Concerned about extended fast before anesthesia

extendedfast
surgery
(Whitney) #1

Hi everyone. I am 35 years old and I am undergoing my second colonoscopy in just 48 hours to check my ulcerative colitis condition. During my last colonoscopy, I had not been fasting and I was not in ketosis. But now, I’m fasting regularly, I follow a ketogenic diet, and I am basically always in ketosis. I planned a longer fast for this week since I have to do the colonoscopy prep (there is no sugar in it, just laxative pills and water) and can’t eat food the day before anyway, so it seemed like a nice chance for a longer fast.

It has only just occurred to me that being in such a deep fast with high ketones could be a problem with the anesthesia that I will have during my colonoscopy. I have left a message for my doctor to ask him, but I’m wondering if anybody else has experience with being in deep ketosis during anesthesia. I am already 39 hours into a fast and if I keep going, that would send me into the colonoscopy being 86 hours into a fast (instead of the 24-36 hours most people have fasted before a colonoscopy) and presumably in really heavy ketosis. I am NOT diabetic, if that matters, and I don’t have any other hormonal, heart, or blood pressure issues.

I’ll wait for my doctor to call back but appreciate any anecdotes any of you can share about a longer faster or ketosis before undergoing anesthesia.

Thank you all!

(Ohio ) #2

Maybe I’m way off here: Isn’t the fasting necessary for the colonoscopy, and not the anesthesia?

(Whitney) #3

Most people “fast” for 24-36 hours before a colonoscopy but are NOT in ketosis because they are allowed to drink clear juice (no pulp), drink regular Gatorade, etc. the day before. Even the colonoscopy prep to empty the stomach and intestines often involves drinking a sugary laxative drink. My prep does not have sugar in it, since I opted for the sugar-free laxative pills with water. So most people going into a colonoscopy won’t have any solid food in their stomach or colon, but they definitely won’t be in ketosis, or at least, not very deeply in ketosis, because many of them will have drunk a gallon of apple juice or grape juice the day before. Even Popsicles, jello, and soda are allowed the day before. However, I won’t be having any of that. I’ll just stick to bone broth and water. I will also have been fasting for about 90 hours when I arrive for my colonoscopy instead of just 24 to 36 hours. So my ketosis will be much, much deeper, with much higher blood ketone concentrations, than the average person drinking clear sugar beverages and having jello for dinner the night before a colonoscopy. So my concern is not about an empty stomach, my concern is whether the high ketone concentration in my blood would cause any complications with the anesthesia medication.

(You've tried everything else; why not try bacon?) #4

What are they going to use? For my last colonoscopy, they gave me Propofl, which is not really even an anaesthetic, apparently. For one colonoscopy, years ago, they simply gave me Valium. In any case, general anaesthesia, with its attendant risks, is overkill for a colonoscopy. Anything they give you is going to be lighter, and less serious.

I’m not sure that the level of serum ketones is relevant here, and certainly, with ketones in your body, you will be well-protected, not like someone relying on glucose to see them through. Do you have any reason to suspect that ketone bodies in the blood stream will react chemically with the anaesthetic, or something?

#5

Nope! You’re technically still conscious… at some level. All I know is one second I’m talking to a nurse and then I was done! Good Stuff!

(Doug) #6

:+1: Agreed - I think they do the minimum. Had a colonoscopy last July, don’t remember anything. Ten years prior, I woke up at one point with the monitor of the proceedings in sight, and I thought, “Cool, that’s the inside of my large intestine…” I’m guessing they shot a little more anesthetic into me then; perhaps I raised my head or something.

My feelings are that they’re really good at it now - I woke up last year and felt fine. First thing I was told was that "We’ll give you some time to recover." :smile: 5 minutes later I was dressed and balancing on one leg to show that I was good to go. They still made me sit in a ******* chair for 15 minutes… FFS… :stuck_out_tongue_winking_eye:

(You've tried everything else; why not try bacon?) #7

Yeah, apparently the patient is still conscious, but Propofol messes with the memory of the procedure.

Each chemical they administer has a purpose, and each situation has different needs. I learned from having a couple of rats undergo surgery that the body still experiences pain even under full anaesthesia, so the rats were dosed with a powerful opioid as well, while they were under. The only problem was that the drug made them want to chew out the stitches once they regained consciousness, so they had to be watched for a while after they woke up, just in case. Once al the surgical drugs had worn off, the rat got a different pain reliever that didn’t have that side effect. Fascinating!

But general anaesthesia is to be avoided when at all possible, because of the risks, even in young, hearty patients.

(Whitney) #8

Thanks everyone. My doctor called back and said it was fine to go into my colonoscopy at the end of an extended fast.

I also talked to three people that fasted 3-4 days going into their colonoscopies and, anecdotally, all went well.

#9

Wishing you the best thru your procedure!! Hope all is fine for ya!! Sending good vibes your way!!

(Joey) #10

Great to know. Thanks for sharing - and best wishes for a forgettable procedure. :+1: