Gastric RetentionRESIDUALNCT06500143
Residual Gastric Content After Holding of Glucagon-like Peptide-1 Receptor Agonists Before Elective Surgery
An observational study of Gastric Retention, run by Ciusss de L'Est de l'Île de Montréal at 1 site in Canada.
Trial summary
Glucagon-like peptide-1 agonists (GLP-1RA) are a family of medications used for diabetes and weight loss. One of their effect is to slow down stomach emptying. The goal of this study is to evaluate the effect of GLP-1RA on the effectiveness of fasting before a scheduled surgery. Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Gastric Retention
- What is being tested?
- Gastric ultrasound
- How many people
- 94 participants
- Where
- 1 siteCanada
- Study dates
- 9 Oct 2024to 28 Feb 2025
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Study population: Adult population undergoing elective surgery
Who may be able to join
- American Society of Anesthesiologists (ASA) class 1-4 patients
- Age ≥ 18 years old
- Fasted state (2 hours for clear liquids, 6 hours for solids)
- Elective surgery
- Last dose of once-weekly semaglutide or dulaglutide 7 days or more before surgery (for GLP-1RA group)
Who cannot join
- Last dose of GLP-1RA less than 7 days before surgery
- Inability to lay on the right-side for ultrasound
- Pregnancy
- History of gastric surgery or large hiatal hernia
Trial locations and contacts
1 site in 1 country.
About this study
Official title: The RESIDUAL Study : Residual Gastric Content After Holding of Glucagon-like Peptide-1 Receptor Agonists Before Elective Surgery: a Cross-sectional Study
Glucagon-like peptide-1 agonists (GLP-1RA) are a family of medications used for diabetes and weight loss. One of their effect is to slow down stomach emptying. The goal of this study is to evaluate the effect of GLP-1RA on the effectiveness of fasting before a scheduled surgery.
The question it aims to answer is: does this kind of medication increase the risk of having food or too much liquid in the stomach before a scheduled surgery, even if the minimum 6 hour fast is done?
Read more
For this project, researchers will use gastric ultrasound to compare participants already taking one of these medications as part of their home treatment to participants who are not taking them. Gastric ultrasound is a simple bedside exam using an echography machine that takes less than 5 minutes to do.
Participants will:
-Have a gastric ultrasound performed on them before their surgery
Read the detailed description
Background: Glucagon-like peptide-1 receptor agonists (GLP-1RA) are glucose-lowering drugs that act through three mechanisms: stimulation of insulin secretion, inhibition of glucagon secretion and decrease of gastric emptying. The GLP-1RA are now an important part of glycemic control in type 2 diabetes mellitus (T2DM). Recently, GLP-1 RA have received approval for weight loss, expanding their use in overweight or obese non-diabetic patients.The effect of GLP-1RA on decreased gastric emptying has long been established but he clinical implication of this in the periprocedural setting is uncertain. Recent guidelines recommend holding the weekly-dosed for at least a week before elective surgery. Considering the extended half-lives of once-weekly GLP-1RA (approximately 6 days for semaglutide and 5 days for dulaglutide), it is unclear if following those guidelines is sufficient to make sure patients are not at high risk of aspiration
Hypothesis: This study will compare ultrasound-assessed residual gastric content (RGC) between once-weekly GLP-1RA users that stopped their medication for 7 days or more before elective surgery and patients not taking GLP-1RA. The investigators hypothesized that even with appropriate holding of GLP-1RA, those patients may have increased RGC and be at higher risk of aspiration.
Objectives:
Primary objective:
- To investigate the relation between GLP-1RA use and increased RGC
Secondary objectives:
- To assess the relation between the number of days since the last dose of GLP-1RA and increased RGC
- To assess the relation between the dose of GLP-1RA and RGC
Exploratory objectives:
- To explore the relation between other known risk factors of gastroparesis and increased RGC
- To explore the relation between the time since the last oral intake and increased RGC
Methods : A gastric ultrasound (GUS)will be performed on all patients to assess RGC using a published validated and reproductible method used in recent trials. The acquisition of images will be performed by a blinded anesthesiologist or anesthesiology resident using a dedicated ultrasound machine. The images will be saved and reviewed by another blinded trained anesthesiologist.
Significance/importance: The results of this study could challenge the actual recommendations for GLP-1RA stoppage before surgery and help improve perioperative care for patients taking GLP-1RA.
- Conditions
- Gastric Retention
- Being tested
- Gastric ultrasound
- Keywords
- glucagon-like peptide 1, gastric ultrasound, surgery, diabetes, weight loss, increased residual gastric content, semaglutide, dulaglutide
- Medical subject headings
- Diabetes Mellitus, Weight Loss
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Gastric ultrasoundDiagnostic test
Using a curved array low-frequency abdominal probe (2-5 MHz) with abdominal presets and with the patient in right lateral decubitus position, the gastric antrum will be identified in a standardized plane at the level of the aorta. The stomach will be considered empty if the antrum appears flat or round with anterior and posterior walls collapsed. Normal gastric secretions and clear fluids have an anechoic or hypoechoic aspect on ultrasonography. Solid or thick fluids have a hyperechoic aspect and can create "ring-down" artifacts blurring gastric content, its posterior wall, the pancreas and the aorta. Following qualitative examination, quantitative assessment will be performed if there is presence of clear fluids. The cross-sectional area (CSA) of the antrum will be measured with three measurements to calculate a mean value.
