Coming Attractions

Here's something coming to a 'theater' near you.

Something we have been working on for a while, now with a renewed interest.  A new look at an issue in a different and detailed way.

That issue is the post op (perioperative) management of blood sugars in patients immediately after Bypass or Sleeve. 

My Question:  Is there a way to more precisely predict the precise degree of perioperative physiologic response of improved endogenous-glycemic control after bypass or sleeve?

The query is self-initiated when I write for insulin in the post operative orders.  Typically we see a marked improvement with 8-12 hours after surgery (even in the face of expected stress response to surgery), but where they settle out prior to discharge (usually a 1 day stay for Sleeves, a 2 day stay for Bypasses) can change subtly, but profoundly.

The interim product of enhanced glycemic control can mean the difference between going home on no PO meds, dramatically lessening the amount of basal insulin that was required preoperatively, or even getting off a pump and going with a reduced amount of basal insulin to satisfy the new insulin needs.

The clinical parameters of who will respond to surgery in the first place, and to what degree are in essence the same places we look for expected response metabolically just out of surgery.

Those measures are:

* Age of the patient? - The older the patient, generally >55, leads to possibly less pancreatic reserve, and with increasing age the more possibly pronounced the effect.

*Duration of Diabetes? - After 5 - 10 years of a timely diagnosis, again, possibly less reserve, increasingly likely the longer the duration of the disease.

*Degree of control? - As reflected by a glycohemoglobin of 7 or higher. Poorly controlled DM2 is increasingly toxic over time to the pancreas, but only reflects the prior 3 mos of averaged control, implying the higher the number the more unfavorable the control. The cause of this is as varied as poor adherence to lifestyle / diet / meds, to even possibly maxed out medical therapeutic options in the face of increasing weight and insulin resistance, becoming a true dead end street.

* Insulin-requiring? If they come to us already on insulin, this is an important indicator of preexistent pancreatic embarrassment, with more to come unless reversed.  Often, prescribing needed insulin leads to hunger, which leads to more weight, which leads to more insulin resistance, which leads to increasing insulin doses, leading to increasing hunger, then increased weight..... (That quip about the definition of insanity comes to mind-)

* C Peptide level?  Last in this list, but definitely not least.  As stated many times earlier in this blog, it appears more and more that this test, a surrogate for functioning pancreatic mass / effect, can fairly neatly wrap up the sometimes vague effects of all the other factors above, combined.  If what we are looking for in summation of this clinical markers is the end result of damage to the pancreas through a number of related insults, then the current secretory ability of the pancreas, as reflected in this blood test, "should" allow us to look at the C Peptide as an index to the here and now of pancreatic function.

Then, taking it one step further, the for the 'Coming Attraction', we may then be able to take that information, and apply some algorithm of the interaction of that reserve to the effects of surgery, and come up with a more precise model and prediction of the acute effect of surgery, in terms of expected insulin / medication needs.

The quotes around "should" are intentional. As in life, it seems like the more you know, the more you actually don't know.  (As long as you know that, you should be OK) We are probably just starting to scratch the surface of this and related issues, but I believe we are on to something here more than esoterica.

Logic doesn't always win the day, but it's a good place to start!

For the next post, I will detail a recent case of post op insulin needs in a patient who came to surgery on a pump with U500 insulin and 5 different basal settings.  I think you will be as impressed as he is with his new simple Rx protocol.