Trouble with G6 and BG after surgery

T1D, G6, MDI
I just got home from my 2nd hip replacement surgery. The first was exactly 8 weeks ago. I experienced elevated BG and insulin resistance after the first surgery, so was expecting it the second time. Just to be proactive (so I thought), I put on a new sensor the day before surgery this time and prepared for more aggressive dosing.

The anesthesiologist used the G6 and finger sticks during the 1.5 hour surgery, and ended up giving me two 10 unit doses of Humalog. (I don’t know what BG levels he was dealing with) Remember this is after no food for 12 hours (first surgery of the day). :scream: For comparison, I usually take a total of about 15 units Novalog per day.

By lunch time (first meal) I was down to 98, had lunch, a little more aggressive dosing, by 4 pm I was 382 :scream:. Dexcom was not reflecting the high BG. In fact, it was a total failure the whole time I was there. :rage: Fortunately I had my Contour meter with me.

My next finger sticks were 384, 437, and 401 at dinner time. Took 17 u Novalog and by 8:30 pm I was 435😱. Another correction, etc etc. The hospital protocol only allows insuIin with meals and one bedtime correction.

I had the night nurse wake me at 2 am for a finger stick, and I was 215. The hospital doesn’t allow corrections overnight, so by the next morning I was 440.

My orthopedic surgeon’s nurse said, “We need to get you the hell out of here!” So I was home before lunch.

Anyway you get the picture. I’ve never had BG that high, at least that I’m aware of, and not since G6 has been part of the team. The G6 was no help at all, it stayed suspiciously around 130 or lower, including multiple 55 down arrows, the whole time since the actual surgery. No amount of calibrating would help. I’m wondering if the extreme BGs right off the bat really fried the G6’s little brain?

Since I’ve been home, I’ve been able to keep my BG below 200 with aggressive (for me) dosing (I:C = 1u/5g), more aggressive and frequent corrections (1u/20 mg/dL), (increased basal, from 10 upto 12 u Lantus, may need more) and attempting a lower carb diet (not used to this). Don’t know how long this insulin resistance will last.

I’m trying a restart on the little G6 rascal today. :crossed_fingers:

(One of the worst parts of this adventure is that I think I shattered any confidence the many nurses had in CGM.)


Holy cow – you must have felt terrible, in addition to the trauma of the surgery! I am so sorry. Could your drop have contained dextrose? That just sounds so awful. :frowning: Glad you are home and recovering.



I don’t think I was given any dextrose, my husband was with me and that’s his job, to check all the IVs. :grin:

The Hospitalist supposed that since I had the other surgery recently, and had insulin resistance from the trauma then, that my body was already primed for a big reaction to the second surgery trauma. Kind of like a vaccine and then a booster, the second shot amps up your immune system. I don’t know, but that’s the best theory I’ve heard.


@jan Sorry you had the terrible BG’s post surgery, but hope the surgery went well and the hip works as advertised! I, too, had surgery recently and found my insulin needs were significantly higher (no BGs as high as yours, but my surgery was less invasive (hernia via Davinci laparoscopy). I talked with the doc post surgery and asked if steroids had been used, he looked it up and confirmed steroids were part of the IV’s make-up and probably were the source of my higher and wonky BGs. Perhaps that’s what sent you over the edge! Here’s hoping things settle down for you as you recover and get back to standard practices! Wish you the best with new hip and that it works for you a good long while!


My husband, a retired ICU physician, was horrified by your story!

We both send warm wishes for a speedy recovery! :pray::bouquet:


@TomH @CatLady

Thank you for the healing wishes! That’s one of the things I love about this community that you rarely see in other forums, the care for each other!

@TomH You have a great idea about the steroids, I didn’t think to ask while there, and none of the many :thinking:providers who were scratching their heads about the extreme BGs mentioned it. But, certainly a possibility! I will ask at my 2-week post-op appt with the surgeon.

Thankfully, with more aggressive dosing, I seem to have gotten a handle on it now. :slightly_smiling_face: