Gastric Sonography in the Fasted Term Pregnant Patient for Elective Cesarean Delivery

Gastric Sonography in the Fasted Term Pregnant Patient for Elective Cesarean Delivery: a Prospective Descriptive Study

Food residue in the stomach of patients scheduled to have surgery is considered a major risk factor for pulmonary aspiration of gastric contents. The resulting respiratory compromise after aspiration is associated with significant morbidity and mortality. The risk of pulmonary aspiration is especially important in pregnant women, as they may often require surgery without having observed appropriate fasting. In pregnant patients scheduled for elective surgery, standard preoperative guidelines apply as the general non-pregnant surgical population (8-hour fasting of solid food and 2-hour fasting of clear fluids). A bedside ultrasound assessment of the status of the gastric content and volume would be of great value for the clinician. This technique has recently been shown very promising in fasted non-pregnant patients scheduled for elective surgery. Therefore, it is important to study its feasibility in the pregnant population scheduled for elective Cesarean Delivery.

The investigators hypothesize that no residual solid contents will be found in the gastric sonography, and a small volume of gastric fluid will be observed in the antrum in both supine and right lateral decubitus.

Study Overview

• Status: Completed
• Conditions: Respiratory Aspiration; Pregnancy
• Intervention / Treatment: Device: Ultrasound

Detailed Description

The aim of this prospective study is to provide a qualitative and quantitative description of the sonographic appearance of the gastric antrum in fasted pregnant undergoing elective Cesarean delivery.

The investigators expect that the information obtained from the systematic ultrasonographic qualitative/quantitative assessment of the gastric content may help anesthesiologist to better assess aspiration risk and guide anesthetic and airway management, particularly in pregnant women scheduled for elective Cesarean delivery after standard preoperative fasting guidelines.

• Study Type: Observational
• Enrollment (Actual): 103

Contacts and Locations

Study Locations

• Canada
  • Ontario
    • Toronto, Ontario, Canada, M5G1X5
      • Mount Sinai Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 55 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Female

• Sampling Method: Non-Probability Sample

Study Population

Term pregnant patients who have scheduled elective cesearean sections.

Description

Inclusion Criteria:

• Non-labouring pregnant women at term (≥ 36 weeks)
• 18 years or older
• ASA Physical Status I-III
• 50-120 kg of weight
• 150 cm of height or taller
• Ability to understand the rationale of the study assessments and to provide signed informed consent
• Written informed consent

Exclusion Criteria:

• Known pre-existing abnormal anatomy of the upper gastrointestinal tract
• History of upper GI tract surgical procedure

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Term pregnant patients; Term pregnant patients for scheduled elective cesarean section will be examined using a portable ultrasound machine to evaluate gastric contents.	Device: Ultrasound; Two-dimensional portable ultrasound unit with a low frequency (2-5 MHz) curved array transducer

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Qualitative assessment of the antrum of the stomach	Patients will be classified as follows; Grade 0: the antrum appears empty on both supine and right lateral decubitus positions; grade 1: gastric fluid is visible on the right lateral decubitus position only, suggesting a small fluid volume; and grade 2: gastric fluid is observed in the antrum in both supine and right lateral decubitus, suggesting a larger fluid volume.	10 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Quantitative assessment of the antrum of the stomach	Three consecutive measures of the CSA (cross sectional area) of the antrum will be calculated via the ultrasound machine (free tracing method).	10 minutes

Collaborators and Investigators

• Sponsor: Samuel Lunenfeld Research Institute, Mount Sinai Hospital
• Investigators: Principal Investigator: Cristian Arzola, MD, Mount Sinai Hospital

Study record dates

Study Major Dates

• Study Start: October 1, 2013
• Primary Completion (Actual): May 1, 2014
• Study Completion (Actual): May 1, 2014

Study Registration Dates

• First Submitted: November 4, 2013
• First Submitted That Met QC Criteria: November 4, 2013
• First Posted (Estimate): November 8, 2013

Study Record Updates

• Last Update Posted (Estimate): June 19, 2014
• Last Update Submitted That Met QC Criteria: June 18, 2014
• Last Verified: June 1, 2014

More Information

Terms related to this study

• Keywords: Ultrasound; Pregnancy; Respiratory Aspiration; Gastric Contents
• Additional Relevant MeSH Terms: Pathologic Processes; Respiratory Tract Diseases; Respiration Disorders; Respiratory Aspiration
• Other Study ID Numbers: 13-08