Could the Cerebral Oximetry be a Good Technology to Measure Placental Oxygenation?

Could the Cerebral Oximetry (NIRS) be a Good Technology to Measure Placental Oxygenation in Pregnant Woman?

To assess the potential of the cerebral oximeter to measure placental oxygenation

Study Overview

• Status: Completed
• Conditions: Placental Oxygenation
• Intervention / Treatment: Device: cerebral oximetry

Detailed Description

There is general agreement among experts to recommend the use of phenylephrine as first line therapy for the treatment of arterial hypotension induced by spinal anaesthesia during caesarean delivery. In some studies, there are trends toward a lower PaO2 values in the umbilical cord venous blood when the mother receive this vasopressor. These findings may be a result of the vasoconstrictor effect of phenylephrine on utero-placental vessels, and a subsequent increased oxygen extraction by the fetus. The possibility to extract more oxygen would provide a certain "safety margin" in the event of compromised utero-placental blood flow during normal pregnancy. However, this "safety margin" should not be taken for granted in cases where signs of fetal distress are present, and this situation might influence the choice of vasopressors.

It is well establish on a physiological basis that during labour, utero-placental blood flow is lower during the contractions. This lower blood flow could result in a lower saturation value measured by the cerebral oximeter.

Twenty patients in labour will be included in this study. Patients will be recruited in obstetric clinic during pregnancy. Based on the second trimester ultrasound, patients with anterior placenta will be included.

During labour, once a functional epidural is in place, an Invos oximeter will be install. Two sensors will be applied on the abdomen (one above the placenta and the other above the myometrium at a place without placenta). Two sensors will also be applied on the extremities (forearm and leg).Saturation values and timing of the contractions will be recorded for sixty minutes. Half of the recording will be done with an oxygen mask. Vitals signs will also be registered every five minutes.

• Study Type: Observational
• Enrollment (Actual): 20

Contacts and Locations

Study Locations

• Canada
  • Quebec
    • Montreal, Quebec, Canada, H1T 2M4
      • Maisonneuve Rosemont Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Female

• Sampling Method: Non-Probability Sample

Study Population

healthy pregnant woman at term gestation in labour

Description

Inclusion Criteria:

• healthy pregnant woman (ASA I or II)
• Term gestation ( > 37 weeks)
• Normal pregnancy
• vaginal delivery
• obstetrical epidural in place
• anterior placenta

Exclusion Criteria:

• patient refusal
• Any contraindication to neuraxial anesthesia
• cesarean section
• multiple gestation
• placentation abnormalities
• anormal placental perfusion
• Placental Abruption

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort

Intervention / Treatment

anterior placenta; Cerebral oximetry device used to obtain: Saturation value of the placenta probe with no oxygen, saturation value of the placenta probe with oxygen, saturation value of the myometrium probe with no oxygen saturation value of the myometrium probe with oxygen saturation value of the forearm probe with no oxygen, saturation value of the forearm probe with oxygen saturation value of the leg probe with no oxygen saturation value of the leg probe with oxygen Timing between the contractions measure by cardiotocography

Device: cerebral oximetry; tissue saturation measurement in pregnant women; Other Names: NIRS; INVOS

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Difference between Δp and Δm	Δp = Difference between the mean value area under the curve for the placenta and arm = (Ap- Af) Δm= Difference between the mean value area under the curve for the myometrium and arm = (Am- Af)	60 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Difference of the area under the curve of saturation with and without oxygen	Ap with Oxygen - Ap without oxygen; Am with oxygen - Am without oxygen	60 minutes

Collaborators and Investigators

• Sponsor: Maisonneuve-Rosemont Hospital
• Collaborators: Université de Montréal
• Investigators: Principal Investigator: Christian Loubert, MD, FRCPC, Maisonneuve-Rosemont Hospital

Study record dates

Study Major Dates

• Study Start: April 1, 2013
• Primary Completion (Actual): July 1, 2013
• Study Completion (Actual): July 1, 2013

Study Registration Dates

• First Submitted: April 15, 2013
• First Submitted That Met QC Criteria: April 15, 2013
• First Posted (Estimate): April 18, 2013

Study Record Updates

• Last Update Posted (Estimate): April 15, 2016
• Last Update Submitted That Met QC Criteria: April 14, 2016
• Last Verified: April 1, 2016

More Information

Terms related to this study

• Keywords: NIRS; cerebral oximetry; obstetric anesthesia; cerebral oximeter; placental oxygenation
• Other Study ID Numbers: LoubertHMR2013/04