| Study group | Role | What they receive |
|---|---|---|
| GLP-1RA agonists users | Participants presenting for elective surgery and taking once-weekly semaglutide or dulaglutide as part of their usual treatment with the last dose at least 7 days before surgery Receives: Diagnostic Test: Gastric ultrasound | |
| Control group | Participants presenting for elective surgery and not taking semaglutide or dulaglutide Receives: Diagnostic Test: Gastric ultrasound |
What is being measured
The primary outcome is the main question the study is designed to answer.
Increased residual gastric content
The primary endpoint will be the prevalence of increased residual gastric content defined by the presence of any of the following:
- Solid or thick fluid content on gastric ultrasound
- Content of more than 1.5 mL/kg of clear fluids on gastric ultrasound using the following formula : Gastric volume (mL) = 27 + [14.6 × right lateral cross-sectional area (in cm2)] - [1.28 × age (in years)]
Measured: Preoperative (day of surgery)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted15 Jul 2024
- Study start9 Oct 2024
- Primary completion28 Feb 2025
- Study completion28 Feb 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Gastric RetentionStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Other
- Time perspective
- Cross-sectional
- Enrolment
- 94 participants (actual)
Sponsor and investigators
- Lead sponsor
- Ciusss de L'Est de l'Île de Montréal
- Sponsor type
- University, hospital or other
- Collaborators
- Institut de Cardiologie de Montréal
- Responsible party
- Sponsor
- Investigators
- Louis Morisson, MD, MSc, Principal investigator, CIUSS de l'Est de l'Île de Montréal
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06500143
- Sponsor's protocol ID
- MP-12-2025-3794
- Acronym
- RESIDUAL
- Status last verified
- Dec 2025
- First submitted
- 8 Jul 2024
- Last updated
- 16 Jan 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Publications
Boudreau C, Couture M, Rousseau-Saine N, Laferriere-Langlois P, Roy-Renaud E, Burey J, Raymond M, Denault A, Morisson L. Residual gastric content after holding of glucagon-like peptide-1 receptor agonists before elective surgery: a cross-sectional study - the RESIDUAL study. BMC Anesthesiol. 2026 Jun 10. doi: 10.1186/s12871-026-03999-2. Online ahead of print.
PubMed 42265610
Study at a glance
From the registry record, last updated by the sponsor on 16 Jan 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The RESIDUAL Study : Residual Gastric Content After Holding of Glucagon-like Peptide-1 Receptor Agonists Before Elective Surgery: a Cross-sectional Study
- ClinicalTrials.gov ID
- NCT06500143
- Acronym / sponsor ID
- RESIDUAL / MP-12-2025-3794
- Conditions
- Gastric Retention
- Keywords
- glucagon-like peptide 1, gastric ultrasound, surgery, diabetes, weight loss, increased residual gastric content, semaglutide, dulaglutide
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 94 participants (actual)
- Lead sponsor
- Ciusss de L'Est de l'Île de MontréalUniversity, hospital or other
- Collaborators
- Institut de Cardiologie de Montréal
- Study start
- 9 Oct 2024 (actual)
- Primary completion
- 28 Feb 2025 (actual)
- Study completion
- 28 Feb 2025 (actual)
- First posted
- 15 Jul 2024 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Glucagon-like peptide-1 agonists (GLP-1RA) are a family of medications used for diabetes and weight loss. One of their effect is to slow down stomach emptying. The goal of this study is to evaluate the effect of GLP-1RA on the effectiveness of fasting before a scheduled surgery.
The question it aims to answer is: does this kind of medication increase the risk of having food or too much liquid in the stomach before a scheduled surgery, even if the minimum 6 hour fast is done?
For this project, researchers will use gastric ultrasound to compare participants already taking one of these medications as part of their home treatment to participants who are not taking them. Gastric ultrasound is a simple bedside exam using an echography machine that takes less than 5 minutes to do.
Participants will:
-Have a gastric ultrasound performed on them before their surgery
Detailed description
Background: Glucagon-like peptide-1 receptor agonists (GLP-1RA) are glucose-lowering drugs that act through three mechanisms: stimulation of insulin secretion, inhibition of glucagon secretion and decrease of gastric emptying. The GLP-1RA are now an important part of glycemic control in type 2 diabetes mellitus (T2DM). Recently, GLP-1 RA have received approval for weight loss, expanding their use in overweight or obese non-diabetic patients.The effect of GLP-1RA on decreased gastric emptying has long been established but he clinical implication of this in the periprocedural setting is uncertain. Recent guidelines recommend holding the weekly-dosed for at least a week before elective surgery. Considering the extended half-lives of once-weekly GLP-1RA (approximately 6 days for semaglutide and 5 days for dulaglutide), it is unclear if following those guidelines is sufficient to make sure patients are not at high risk of aspiration
Hypothesis: This study will compare ultrasound-assessed residual gastric content (RGC) between once-weekly GLP-1RA users that stopped their medication for 7 days or more before elective surgery and patients not taking GLP-1RA. The investigators hypothesized that even with appropriate holding of GLP-1RA, those patients may have increased RGC and be at higher risk of aspiration.
