Semaglutide and related drugs for weight loss have co-opted bariatric medicine in recent months. They have also raised serious questions for hospital-based clinicians who wonder whether the drugs may pose risks to surgery patients undergoing anesthesia.
Holding Ozempic (semaglutide) before elective surgery — and if so, for how long — remains largely a judgment call at this point. Official guidance on best practices has not yet caught up to surging popularity of this and other glucagon-like peptide-1 (GLP-1) agonists for weight loss.
Ozempic is indicated for treating type 2 diabetes but also is prescribed off-label for weight loss. Other GLP-1 agents from Novo Nordisk, Wegovy (semaglutide) and Saxenda (liraglutide) injections, are FDA-approved for weight loss. These medications work by decreasing hunger and lowering how much people eat. Semaglutide also is available as a once-daily tablet for type 2 diabetes (Rybelsus).
The American Society of Anesthesiologists (ASA) has been working on guidance on the drugs for the past 3 weeks. "It's a really hot issue now. We are getting emails from our members looking for guidance," ASA president Michael Champeau, MD, told Medscape Medical News.
But despite the interest in how the medications might affect surgery patients and interact with anesthesia, relatively little evidence exists in the literature beyond case studies. So the society is not issuing official recommendations at this point.
"We're going to just be calling it 'guidance' for right now because of the paucity of the scientific literature," said Champeau, adjunct clinical professor of anesthesiology, perioperative, and pain medicine at Stanford University in Palo Alto, California. "It's probably not going to have words like 'must; it will probably have words like 'should' or 'should consider.' "
The ASA guidance could be out in written form as early as next week, Champeau added.
Meanwhile, whether physicians should advise stopping these medications 24 hours, 48 hours, or up to 2 weeks before surgery remains unknown.
In search of some consensus, John Shields, MD, an orthopedic surgeon at Atrium Health Wake Forest Baptist Davie Medical Center in Bermuda Run, N.C., asked colleagues on #MedTwitter:
Because a full stomach can interfere with anesthesia, clinicians often advise people to stop eating and drinking 12-24 hours before elective procedures (NPO). In the case of once-weekly GLP-1 injections, which can slow gastric emptying, the optimal timeframe remains an open question. The main concern is aspiration, where a patient actively vomits while under anesthesia or their stomach contents passively come back up.
Shields' Twitter post garnered significant reaction and comments. Within 4 days, the post was retweeted 30 times and received 72 replies and comments. Shields noted the general consensus was to hold semaglutide for 1-2 weeks before a procedure. Other suggestions included recommending a liquid diet only for 24-48 hours before surgery, recommending an NPO protocol 24-36 hours in advance, or adjusting the weekly injection so the last dose is taken 5-6 days before surgery.
Anesthesiologist Cliff Gevirtz, MD, has encountered only a few surgical patients so far taking a GLP-1 for weight loss. "And thankfully no aspiration," added Gevirtz, clinical director of office-based ambulatory anesthesia services at Somnia Anesthesia in Harrison, New York.
To minimize risk, some physicians will perform an ultrasound scan to assess the contents of the stomach. If surgery is elective in a patient with a full stomach, the procedure can get postponed. Another option is to proceed with the case but treat the patient as anesthesiologists approach an emergency procedure. To be safe, many will treat the case as if the patient has a full stomach.
Gevirtz said he would treat the patient as a 'full stomach' and perform a rapid sequence induction with cricoid pressure. He would then extubate the patient once laryngeal reflexes return.
A rapid-sequence induction involves giving the medicine that makes a patient go to sleep, giving another medicine that paralyzes them quickly, then inserting a breathing tube — all within about 30 seconds. Cricoid pressure involves pushing on the neck during intubation to try to seal off the top of the esophagus and again minimize the chances of food coming back up.
Giving metoclopramide 30 minutes before surgery is another option, Gevirtz said. Metoclopramide can hasten the emptying of stomach contents. Administration in advance is important because waiting for the drug to work can prolong time in the operating room.
Is holding semaglutide before surgery a relevant clinical question? "Yes, very much so," said Ronnie Fass, MD, a gastroenterologist and the division director of gastroenterology and hepatology and the medical director of the Digestive Health Center at The MetroHealth System in Cleveland.
Fass recommended different strategies based on the semaglutide indication. Currently, clinicians at MetroHealth instruct patients to discontinue diabetic medications the day of surgery. For those who take semaglutide for diabetes, and because the medication is taken once a week, "there is growing discussion among surgeons that the medication should not be stopped prior to surgery. This is to ensure that patients' diabetes is well controlled before and during surgery," Fass said.
In patients taking semaglutide for weight loss only, "there is no clear answer at this point," he said.
Fass said the question is complicated by the fact that the medication is taken once a week. "It brings up important questions about the use of the medication during surgery, which may increase the likelihood of side effects in general and for certain types of surgery. Personally, if a patient is taking [semaglutide] for weight loss only, I would consider stopping the medication before surgery."
The ASA was able to act quickly because it already had an expert task force review how long people should fast before surgery last year — before the explosion in popularity of the GLP-1 agonists.
Although still a work in progress, Champeau offered Medscape readers "a peek" at the recommendations. "The guidance is going to look at how far in advance the drugs should be stopped, rather than looking at making people fast even longer" before surgery, he said. "There's just no data on that latter question."
Damian McNamara is a staff journalist based in Miami. He covers a wide range of medical specialties, including infectious diseases, gastroenterology and critical care. Follow Damian on Twitter: @MedReporter.