Intra- and Interrater Reliability of Quantitative Ultrasound Assessment of Gastric Content in Term Parturients Before Elective Caesarean Delivery

The presence of solid food or fluid residue in the stomach is always a major concern when patients require medical procedures under sedation or general anesthesia, due to the high risk of pulmonary aspiration of the stomach contents. This is especially important in emergency procedures, when a fasting period could not be observed. Pulmonary aspiration of gastric content is a serious perioperative complication of obstetric anesthesia, and it is associated with morbidity and mortality. Information from a bedside ultrasound assessment of the stomach may be a very useful resource to decide whether it's safe to proceed, cancel or delay a surgical procedure. The ultrasound assessment of the stomach content has shown to be very feasible and practical in non-pregnant patients. However, it has not been determined whether the competence reached by anesthesiologists in non-pregnant subjects can be transferred to the obstetric population, especially in term pregnant patients where it could be difficult to identify the stomach because of the presence of the gravid uterus. Although quantitative assessment of the gastric antrum cross-sectional area in terms of intra- and interrater reliability has been evaluated in non-pregnant adults, it remains to be evaluated in pregnant patients. Furthermore, it has not been determined whether the performance of novice operators is comparable to expert operators in the gastric quantitative assessment. This study aims to determine whether trained anesthesiologists can reliably assess the stomach content of pregnant patients by ultrasound, evaluating the inter- and intra-rater reliability of quantitative gastric ultrasound in term pregnant patients comparing anesthesiologists of different level of expertise. The investigators hypothesize a substantial to almost perfect agreement in the intra- and interrater reliability of the antral cross-sectional area among raters in term pregnant patients scheduled for elective cesarean delivery.

Study Overview

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

• Study Type: Interventional
• Enrollment (Actual): 30
• Phase: Not Applicable

Contacts and Locations

Study Locations

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

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• non-laboring term pregnant women scheduled for cesarean delivery under neuraxial anesthesia
• ≥37 weeks gestational age
• ≥18 years of age
• ASA physical status II-III
• weight 50 to 120 kg
• height ≥150 cm
• ability to understand the rationale of the study evaluations.

Exclusion Criteria:

• multiple pregnancy
• known (reported by the study subject) anomalous anatomy of the upper gastrointestinal tract
• previous surgical procedures on the esophagus, stomach or upper abdomen
• patients not following our institutional fasting instructions (8 hours after a meal and 2 hours for clear liquids)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Gastric Ultrasound; Ultrasound measurements of the antrum will be recorded.	Device: Ultrasound; The gastric antrum will be scanned using ultrasound.; Other Names: Gastric Ultrasound

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Antral cross-sectional area (supine position)	The cross-sectional area (in centimeters squared) of the antrum will be measured with the patient in supine position, using the ultrasound machine. Measurements will be done 3 times, by 2 investigators.	5 minutes
Antral cross-sectional area (right lateral decubitus)	The cross-sectional area (in centimeters squared) of the antrum will be measured with the patient in right lateral decubitus position, using the ultrasound machine. Measurements will be done 3 times, by 2 investigators.	5 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Intra-rater reliability calculation	Intra-rater reliability will be calculated using the 3 measurements, for each rater.	5 minutes
Inter-rater reliability calculation	Inter-rater reliability will be calculated using the 3 measurements, between raters.	5 minutes
Grading of stomach contents	Grading scale: grade 0 means no gastric contents are visualized in supine and the right lateral decubitus, grade 1 means gastric contents are visualized in right lateral decubitus but not in supine decubitus, and grade 2 means gastric contents are visualized in both positions	5 minutes
Gastric volume (supine position)	Gastric volume (ml) will be estimated using the antral cross-sectional area obtained with the patient in supine position	5 minutes
Gastric volume (right lateral decubitus)	Gastric volume (ml) will be estimated using the antral cross-sectional area obtained with the patient in right lateral decubitus.	5 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 (Actual): July 20, 2023
• Primary Completion (Actual): October 30, 2023
• Study Completion (Actual): October 30, 2023

Study Registration Dates

• First Submitted: June 27, 2023
• First Submitted That Met QC Criteria: July 6, 2023
• First Posted (Actual): July 14, 2023

Study Record Updates

• Last Update Posted (Actual): February 23, 2024
• Last Update Submitted That Met QC Criteria: February 22, 2024
• Last Verified: February 1, 2024

More Information

Terms related to this study

• Keywords: Gastric Ultrasound
• Additional Relevant MeSH Terms: Digestive System Diseases; Pathologic Processes; Respiratory Tract Diseases; Respiration Disorders; Gastrointestinal Diseases; Esophageal Motility Disorders; Deglutition Disorders; Esophageal Diseases; Gastroesophageal Reflux; Laryngopharyngeal Reflux; Respiratory Aspiration; Respiratory Aspiration of Gastric Contents
• Other Study ID Numbers: 23-02

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No