Gastric Ultrasound in Pregnant Women at Term

Study Overview
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Brief Summary
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Solid food or fluid residue in the stomach is always a major concern when patients need 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 is not observed. The aspiration of the stomach contents into one's lungs can lead to serious complications (such as severe respiratory failure). Information from a bedside ultrasound assessment of the stomach may be a very useful tool to decide whether or not it's safe to proceed, cancel or delay a surgical procedure.

Detailed Description
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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. A bedside ultrasound assessment fo the status of the gastric content would be of great value for the clinician. This technique has recently been shown very promising in non-pregnant patients and it is important to study its feasibility in the pregnant population. In this study, patients fast overnight and are randomized to the following groups: empty, fluid (250 mL of apple juice before scanning) or solid (full breakfast). Their gastric contents are then assessed by 3 different anesthesiologists, using ultrasound. At the end of the scanning, the true stomach contents are revealed. The ability of the assessors to accurately predict stomach contents, as well as the inter-observer agreement, will be examined.

Official Title
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Qualitative Ultrasound Assessment of the Gastric Content of Pregnant Women at Term

Conditions
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Respiratory Aspiration, Pregnancy

Intervention / Treatment
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* Other: Empty
* Other: Fluid
* Other: Solid


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Volunteer non-laboring pregnant women >32 weeks gestation 18 years or older ASA status I-III Weigh between 50 and 120kg Height at least 150cm or taller Written informed consent Exclusion Criteria: Known pre-existing abnormal anatomy of the upper GI tract Protocol violation

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 50 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Empty stomach<br>Patients have fasted for 8 hours. | Other: Empty<br>* overnight fast<br>|
| Other: Fluid<br>Patients have fasted for 8 hours, followed by the consumption of 250mL of apple juice. | Other: Fluid<br>* 250mL apple juice<br>|
| Other: Solid<br>Patients have fasted for 8 hours, followed by the consumption of their breakfast. | Other: Solid<br>* breakfast<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Reliability of the ultrasonographic diagnosis of the gastric status | Three physicians trained in gastric ultrasound will be blinded to the treatment group the patient was in, perform an ultrasound, and try to guess whether the patient has an empty stomach, consumed fluids only, or consumed a full meal. | 30 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Inter-observer agreement of gastric content diagnosis |  | 30 minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Pregnancy, Respiratory aspiration, Gastric contents, Ultrasound