Clinical Trial Details
— Status: Recruiting
Administrative data
| NCT number |
NCT06420739 |
| Other study ID # |
23-5873 |
| Secondary ID |
|
| Status |
Recruiting |
| Phase |
|
| First received |
|
| Last updated |
|
| Start date |
March 25, 2024 |
| Est. completion date |
March 2026 |
Study information
| Verified date |
May 2024 |
| Source |
University Health Network, Toronto |
| Contact |
Anahi Perlas, MD FRCPC |
| Phone |
4166035800 |
| Email |
anahi.perlas[@]uhn.ca |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Observational
|
Clinical Trial Summary
The primary goal of this study is to evaluate the incidence of "full stomach" in fasting
elective surgical patients on Semaglutide medication. The other goals are to study the impact
of the time interval since the last dose of the medication on the incidence of full stomach
and to develop evidence-based recommendations for the perioperative management of these
patients.
Description:
Pulmonary aspiration of gastric contents has long been recognized as a threat to anesthesia
patient safety. Most elective surgical patients, however, are considered to be at low risk
for this complication provided they abstain from eating solid food for at least 8 hours prior
to anesthesia and for clear fluids for at least 2 hours. The recent introduction of GLP-1
agonists (such as Semaglutide), a new class of drugs for the treatment of diabetes and weight
loss, has challenged the status quo, and is posing a new threat to perioperative patient
safety.There are recent reports of aspiration of large amounts of particulate undigested food
in the perioperative period on patients taking Semaglutide despite prolonged fasting of over
12 hours, one of those cases happening at the UHN.This is of great concern given the
explosive increase in use of these medications globally.In the month of June 2023, three
North American anesthesiology societies (the Canadian Anesthesiologists' Society, the
American Society of Anesthesiologists and the Anesthesia Patient Safety Foundation) have
raised the alert regarding an increased risk of aspiration under anesthesia while on these
drugs.Given the long half-life of up to 7 days, a true reduction of risk would necessitate
holding these drugs preoperatively for longer periods than are usually feasible.
Management strategies recommended to date include treating every patient on Semaglutide as if
they have a 'full stomach", avoiding general anesthesia if possible and even considering
surgical cancellation if the patient presents symptoms such as nausea and vomiting, which are
common while on these medications. While these recommendations stand to reason, they are
over-arching, targeted to all patients and could result in unnecessary surgical cancellations
or invasive procedures (such as nasogastric tube insertion, endotracheal intubation and rapid
sequence induction) which have their own set of risks.
This timely study addresses the current knowledge gap and a recently identified threat to
perioperative patient safety that has been highlighted by three major anesthesiology
societies in the past 2-3 months. Our team at the UHN is uniquely positioned to shed some
light into these pressing questions and develop management recommendations that optimize
safety while avoiding unnecessary surgical cancellations and targeting invasive procedures
for airway management only to those patients that really need them.
Our group has previously developed and validated a simple, non-invasive bedside ultrasound
test that can differentiate a safe "empty stomach" from a "full stomach" that may pose an
increased risk of aspiration under anesthesia. The investigators have validated this bedside
test in the adult, pediatric, obstetric and morbidly obese populations.
Hypothesis:
Patients on Semaglutide will have an increased incidence of full stomach to at least 10%,
compared to a baseline of 5%, a difference that the investigators consider clinically
significant.
Study design:
This is a prospective cohort study.
Study population:
The investigators propose to study a cohort of 100 patients undergoing elective surgery while
under treatment with Semaglutide for either diabetes or for losing weight.
Patients who are on Semaglutide for at least a month will be identified, screened for
eligibility, and invited to participate in this study.All identified patients will be given
standard pre-operative fasting instructions as per current institutional practice for
elective surgical patients (a minimum of 8 hours of fasting for solid food and 4 hours for
clear fluids).
A bedside gastric ultrasound examination will be performed using a portable ultrasound unit
and a curvilinear low-frequency probe with abdominal settings. The exam will be done in two
positions (supine and right lateral decubitus). The gastric antrum will be identified in a
sagittal plane in the epigastric area between the left lobe of the liver anteriorly and the
pancreas and aorta posteriorly. The type of gastric content (nothing, clear fluid or solid)
will be documented based on qualitative findings.
If clear fluid is present our mathematical model will be used to estimate the volume based on
a cross-sectional area of the gastric antrum:
(Volume (ml) = 27.0 + 14.6 x CSA (cm2) - 1.28x age (year).11
A stomach will be considered:
1. "empty" and consistent with "low aspiration risk" if the antrum appears completely empty
in both supine and right lateral decubitus position (Grade 0 antrum) or there is clear
fluid with a volume < 1.5 mL/Kg which is consistent with a low-risk situation.
2. "full" or at risk of aspiration if there is any amount of solid content or clear fluid
with a volume, > 1.5 mL/Kg.
The result of the gastric ultrasound study will be shared with the attending
anaesthesiologist in charge of every patient who will be free to establish what they consider
the safest management plan based on their clinical judgement and the ultrasound results. The
surgical timing (on time, delayed or cancelled), the type of anaesthetic used, and the airway
management strategies will be documented. Changes in anaesthetic management from the a priori
plan will be documented. Any episodes of regurgitation or aspiration in the perioperative
period will be documented. Information on anaesthetic technique, airway management and the
incidence of regurgitation and aspiration throughout the intraoperative period will be
recorded.
