Updated fasting guidelines

[nimbus]

Glad they finally addressed gum. Hopefully it will save some phone calls from preop. I’ve always ignored it.

2023 American Society of Anesthesiologists Practice Guidelines for Preoperative Fasting: Carbohydrate-containing Clear Liquids with or without Protein, Chewing Gum, and Pediatric Fasting Duration—A Modular Update of the 2017 American Society of Anest

These practice guidelines are a modular update of the “Practice guidelines for preoperative fasting and the use of pharmacologic agents to reduce the risk of pulmonary aspiration: Application to healthy patients undergoing elective procedures.” The guidance focuses on topics not addressed in the...

pubs.asahq.org

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[Arch Guillotti]

I always just had them spit it out although I have seen cases delayed up to 6 hours for this.

Maybe next they will address dip and chewing tobacco.

 

[dabears505]

It's interesting they write that these simple carbs are useful 2 hrs before and there are many detrimental effects of prolonged fasting. It seems to me more and more people are thinking the opposite.

 

[Beeftenderloin]

Would have been nice to get some guidance on periop fasting for the new GLP1 meds. Ozempic/semaglutide is the one that’s been all over the news lately, but look for mounjaro/tirzepatide coming down the pike. They’re becoming extremely popular for weight loss, so much so that people can’t actually find ozempic anywhere to fill for their diabetes.

They’re both once weekly injections that work by increasing feelings of satiety and markedly delaying gastric emptying. But I haven’t seen any guidance about how long/how much gastric emptying is delayed, just that it is. Half lives are 7 days and 5 days respectively. So in terms of holding the drug, patients would need to stop it about a month before surgery, which isn’t necessarily always possible.

Per forums on some other sites, some groups are going as far as telling people on the drug to be on clears only the day before, then true NPO after midnight. Others are just RSIing everyone who’s on it, not doing MACs, even after 8hrs NPO. Has anyone’s group/hospital/system developed a formal policy around these drugs?

 

[Ashers]

I always just had them spit it out although I have seen cases delayed up to 6 hours for this.

Maybe next they will address dip and chewing tobacco.

I was just going to say that about tobacco.

I've had 2 patients chewing tobacco in preop once in residency and once as an attending. I delayed by 2 hours both times. In residency my attending and I surveyed multiple people to see what they would do, most said cancel, some said delay 8, 1 said do nothing, so we delayed 2 because it was 12/30 and deductibles. I honestly don't know what is right. The reasoning was decreased LES tone.

In residency, I had attendings delay cases for 8 hours with gum... I have them spit it out.

 

[Onefellswoop87]

I was just going to say that about tobacco.

I've had 2 patients chewing tobacco in preop once in residency and once as an attending. I delayed by 2 hours both times. In residency my attending and I surveyed multiple people to see what they would do, most said cancel, some said delay 8, 1 said do nothing, so we delayed 2 because it was 12/30 and deductibles. I honestly don't know what is right. The reasoning was decreased LES tone.

In residency, I had attendings delay cases for 8 hours with gum... I have them spit it out.

What’s the rationale to delaying? Same reason I’ve never delayed for gum, just have them spit it out. They aren’t “ingesting” anything. Chewing tobacco isn’t chewing and swallowing (well, a minority swallows dip spit and that is eff’ing gross).
They are swallowing their own saliva, not extra fluid. It’s tinged and flavored by the tobacco but it’s not like they are drinking extra volume.

I tried to look up what dip spit contains but can’t find any bored academic who published such a paper. A cup of dip is about 15-20 grams of carbohydrates. So a pinch is then 1 gram? Sounds negligible to stomach volume from a digestive perspective and effect on gastric emptying. For context, the CocaCola in front of me is 55 grams of carbohydrates.

I get it you said that you were resident when that happened, but these events always make me scratch my head

I bet the ASA didn’t include dip in their recommendations with gum because then one could argue that’s passive approval to use chewing tobacco before surgery.

 

[Ashers]

What’s the rationale to delaying? Same reason I’ve never delayed for gum, just have them spit it out. They aren’t “ingesting” anything. Chewing tobacco isn’t chewing and swallowing (well, a minority swallows dip spit and that is eff’ing gross).
They are swallowing their own saliva, not extra fluid. It’s tinged and flavored by the tobacco but it’s not like they are drinking extra volume.

I tried to look up what dip spit contains but can’t find any bored academic who published such a paper. A cup of dip is about 15-20 grams of carbohydrates. So a pinch is then 1 gram? Sounds negligible to stomach volume from a digestive perspective and effect on gastric emptying. For context, the CocaCola in front of me is 55 grams of carbohydrates.

I get it you said that you were resident when that happened, but these events always make me scratch my head

I bet the ASA didn’t include dip in their recommendations with gum because then one could argue that’s passive approval to use chewing tobacco before surgery.

