Casey A. Murphy, M.D., F.A.A.P.M.R., D.A.A.P.M.

Introduction: This article will review interactions of a new diabetic weight loss drug with
monitored anesthesia (MAC) care during interventional pain management procedures.
Procedures across the country are being postponed due to the risk of aspiration associated with
semaglutide in MAC cases.

Semaglutide, was first approved by the Food and Drug Administration (FDA) in the United
States in 2017 for use in the treatment of type 2 diabetes. In 2021, the FDA extended indications
of this medication for weight loss. Semaglutide is a glucagon-like peptide-1 (GLP-1) receptor
agonist that increases glucose-dependent insulin secretion, decreases inappropriate glucagon
secretion, and slows gastric emptying. It also acts in the areas of the brain involved in regulation
of appetite and caloric intake. It can be given by mouth daily or subcutaneous weekly.
In 2021, a randomized controlled trial was conducted in obese patients, that documented a
reduction in body weight of 34-pounds from baseline to week 68 for participants in the
semaglutide group. 1 The most common adverse reactions are gastrointestinal effects which
include abdominal pain, constipation, diarrhea, nausea, and vomiting.

Many interventional pain procedures done in the United States are done in conjunction with
monitored anesthesia care (MAC). There is a low incidence of pulmonary aspiration during
anesthesia; this equates to one in every 2000–3000 interventional procedures requiring
anesthesia. 2  Current guidelines recommend preoperative fasting of 2 h for clears fluids and 6–8 h
for solids and fluids with residue; 3 some institutions require a 12 hour fast of solid food and
colored fluids. At risk patients for aspiration include diabetes, previous foregut surgery, elderly,
and obese patients. Little is known as to bridging long-acting to short-acting diabetic medications
for procedures using anesthesia.

A retrospective study was done in 2023. 4 Of the 886 esophagogastroduodenoscopy procedures
performed, 404 (33 in the semglutide group (SG) and 371 in the non-semaglutide group (NSG))
were included in the final analysis. Increased residual gastric contents (RGC) was observed in 27
(6.7%) participants, 8 (24.2%) in the SG and 19 (5.1%) in the NSG ( p < 0.001). Semaglutide use
and the presence of preoperative digestive symptoms including nausea, vomiting, dyspepsia, and
abdominal distension were associated with increased RGC. In the SG group, the mean time of
preoperative semaglutide interruption in patients with and without increased RGC was 10.5 ± 5.5
and 10.2 ± 5.6 days, respectively. There was no relationship between semaglutide use and the
volume of RGC found on esophagogastroduodenoscopy. Only one case in the semaglutide group
reported pulmonary aspiration; this was a 63-year-old man, with BMI of 37.7, a history of
hypertension and previous gastric bypass. His last preoperative use of semaglutide was 11 days
prior to upper endoscopy. His fasting interval for both clear fluids and solids was 12.4 hr. The
absence of ongoing digestive symptoms in patients on regular use of semaglutide was associated
with a lower, albeit still elevated, risk of increased residual gastric content (RGC). 4

In another case report, a 42-yr-old patient with Barrett's esophagus underwent repeated upper
gastrointestinal endoscopy and ablation of dysplastic mucosa. Two months earlier, the patient
had started weekly injections of semaglutide for weight loss. Despite having fasted for 18 hours,
and differing from the findings of prior procedures, endoscopy revealed substantial gastric
content, which had to be suctioned. 5
There is another important note to consider in patients with chronic pain and GLP-1 medications.
Semaglutide slows gastric emptying, which may alter the absorption of other medications. It
should be noted that patients being treated for chronic pain with salicylates and selective
serotonin reuptake inhibitors are at significant risk for medication interactions that may lead to
enhanced hypoglycemic effect of agents with blood glucose lowering properties.


It seems that there is a slightly higher risk of aspiration associated with interventional procedures
requiring anesthesia when taking semaglutide; this risk is increased when patients report
gastrointestinal issues such as gastric reflux, abdominal pain, constipation, diarrhea, nausea, and
vomiting. Clear recommendations on “if” and “when” semaglutide should be stopped before
anesthesia is unknown, but similarly to situations where patients take anticoagulants as part of
their regimen of chronic pain or for cardiac or stroke prophylaxis; the decision should be made
based on discussions between the patient, nurse, and physician about the risks of stopping or
continuing semaglutide.

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RF; STEP 1 Study Group. Once-Weekly Semaglutide in Adults with Overweight or
Obesity. N Engl J Med. 2021 Mar 18;384(11):989-1002. doi: 10.1056/NEJMoa2032183.
Epub 2021 Feb 10. PMID: 33567185.
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the risk of pulmonary aspiration: application to healthy patients undergoing elective
procedures. Anesthesiology 2017; 126: pp. 376-393.
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Santos LB, Ho AM, Nersessian RSF, Lima FLM, Silva MV, Mizubuti GB. Relationship
between perioperative semaglutide use and residual gastric content: A retrospective
analysis of patients undergoing elective upper endoscopy. J Clin Anesth. 2023
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pulmonary aspiration: a case report. Can J Anaesth. 2023 Mar 28. English. doi:
10.1007/s12630-023-02440-3. Epub ahead of print. PMID: 36977934.