Upper Airways in Pregnancy: Evaluation by the Acoustic Reflection Method (MAVAG)

It is well known that airway management can be difficult during pregnancy. Increased risks for difficult intubation in pregnant women have been often reported. Thus, pregnancy is regarded as a period of high anesthesiologic risk.

Generalized weight gain is a well known factor influencing the upper airway in pregnant women. However, the modifications of the airway itself are less well documented.

The acoustic reflection method is based on the analysis of the reflection of a single transient planar wave allowing the analysis of the longitudinal cross-sectional area profile of the examined cavity. It is a noninvasive and harmless method.

The aim of the study is to evaluate by acoustic reflection method the physiological modifications of the upper airways during pregnancy.

Women enrolled in the study will undergo an acoustic recording during the first, second, and third trimester of pregnancy, as well as two days and one month after delivery. Forty pregnant women will be included in this monocentric, prospective, open labelled study.

Moreover, a single acoustic recording will be performed in 10 other pregnant women undergoing an MRI for obstetrical purpose. The estimated caliber of the upper airways by MRI and acoustic method will be compared.

Study Overview

• Status: Completed
• Conditions: Pregnancy
• Intervention / Treatment: Device: Acoustic reflection method

• Study Type: Observational
• Enrollment (Actual): 50

Contacts and Locations

Study Locations

• France
  • Paris, France, 75012
    • Hôpital d'Enfants Armand Trousseau
  • Paris, France, 75012
    • Armand Trousseau University 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 women

Description

Inclusion Criteria:

• Pregnant women who attend the routine ultrasound control in our institution before 14 weeks of pregnancy will be invited to participate in the study.

• Women are eligible for the study if they are:

  • healthy (no previous disease, hypertension, nor obesity),
  • 18 years or more
  • with a singleton live fetus at the routine ultrasound scan
  • with a normal pregnancy.

Exclusion Criteria:

• Pregnancy complications
• Multiple pregnancy
• High risk for preterm labor
• Underlying diseases that could interfere with the results (such as pre-existing upper airway problems) and participation.

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Physiological modifications; Pregnant women who attend the routine ultrasound control in our institution before 14 weeks of pregnancy	Device: Acoustic reflection method; An acoustic reflection device gives the longitudinal cross-sectional area profile along airways. It is based on the analysis of a planar acoustic wave propagating in a rigid duct connected to airway.
MRI and acoustic; Women undergoing an MRI for obstetrical purpose	Device: Acoustic reflection method; An acoustic reflection device gives the longitudinal cross-sectional area profile along airways. It is based on the analysis of a planar acoustic wave propagating in a rigid duct connected to airway.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Physiological modifications during pregnancy and acoustic reflection method	Main aim: to evaluate by acoustic reflection method the physiological modifications of the upper airways during pregnancy. Women enrolled in the study will undergo an acoustic recording during: the 1st, 2d, and 3d trimester of pregnancy; two days after delivery; one month after delivery	6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
MRI and acoustic reflection method	Secondary aim: a single acoustic recording will be proposed to 10 pregnant women undergoing an MRI for obstetrical purpose. The estimated caliber of the upper airways by MRI and acoustic method will be compared.	6 months

Collaborators and Investigators

• Sponsor: Club d'Anesthésie-Réanimation Pédiatrique Armand Trousseau
• Collaborators: Institut National de la Santé Et de la Recherche Médicale, France
• Investigators: Study Director: Brigitte Fauroux, MD, PhD, Assistance Publique - Hôpitaux de Paris; Principal Investigator: Nicolas LEBOULANGER, MD, Assistance Publique - Hôpitaux de Paris

Publications and helpful links

General Publications

• Kodali BS, Chandrasekhar S, Bulich LN, Topulos GP, Datta S. Airway changes during labor and delivery. Anesthesiology. 2008 Mar;108(3):357-62. doi: 10.1097/ALN.0b013e31816452d3.
• Louis B, Fodil R, Jaber S, Pigeot J, Jarreau PH, Lofaso F, Isabey D. Dual assessment of airway area profile and respiratory input impedance from a single transient wave. J Appl Physiol (1985). 2001 Feb;90(2):630-7. doi: 10.1152/jappl.2001.90.2.630.

Study record dates

Study Major Dates

• Study Start: March 1, 2010
• Primary Completion (Actual): March 1, 2012
• Study Completion (Actual): March 1, 2012

Study Registration Dates

• First Submitted: March 10, 2010
• First Submitted That Met QC Criteria: March 12, 2010
• First Posted (Estimate): March 15, 2010

Study Record Updates

• Last Update Posted (Estimate): June 12, 2012
• Last Update Submitted That Met QC Criteria: June 11, 2012
• Last Verified: June 1, 2012

More Information

Terms related to this study

• Keywords: Pregnancy; Upper airways; Acoustic reflection method
• Other Study ID Numbers: MAVAG