Effects of Ephedrine, Phenylephrine, Norepinephrine and Vasopressin on Contractility of Human Myometrium and Umbilical Vessels: An In-vitro Study

What Was Tested

This registered not phased trial tested Vasopressin.

Hypotension during cesarean deliveries can have detrimental effects on the mother and neonate.

It had 12 arms (groups): Myometrium + Ephedrine (experimental), Myometrium + Phenylephrine (experimental), Myometrium + Norepinephrine (experimental), Myometrium + Vasopressin (experimental) and Umbilical artery + Ephedrine (experimental).

The registry classes the interventions as drug.

More on the Plan

One of the major concerns addressed in the literature is the risk of fetal acidosis related to the use of vasopressors, which varies according to the type of drug used.

This can occur indirectly via compression of vessels due to myometrial contractions or directly by vasoactive effects on umbilical vessels.

So far, no studies have directly explored the role of the aforementioned vasopressors on myometrial contractions and umbilical vessel vasoconstriction.

An in-vitro approach in isolated tissues will eliminate many clinical confounding variables, allowing direct comparison of the drugs in a controlled environment, and providing insight into the contractile mechanisms responsible for their neonatal effects.

Who Took Part

The registry lists 144 planned participants were the target.

It was open to women only aged from 19 years up to 40 years.

Healthy volunteers could join, not only people with the condition.

Examples of who could join: Patients who give written consent to participate in this study. Patients with gestational age 37-41 weeks. Patients of 19-40 years. Non-laboring patients, not exposed to exogenous oxytocin. Patients requiring elective primary or first repeat caesarean delivery.

The full record lists 6 inclusion and 7 exclusion criteria; among the exclusions: patients who refuse to give written informed consent; patients who require general anesthesia; patients in labor and those receiving oxytocin for induction of labor.

How the Study Was Run

It was run as a non-randomized, parallel-group and open-label study.

The Vasopressin group and the comparison group ran side by side rather than switching.

Being open-label, the Vasopressin study did not mask who received what.

It started in 2019-07-08 with completion listed for 2026-12.

It ran at 1 site in Canada.

Its stated primary purpose is treatment.

What Was Measured

The main thing measured (primary outcome): Motility index (time frame: 4 hours).

It also tracked 3 secondary outcomes, for example Amplitude of contraction, Frequency of contraction and Integrated area under response curve (AUC).

What This Means in Plain Language

Put simply, this is a not phased, non-randomized trial of Vasopressin in 144 people.

It is still recruiting; no results are posted to the registry yet, so nothing here describes outcomes.

More context: the Vasopressin compound page, all human trials.