Plain English Summary
Background and study aims
Oxytocin is a drug routinely used in women to induce contraction of the uterus and prevent bleeding after childbirth. However it has side effects on the blood pressure and the heart which in some patients could lead to serious events.
This study aims to further investigate the effects of oxytocin on the human heart and blood vessels.
Who can participate?
Women aged 18 and over scheduled for termination of pregnancy in first trimester
What does the study involve?
Participants are randomly assigned to one of two groups. Those in the first group receive Oxytocin injections either early or late during the medical abortion, whilst under general anaesthetic. Those in the second group receive a placebo (dummy) injection either early or late during the medical abortion, whilst under general anaesthetic.
Participants are monitored using a pain-free device that analyses the pulse wave (change in blood volume as the heart contracts) in the finger, and a system that monitors blood pressure, heart rate and heart activity during the anaesthetic.
What are the possible benefits and risks of participating?
Participants may benefit from further knowledge about the cardiovascular effects of oxytocin in a clinical setting. The study protocol does not differ from standard clinical procedure, except randomization and further non-invasive, non-painful monitoring.
Where is the study run from?
Skåne University Hospital (Sweden)
When is the study starting and how long is it expected to run for?
August 2012 – January 2017
Who is funding the study?
1. Lund University (Sweden)
2. Region Skåne (Sweden)
Who is the main contact?
Professor Per Olofsson (Scientific)
per.olofsson@med.lu.se
Trial website
Contact information
Type
Scientific
Primary contact
Prof Per Olofsson
ORCID ID
http://orcid.org/0000-0001-7840-525X
Contact details
Lund University
Box 117
Lund
22100
Sweden
Additional identifiers
EudraCT number
ClinicalTrials.gov number
Protocol/serial number
1
Study information
Scientific title
Effects of oxytocin and anaesthesia on vascular tone in pregnant women: a randomised double-blind placebo-controlled study using non-invasive pulse wave analysis
Acronym
Study hypothesis
Oxytocin decreases vascular tone and elevates cardiac output in first trimester pregnacy
Ethics approval
Regional Research Ethics Committee in Lund, 13/12/2012, ref: 2012/649
Study design
Randomised double-blind placebo-controlled single centre study
Primary study design
Interventional
Secondary study design
Randomised controlled trial
Trial setting
Hospitals
Trial type
Diagnostic
Patient information sheet
See additional file (in Swedish)
Condition
Vascular tone and hemodynamic change in pregnancy
Intervention
Participants are randomised by a web-based random number generator to a treatment or placebo group. Those in the treatment group receive 8.3 µg (5 U) Oxytocin by injection during the first trimester surgical evacuation of the gravid uterus under general anaesthesia. Those in the control group receive a placebo injection. The injections are administered once either early or late in the procedure, in a double-blind fashion.
The effects of oxytocin on the heart and the vascular tree are assessed using digital photoplethysmography pulse wave analysis (DPA) variables. The Meridian DPA (TM) works through an infra-red light emitting diode and receiver, measuring light absorption through the finger. The pulse wave through the finger augments the light absorption, and computer analysis generates a pulse volume curve. From the analysis of the waveform of this curve, hemodynamic estimates are computed and presented as 17 different variables. Some of these are shown to have the best repeatability, these are used in this study.
Also, heart rate, mean arterial blood pressure and electrocardiographic ST index are recorded. These variables are noted before and after induction of anaesthesia and 1 minute after each injection. No further follow up. DPA variables together with the other variables make it possible to assess the LV ejection function and vascular tone, possibly differentiating between that of large or small arteries.
Intervention type
Drug
Phase
Drug names
Oxytocin, Propofol
Primary outcome measure
The effect of oxytocin on vascular tone and cardiac LV ejection fraction is assessed using digital photoplethysmography pulse wave analysis (DPA) variables before and 1 minute after each injection.
Secondary outcome measures
The effect of anaesthesia on vascular tone and cardiac LV ejection fraction is assessed by digital photoplethysmography pulse wave analysis (DPA) variables before and after induction of anaesthesia.
Overall trial start date
01/08/2012
Overall trial end date
01/01/2017
Reason abandoned (if study stopped)
Eligibility
Participant inclusion criteria
1. Women
2. Aged 18 years and over
3. Scheduled for termination of pregnancy in the first trimester by vacuum aspiration or curettage
Participant type
Patient
Age group
Adult
Gender
Female
Target number of participants
51
Participant exclusion criteria
1.Gestational age above 12 weeks in viable pregnancies
2. Age less than 18 years
3. Do not understand Swedish
4. Serious cardiovascular disorders.
Recruitment start date
01/01/2013
Recruitment end date
01/06/2013
Locations
Countries of recruitment
Sweden
Trial participating centre
Skåne University Hospital
Malmö
20502
Sweden
Sponsor information
Organisation
Lund University
Sponsor details
Box 117
Lund
22100
Sweden
+46 46 222 0000
lu@lu.se
Sponsor type
University/education
Website
Organisation
Skåne University Hospital
Sponsor details
Diarium
Rådhus Skåne
Kristianstad
29189
Sweden
+46 40 331 000
region@skane.se
Sponsor type
Hospital/treatment centre
Website
Funders
Funder type
Government
Funder name
Lunds Universitet
Alternative name(s)
Lund University
Funding Body Type
government organisation
Funding Body Subtype
government non-federal
Location
Sweden
Funder name
Region Skåne
Alternative name(s)
Funding Body Type
Funding Body Subtype
Location
Results and Publications
Publication and dissemination plan
Planned publication in a high-impact peer reviewed journal.
IPD sharing statement:
The datasets generated during and/or analysed during the current study are/will be available upon request from Dr Sofus Rabow (sofus.rabow@med.lu.se)
Intention to publish date
01/06/2018
Participant level data
Available on request
Basic results (scientific)
Publication list