The rationale was the effect on decreasing the lower esophageal sphincter tone. Some people swallow some, and if that crap got into the lungs... Like I said, I don't know what's right, but I wasn't going to risk it. I don't even remember what kind of case it was as an attending, I just remember it happened. As a resident, it was a total knee on 12/30; that one my attending wanted to cancel.

 

[Onefellswoop87]

The rationale was the effect on decreasing the lower esophageal sphincter tone. Some people swallow some, and if that crap got into the lungs... Like I said, I don't know what's right, but I wasn't going to risk it. I don't even remember what kind of case it was as an attending, I just remember it happened. As a resident, it was a total knee on 12/30; that one my attending wanted to cancel.

Thanks. I had no idea the LES was lowered by such a large degree (19-42%), though that is specifically quoted from studying nicotine patch.

But serious question - what do you do about the patient who smoked cigarettes or vaped with nicotine right before checking in?

Do you delay their induction? Where do you draw the line?

I personally don’t RSI everyone who has GERD (they probably have a degree of lessened LES compared to the rest of the population) unless they have active reflux symptoms or regurgitation. If their nicotine caused decreased LES caused symptoms, I’d delay or RSI if couldn’t delay.

Effects of transdermal nicotine on lower esophageal sphincter and esophageal motility - PubMed

Cigarette smoking has been shown to decrease lower esophageal sphincter pressure (LESP) by 19-42%. This decrease in LESP may be due to nicotine in the cigarette smoke or substances other than nicotine. The aim of this study was to evaluate the effects of a nicotine patch on esophageal motility...

pubmed.ncbi.nlm.nih.gov

 

[Ashers]

Thanks. I had no idea the LES was lowered by such a large degree (19-42%), though that is specifically quoted from studying nicotine patch.

But serious question - what do you do about the patient who smoked cigarettes or vaped with nicotine right before checking in?

Do you delay their induction? Where do you draw the line?

I personally don’t RSI everyone who has GERD (they probably have a degree of lessened LES compared to the rest of the population) unless they have active reflux symptoms or regurgitation. If their nicotine caused decreased LES caused symptoms, I’d delay or RSI if couldn’t delay.

Effects of transdermal nicotine on lower esophageal sphincter and esophageal motility - PubMed

Cigarette smoking has been shown to decrease lower esophageal sphincter pressure (LESP) by 19-42%. This decrease in LESP may be due to nicotine in the cigarette smoke or substances other than nicotine. The aim of this study was to evaluate the effects of a nicotine patch on esophageal motility...

pubmed.ncbi.nlm.nih.gov

These were patients chewing in the preop bay. There isn't a total equivalent since the saliva they may have swallowed won't be as gross as tobacco crap. But smoking preop and taking the patch off preop, usually is about a few hours before surgery. I've found most people even take fentanyl patches off before surgery, so I haven't run across it before.

 

[gator2886]

Would have been nice to get some guidance on periop fasting for the new GLP1 meds. Ozempic/semaglutide is the one that’s been all over the news lately, but look for mounjaro/tirzepatide coming down the pike. They’re becoming extremely popular for weight loss, so much so that people can’t actually find ozempic anywhere to fill for their diabetes.

They’re both once weekly injections that work by increasing feelings of satiety and markedly delaying gastric emptying. But I haven’t seen any guidance about how long/how much gastric emptying is delayed, just that it is. Half lives are 7 days and 5 days respectively. So in terms of holding the drug, patients would need to stop it about a month before surgery, which isn’t necessarily always possible.

Per forums on some other sites, some groups are going as far as telling people on the drug to be on clears only the day before, then true NPO after midnight. Others are just RSIing everyone who’s on it, not doing MACs, even after 8hrs NPO. Has anyone’s group/hospital/system developed a formal policy around these drugs?

We are considering changing fasting guidelines on GLP1 patients. We have seen and heard reports of undigested food coming up even with current NPO guidelines

 

[Hoya11]

We are considering changing fasting guidelines on GLP1 patients. We have seen and heard reports of undigested food coming up even with current NPO guidelines

Good to here your experience. It seems like everyone is on ozempic now for weight loss

 

[UBCmed09]

We are considering changing fasting guidelines on GLP1 patients. We have seen and heard reports of undigested food coming up even with current NPO guidelines

At our regional hospital here in Canada we've given direction to our preoperative nurses to instruct patients to hold semaglutide for at least 3 weeks whenever feasible (ie >= 3 half-lifes; still not optimal of course). Most of our patients are on semaglutide (and now seeing the odd one on tirzepatide) for weight loss, rather than diabetes management. That being said, we're uncertain what the impact on day-to-day glucose will be for diabetics if they were to stop their semaglutide (all other thing being equal, such as, say, being on metformin or some such). Unfortunately our community endocrinologist is swamped and just can't realistically get involved in mgmt of these patients perioperatively.

Curious if any other centers are taking a more conservative approach than say what that ASA consensus guideline suggests (1 week) which doesn't seem particularly rational...

 

[DocVapor]

Edit: meant to put this in the specific Semaglutide thread.