Blood glucose levels on preop liquid diet

I'm on day 4 of prop liquid diet, and was surprised to see my blood sugar levels get noticeably higher today.  The first 3 days' they were fairly low for me, but seemed to spike today.  My intake has been virtually identical each day.  I'm not particularly concerned because its not that high, just not what I was expecting.  Thinking it through now, it may simply be the liquid diet working as intended, and my liver may be releasing stored glucose in response to the low carb diet.  I'm curious if anyone else has any thoughts or a similar experience.

I was on clear liquids and drinking a low sugar cranberry juice.  It turned out to have a lot of sugar and I should have used the diet not the low sugar version.  Check the labels.

No hidden carbs.  Crystal Lite, water, sf jello and a bit of chicken broth.  Carbs coming almost exclusively from protein shakes - 7g from powder and 12 from milk.

While not high, I do remember my glucose levels being a bit higher than normal on the pre-op liquid diet.  It makes sense that it could be from your body processing stored fats.  As long as you aren't accidentally consuming extra sugars, I'd jus****ch it.  Good luck.