Objectives:
Primary objective:
- To investigate the relation between GLP-1RA use and increased RGC
Secondary objectives:
- To assess the relation between the number of days since the last dose of GLP-1RA and increased RGC
- To assess the relation between the dose of GLP-1RA and RGC
Exploratory objectives:
- To explore the relation between other known risk factors of gastroparesis and increased RGC
- To explore the relation between the time since the last oral intake and increased RGC
Methods : A gastric ultrasound (GUS)will be performed on all patients to assess RGC using a published validated and reproductible method used in recent trials. The acquisition of images will be performed by a blinded anesthesiologist or anesthesiology resident using a dedicated ultrasound machine. The images will be saved and reviewed by another blinded trained anesthesiologist.
Significance/importance: The results of this study could challenge the actual recommendations for GLP-1RA stoppage before surgery and help improve perioperative care for patients taking GLP-1RA.
Study design
- Observational model
- Other
- Time perspective
- Cross-sectional
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| GLP-1RA agonists users | – | Diagnostic Test: Gastric ultrasoundParticipants presenting for elective surgery and taking once-weekly semaglutide or dulaglutide as part of their usual treatment with the last dose at least 7 days before surgery |
| Control group | – | Diagnostic Test: Gastric ultrasoundParticipants presenting for elective surgery and not taking semaglutide or dulaglutide |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
- Study population
- Adult population undergoing elective surgery
Key inclusion criteria (5 listed)
- American Society of Anesthesiologists (ASA) class 1-4 patients
- Age ≥ 18 years old
- Fasted state (2 hours for clear liquids, 6 hours for solids)
- Elective surgery
- Last dose of once-weekly semaglutide or dulaglutide 7 days or more before surgery (for GLP-1RA group)
Key exclusion criteria (4 listed)
- Last dose of GLP-1RA less than 7 days before surgery
- Inability to lay on the right-side for ultrasound
- Pregnancy
- History of gastric surgery or large hiatal hernia
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Gastric ultrasoundUsing a curved array low-frequency abdominal probe (2-5 MHz) with abdominal presets and with the patient in right lateral decubitus position, the gastric antrum will be identified in a standardized plane at the level of the aorta. The stomach will be considered empty if the antrum appears flat or round with anterior and posterior walls collapsed. Normal gastric secretions and clear fluids have an anechoic or hypoechoic aspect on ultrasonography. Solid or thick fluids have a hyperechoic aspect and can create "ring-down" artifacts blurring gastric content, its posterior wall, the pancreas and the aorta. Following qualitative examination, quantitative assessment will be performed if there is presence of clear fluids. The cross-sectional area (CSA) of the antrum will be measured with three measurements to calculate a mean value. | Diagnostic test | Control group, GLP-1RA agonists users |
Primary outcome
Increased residual gastric content
Time frame: Preoperative (day of surgery)
The primary endpoint will be the prevalence of increased residual gastric content defined by the presence of any of the following: * Solid or thick fluid content on gastric ultrasound * Content of more than 1.5 mL/kg of clear fluids on gastric ultrasound using the following formula : Gastric volume (mL) = 27 + [14.6 × right lateral cross-sectional area (in cm2)] - [1.28 × age (in years)]
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 16 Jan 2026.
- Derived from this study: PubMed 42265610Boudreau C, Couture M, Rousseau-Saine N, Laferriere-Langlois P, Roy-Renaud E, Burey J, Raymond M, Denault A, Morisson L. Residual gastric content after holding of glucagon-like peptide-1 receptor agonists before elective surgery: a cross-sectional study - the RESIDUAL study. BMC Anesthesiol. 2026 Jun 10. doi: 10.1186/s12871-026-03999-2. Online ahead of print.
Related trials for Gastric Retention
RecruitingObservational study
Development and Validation of a Risk Prediction Model for Gastric Retention in Patients Undergoing Sedated Gastroscopy
Gastric Cancer Stage, Esophageal Cancer
RecruitingObservational study
GLP1 Fasting Status and Gastric Retention Using Gastric Ultrasound
Gastric Retention
Recruiting
The PRE-VAIL Study
ARDS (Moderate or Severe), Prone Position
Not yet recruitingObservational study
Impact of Discontinuing GLP-1 Receptor Agonists for Two Weeks Prior to Upper Endoscopy on the Risk of Gastric Retention
Gastric Retention
Not yet recruitingObservational study
Impact of Neuropathy on the Risk of Semaglutide-Induced Gastric Retention
Gastric Retention
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Louis Morisson, MD, MSc principal investigator
CIUSS de l'Est de l'Île de Montréal
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Gastric Retention, run by Ciusss de L'Est de l'Île de Montréal at 1 site in Canada.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 4 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 16 Jan 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Canada. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Increased residual gastric content (time frame: Preoperative (day of surgery)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT06500143, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 16 Jan 2026.