ICU IV insulin management - what to expect

Hi everyone,

I’m posting here because I’m trying to understand something that happened to a very close friend of mine during an ICU admission at Stanford Hospital in June 2025. I am a Type 1 diabetic myself and have an upcoming surgery so I need am trying to understand hospital IV insulin management from a safety perspective in case I end up in the ICU.

My friend has pancreatic insufficiency but is not diagnosed as Type 1 or Type 2 and is not on steroid therapy. He normally uses approximately 20–30 units of insulin per day total. Historically, his insulin requirements would be are around 1–2 units per hour at most using a pump or IV. During this admission June last year, he was NPO (no food) for two days.

While in the ICU, he was placed on IV insulin and using an online “calculator” built into the hospital’s electronic medical record system the nurses adjusted his IV insulin rate. For approximately two periods of seven hours, he received between 5 and 9 units per hour of IV insulin without communication or consent with the patient or family. During that time, his glucose levels dropped rapidly. I had his Dexcom data remotely and could see the fast downward trend in real time and an IV dextrose rescue bolus was eventually administered.

To illustrate the above, the attached graph has the amount of insulin administered and the glucose levels over a period of three days. The blue bars represent IV insulin rate in units per hour, the yellow markers dots are hospital blood glucose measurements, and the green line shows the Dexcom continuous glucose monitor data.

I am trying to understand whether this type of dosing is typical in an ICU setting. Is it common for IV insulin calculator to generate 7–9 units per hour for someone with pancreatic insufficiency who is not on steroids, not in DKA, normally uses 20–30 units per day total, and has been NPO for 2 days? Do most hospitals rely on fixed sliding scales, dynamic calculators, or some hybrid? Is there usually a requirement for a second nurse or physician sign-off above a certain hourly threshold and are the doses given communicated with the patient? I was told by the doctor that this calculators does not take into account the diabetes type and the baseline insulin sensitivity of the patient.

It took 16 separate requests before I received the insulin dosing and glucose data from the hospital, I did have access to the Dexcom data immediately.

I requested an in-person meeting with endocrinology leadership to understand how the IV insulin calculator determines dosing and what safeguards exist, but those requests were declined and no explanation of the calculator thus far has been provided.

My question is: how do ICU IV insulin protocols typically work and what questions I should be asking anesthesiology (tomorrow) during my own surgery before consenting to hospital-managed insulin? Is the use of the calculator standard practice everywhere? What are the safeguards when a calculator is used?

If anyone here works in hospital endocrinology, ICU nursing, anesthesia, or has experience with IV insulin protocols, I would really appreciate your perspective. As someone living with Type 1 diabetes, the experience of my friend, has made me anxious about future hospital care, and I want to approach it informed rather than afraid.

Thank you very much for any insight you can share.

My experience with surgery is limited to outpatient and I’ve never been in ICU but since you are having a procedure tomorrow I will share what I can. I had one procedure where I attempted to inform the team of my CGM and instruct on what to do in if/then scenarios - only to be told those instructions would have to come from my doctor. I could postpone very last minute if wished to do that but I decided to take my chances.
That said there are people on the forum who have arranged - presumably in advance - to handle their own diabetes care while letting the medical team manage everything else. I don’t know if hospitals have their own policies. Hopefully you will get responses from people who have had success.
@Dennis
@joe

Hello @vavi1 Welcome to Breakthrough T1D. I’ve had 2 surgeries, one an emergency appendectomy and for both I worked out insulin management with the doctor before hand. Also, and as a result of these pre surgery meetings, I left my pump on, and was allowed to check blood sugar using my own equipment, and administer insulin as I self directed. Since it was “in my chart” i was able to successfully take care of my short stays (the appendix was complicated so I stayed overnight in recovery) I can ask what hospitals do regarding iv insulin (I have a contact at NYU) but I can only assume it is not aggressive and that lows are over treated. It’ll take a week to get anything back if you think that would be helpful.