Clinical trial NCT02584803: Inferior Vena Cava Assessment in Term Pregnancy Using Ultrasound: a Feasibility Study of Subxiphoid and RUQ Views
Official title: Inferior Vena Cava Assessment in Term Pregnancy Using Ultrasound: a Feasibility Study of Subxiphoid and RUQ Views
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Hypotension
Hypovolemic Shock
Lead sponsor: London Health Sciences Centre Research Institute OR Lawson Research Institute of St. Joseph's
Sponsor class: OTHER
First posted: 2015-10-23
Enrollment: 30
Sex: FEMALE
Minimum age (years): 18
Maximum age (years): 45
Standard ages: ADULT
Accepts healthy volunteers: no
Observational model: CASE_ONLY
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Full term pregnant patient coming for elective cesarean section

Brief summary: This study is to assess the feasibility of 2 different ultrasound views of the inferior vena cava (IVC), a large vein that returns blood to the heart. Ultrasound is safe in pregnancy and, is regularly used to evaluate the fetus. It is hoped that imaging of the IVC will then allow us to determine the fluid status of the parturient which could be helpful in treating hemodynamic instability. This study will not involve any change in management of the participating patients.

Detailed description: Anesthesiology consultants and trainees with US experience will first perform scans from the RUQ view starting on the mid-axillary line at the T4 intercostal space, looking to obtain a view of the IVC as it enters the right atrium (RA). Following successful acquisition, the examiner will perform scan from the subxiphoid position, looking to obtain the same view of the IVC transitioning into the RA. Primary endpoint will be time to obtaining quality of images. The investigator will use a stopwatch to time acquisition of images. If the duration of scanning exceeds ten minutes, the scan will be discontinued and labeled as failed. Each image will be separately reviewed by 2 different US specialists with extensive US experience. Images will be assessed according to a Likert scale from 1 to 5. (Very poor (1), poor (2), acceptable (3), good (4), very good (5)) Secondary endpoints will be assessed as follows: 1. Acceptability: all patients participating in the study will complete a questionnaire to assess acceptability. 2. Comfort: During the exam the patient will have the option to suspend the scan by stating they are uncomfortable and wish to stop. Each request will be noted and taken into the account at data analysis. Furthermore, patients will be given a questionnaire at the end of the scan and asked to rate their comfort level during procedure according to Likert scale. (Very comfortable (5), comfortable (4), equivocal (3), uncomfortable (2), very uncomfortable (1)) 3. Ease of exam: Examiner will rate the ease of image acquirement according to Likert scale. (impossible (1), difficult (2), equivocal (3), easy (4), very easy (5))

Eligibility criteria: Inclusion Criteria:

* Adults pregnant females,
* Age 18-45,
* Term pregnancy Parturients not in established labor Singleton pregnancies

Exclusion Criteria:

* Advanced labor,
* Multiple gestations,
* Maternal or fetal distress,
* BMI \> 45.
* Inability to obtain informed consent

Primary outcomes:
measure: Time to obtaining good Quality IVC images through RUQ and subxiphoid window
timeFrame: 60 seconds
Secondary outcomes:
measure: Patient Acceptability of procedure
timeFrame: 10 seconds
measure: patient comfort
timeFrame: 10 seconds
measure: Ease of exam for the examiner
timeFrame: 10 seconds
Other outcomes:
Locations:
city: London
country: Canada
facility: London Health Science Centre
state: Ontario
Study officials:
affiliation: Western University, Schulish school of Medicine, Department of Anesthesia
name: Indu Singh
role: PRINCIPAL_INVESTIGATOR
References:
citation: Dennis A, Arhanghelschi I, Simmons S, Royse C. Prospective observational study of serial cardiac output by transthoracic echocardiography in healthy pregnant women undergoing elective caesarean delivery. Int J Obstet Anesth. 2010 Apr;19(2):142-8. doi: 10.1016/j.ijoa.2009.06.007. Epub 2010 Mar 3.
citation: Dennis AT. Transthoracic echocardiography in obstetric anaesthesia and obstetric critical illness. Int J Obstet Anesth. 2011 Apr;20(2):160-8. doi: 10.1016/j.ijoa.2010.11.007. Epub 2011 Feb 18.