Clinical trial NCT01689311: In Vitro Myometrial Contractions in Laboring and Non-laboring Women
Official title: In Vitro Myometrial Contractions in Laboring and Non-laboring Women: Oxytocin is Superior to Other Uterotonic Agents
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Postpartum Hemorrhage
Keywords: Uterine contraction
Dose response
Non-laboring
Laboring
Laboring with oxytocin augmentation
Oxytocin
Ergonovine
Prostaglandin F2alpha
Misoprostol
Lead sponsor: Samuel Lunenfeld Research Institute, Mount Sinai Hospital
Sponsor class: OTHER
Collaborators: name: University of Toronto
name: Canadian Anesthesiologists' Society
First posted: 2012-09-21
Enrollment: 53
Sex: FEMALE
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: TREATMENT

Brief summary: The purpose of this study is to compare the ability of an isolated sample of uterine muscle tissue (in a tissue bath) to contract in the presence of various drugs. The drugs studied--uterotonics--are typically used to contract the uterus when a pregnant patient continues to bleed after delivery. Amongst common uterotonic drugs, namely oxytocin, ergonovine, prostaglandin F2alpha, and misoprostol, the most effective one to use is unknown.

The investigators will be testing isolated uterine muscle samples to increasing concentrations of these four drugs in three patient populations: non-laboring, laboring without exogenous oxytocin augmentation, and laboring with oxytocin augmentation. Contractile measures will be measured and compared between all groups. The investigators hypothesize that oxytocin alone will have a weaker uterotonic effect in oxytocin-augmented laboring patients, and all four drugs will induce different patterns of contractions.

Detailed description: Postpartum hemorrhage (PPH) is a major cause of maternal mortality and morbidity. In 80% cases of PPH, the primary cause is failure of the uterus to contract after delivery of the baby, which then requires further treatment of the mother with uterotonic drugs (drugs used to contract uterus and thus prevent bleeding).

Patients participating in this study will be asked to donate a very small sample of uterine tissue during Cesarean section, which will be tested in the laboratory for the ability to contract in response to the uterotonics oxytocin, ergonovine, prostaglandin F2alpha, and misoprostol. We will seek to better understand the effects of these drugs by comparing their contractile capability in isolated uterine tissue.

Eligibility criteria: Inclusion Criteria:

* Gestational age 37-41 weeks
* Patients requiring primary or first repeat Cesarean section
* Cesarean section under spinal anesthesia

Exclusion Criteria:

* Patients who require general anesthesia
* Patient who had previous myometrial surgery or more than one previous Cesarean section
* Patients with placental anomalies
* Patients with multiple pregnancy (twins, etc.)

Primary outcomes:
measure: Amplitude of contraction
timeFrame: 4-5 hours
Secondary outcomes:
measure: Integrated area under response curve (AUC)
timeFrame: 4-5 hours
measure: Basal tone
timeFrame: 4-5 hours
measure: Frequency of contraction
timeFrame: 4-5 hours
Other outcomes:
Locations:
city: Toronto
country: Canada
facility: Mount Sinai Hospital
state: Ontario
Study officials:
affiliation: MOUNT SINAI HOSPITAL
name: Mrinalini Balki, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Balki M, Erik-Soussi M, Kingdom J, Carvalho JC. Comparative efficacy of uterotonic agents: in vitro contractions in isolated myometrial strips of labouring and non-labouring women. Can J Anaesth. 2014 Sep;61(9):808-18. doi: 10.1007/s12630-014-0190-1. Epub 2014 Jun 7.