study examines how three medications commonly used during fetal surgery, fentanyl, rocuronium, and atropine, behave in the fetus. The primary goal is to understand their pharmacokinetics (how the drugs are absorbed, distributed, and cleared), pharmacodynamics (how they affect fetal physiology), and how they transfer between mother and fetus through the placenta. The secondary goal is to measure drug levels in discarded fetal blood samples collected during clinically indicated procedures and relate those levels to fetal heart rate, heart rate variability, movement, gestational age, and fetal size. An optional maternal blood draw component will allow comparison of maternal and fetal drug concentrations to better understand placental transfer. The study does not change clinical care or require extra fetal procedures, and findings may help create safer, evidence-based fetal anesthesia dosing strategies tailored to gestational age.

Interventions

None listed

Study design

Observational model

CASE_ONLY

Time perspective

PROSPECTIVE

Eligibility

Sex/Gender

FEMALE

Age

13 Years to No maximum

Healthy volunteers

Yes

Inclusion criteria

* Pregnant and undergoing maternal-fetal surgery requiring clinically indicated fetal anesthesia and planned fetal blood sampling as part of usual fetal care * Fetus is with or without congenital heart disease

Exclusion criteria

* Patient or fetus have any known liver or kidney disease * Patient or fetus has any known allergy to fentanyl, rocuronium, or atropine * Patient has taken inhibitors, inducers or substrates of CYP3A4 other than midazolam (including erythromycin, ranitidine, verapamil, antihistamines, and dextromethorphan) within 24 hours of surgery.

Design outcomes

Primary

Measure	Time frame	Description
Maximum plasma concentration (Cmax) of fetal anesthesia	2 years	Characterize the plasma concentrations / pharmacokinetics profile, specifically the peak plasma concentration (Cmax) of commonly used fetal anesthetics, investigate the pharmacodynamic effects of anesthetics on fetus, assess the maternal-fetal transfer of anesthetics during surgery, and identify potential variations during different stages of fetal development.
Area under the plasma concentration versus time curve (AUC) of fetal anesthesia	2 years	Characterize the plasma concentrations / pharmacokinetics profile, specifically the area under the plasma concentration versus time curve (AUC) of commonly used fetal anesthetics, investigate the pharmacodynamic effects of anesthetics on fetus, assess the maternal-fetal transfer of anesthetics during surgery, and identify potential variations during different stages of fetal development.

Secondary

Measure	Time frame	Description
Maternal blood concentration of fetal anesthesia	2 years	Measure the maternal blood concentration of fetal anesthesia to characterize fetal-maternal transfer of commonly used fetal anesthetics.
Fetal blood concentration of maternal anesthesia	2 years	Measure the fetal blood concentration of maternal anesthesia to characterize fetal-maternal transfer of commonly used maternal anesthetics.

Countries

United States

Contacts

CONTACTJulia Atayde, BS

julia.atayde@childrens.harvard.edu617-355-2967

CONTACTRachel Bernier, BS, MPH

rachel.bernier@childrens.harvard.edu857-218-5348

Outcome results