Ketones and Auto Mode 670G

Diabetes Technology Commercial Closed Loop Systems
1

Hello! Brand new to the forum, so thanks in advance for any feedback!

I have been struggling with the 670G, with Guardian3 sensors in Auto More. I had a disturbing issue that neither Medtronic not my trainer seem to have an answer for. I’m curious, has anyone else out there has experienced it?

The first week I started on Auto Mode, I noticed I felt off. I had a very strange persistent nausea, which I dismissed, assuming it was something else. My first few weeks in Auto Mode, I had some struggles, especially with correcting highs, but overall the time in range time looked good. I didn’t love the constraining feeling if the system, so I would occasionally go off a week, and then try again. The nausea returned each time. Finally, after a few weeks and the nausea coming off and on, I realized what it felt like. I remember thinking, “I feel like I’m running a high blood sugar”, but I was testing at 154 (sensor read 120s) Then I tested my ketones, and sure enough I was passing small ketones. I’ve been a Type 1 for over 20 years and never experienced ketones with a blood sugar that was not over 200. I got out of Auto Mode and corrected and drank a ton of water. The nausea went away and so did the ketones. I tried Auto Mode again, primarily as a test. And sure enough it happened again, more nausea and more ketones, this time with a 182 blood sugar (sensor at 140s).

I quit Auto Mode then and reached out to Medtronic with the issue. He said from what he could see the system seemed to be working well. He asked if I was on a very low carb diet, which could be a factor, but I’m not.

The only explanation I can come up with is that Auto Mode underestimated my basal insulin, so my body was unable to metabolize the sugar in my blood stream, even though it was not dangerously elevated.

I’m currently talking with a trainer, but primarily she wants me back in Auto Mode, which I am not comfortable with at this time. I have an appointment with my doctor, but he’s notoriously hard to see and it isn’t for a couple months.

I’d really appreciate hearing thoughts and if you or someone you know has experienced this!

2

Keytons can occur in a number of instances not just related to diabetes.

Here is an explanation from a release by the University of Rochester Medical Center.

“Exercising strenuously, taking certain medicines, and following a special diet, such as a low-carb or high-fat diet, may affect the test.”

https://www.urmc.rochester.edu/encyclopedia/content.aspx?contenttypeid=167&contentid=ketone_bodies_urine

In fact as a T1 I have had low level Ketones a number of times, usually when I am ill and not eating for some time.

Keytones usually show up in people with diabetes when blood sugar exceeds 300 for a prolonged time. Yes everyone is different and 300 is not an absolute. Discuss the matter with you endocrinologist. However, i doubt it has anything to do with the Medtronic pump.

Now I have to do a disclaimer:

I am a Medtronic ambassador. My opinions are my own. They did not pay me to say nice things. OK, they sent me a shirt and a cup but even I am more expensive than that.

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3

Didn’t we recently decide/discuss that people can get ketoacidosis with semi-normal blood sugars. People were talking about this happening. Weren’t they? It was a new idea to me.

“In some instances, it does occur in the presence of normal glucose levels. This latter form of DKA is known as euglycemic DKA, which is defined as ketoacidosis with blood glucose levels below 250 mg/dL.”

Metabolic ketoacidosis with normal blood glucose: A rare complication of sodium–glucose cotransporter 2 inhibitors - PMC.

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4

Thank you for taking the time to reply and send the information! Interesting reading about the different causes of ketones, some of which I was unaware of. I’m not sure the other possible causes applied, unless I had an infection of some kind and didn’t know it. Good food for thought though, and gives me some other questions I could ask when I see the doctor.

5

Thank you for sharing this, I found it very interesting! It prompted me to do a little more research and I found this quote in an article that may apply to my situation: “The primary cause was reduced availability of carbohydrate, possibly in conjunction with reduced insulin dose.

https://care.diabetesjournals.org/content/38/9/1638

I often have to work through lunch, so it may be 6 hours of fasting before dinner. I wonder if it was a combination of factors that caused my ketones; no carbohydrates and the pump withholding insulin to prevent me from going low. It’s worth looking into, and I will ask this question of my doctor too.

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6

Mohe0001

I had not read the article so that was good information. I believe Ketones occur whenever the body is converting fat to energy. Think of the liver getting brain signals for energy and no carbohydrates to convert. It goes or fat using acid.

As i was losing weight my ketones were always positive. I needed ketones to covert that fat. I under consumed carbs in order to reduce fat. Usually only in traces. But the doctor was never concerned about it. Also i never lapsed into keto acidosis. Why? Well tha cid never overwhelmed my body. My blood sugar beverage went above 250 and never over 200 for a sustained Period.

Honestly it was ok.

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7

I appreciate you sharing your experience! May I ask did you have symptoms from the ketones during that time? Such as nausea or muscle aches?

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Welcome to TuDiabetes, @Nicole6! Your case is interesting. How are you testing your ketones when you experience nausea? I suspect you may be using urine test strips. I’ve read that dehydration is one of the causes for inaccurate readings in urine strips.

You may want to consider getting a ketone meter and strips that use blood. It is more accurate and can be a big help when you do go very high with your blood sugar level, like > 250 mg/dL.

In my last episode of nausea that caused me to check my blood ketones, I measured 4.7 mmol/L. (This is high, but not DKA high, a transition level that provides a good warning.) I believe my BG was north of 250 at the time.

That independent confirmation motivated me to take serious counteractive measures (lots of water, inhaling some Afrezza, and an intramuscular shot of rapid acting insulin) to prevent progression to diabetic ketoacidosis. I also changed out my infusion site which I believe was the actual cause of the event.

What you’re describing, with a BG of < 200, hints at euglycemic DKA, especially with the nausea symptoms. This issue has been talked about more recently with the emergence of new drugs used to primarily treat T2D. I really think you would benefit from getting a blood ketone meter as that would allow you to report specific credible ketone levels to your doctor when this happens.

Good luck! Please report back to us if you learn anything more.

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9

Thank you so much, Terry! This is very helpful. I appreciate you sharing your experience! Yes, I have been using the Ketostix for urinalysis. I really like your idea of getting a blood monitor for more accurate readings. I’m not currently on any type 2 medications, but did find learning about Euglycemic DKA enlightening. I too wonder if that’s what I experienced.
I plan to take your advice, get a ketone blood monitor and then keep a good record of when it happens, and what happens before and after. I have not experienced it while on my normal pump basal rates, so I will switch back in Auto Mode and see if the condition presents itself again. Then I’ll have a good record to share with my doctor and trainer, and hopefully find a solution!
I’ll be sure and update here, thanks again!

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10

Nicole,

I did not have pain, or nausea issues

11

Good to know about the meter! I just got my urine strips refilled (my previous rx was 10 years old). But maybe I’ll purchase a Keaton meter. Generally when I use them I’m ill and thus at some level dehydrated. Good to know!

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Can you download pump info and see what your total basal/bolus was during that time, compared to before you started automode?