September 26, 2010

Surgical Site Infections Rise Dramatically when Blood Sugar is over 140 mg/dl

Though doctors call them "diabetic" complications, many studies conducted in cell cultures, animals, and humans, which you can read HERE, point to the conclusion that organ damage due to high blood sugars starts at levels that doctors label "prediabetic."

Now another study--one that looked at the factors causing post-operative infections has come up with the same finding.

The study is:

Postoperative Hyperglycemia and Surgical Site Infection in General Surgery Patients Ashar Ata et al. Arch Surg. 2010;145(9):858-864. doi:10.1001/archsurg.2010.179

You can read a good summary of this study, with more information than is found in the abstract here: Science Daily: Postoperative High Blood Sugar Appears to Be Associated With Surgical Site Infection

The researchers examined the records of 2090 patients. For 1561 of these patients, blood sugar measurments were recorded and 803 of these blood sugar measurements were taken within 12 hours of surgery.

The researchers found that in the group as a whole the following factors were predictive of surgical site infection (SSI):
increasing age, emergency status, American Society of Anesthesiologists physical status classes P3 to P5, operative time, more than 2 U of red blood cells transfused, preoperative glucose level higher than 180 mg/dL... diabetes mellitus, and postoperative hyperglycemia.
But here's where things get interesting. Because the researches found that,
After adjustment for postoperative glucose level, all these variables ceased to be significant predictors of SSI; only incremental postoperative glucose level remained significant.
And what was the postoperative glucose level at which bad things started to happen?

Readers of this blog, don't all answer at once, but you're right!

It was 140 mg/dl the very same blood sugar level we have long been telling people with diabetes should be the very highest they ever let their blood sugar reach if they can possibly avoid it.

In the type of surgery studied in which post operative infection was by far the most common--colorectal surgery, where 14.11% of patients suffered infections, the researchers found that those with blood sugars higher than 140 mg/dl were over three times more likely to suffer infection as those without.

Science Daily also quotes the full text article as saying,
In conclusion, we found postoperative hyperglycemia to be the most important risk factor for surgical site infection in general and colorectal cancer surgery patients, and serum glucose levels higher than 110 milligrams per deciliter were associated with increasingly higher rates of post-surgical infection.

What makes this study so important is this: If you go in for a major procedure it is almost 100% certain that, despite your protests, the anesthetist will hook you up to a glucose drip before surgery. This guarantees that no matter how perfectly you have been eating, your blood sugar will be at least 140 during your surgery--a number that surgeons, trained to believe that 200 mg/dl (11.1 mmol/L) is "Diabetic" will tell you was a "nice normal blood sugar" as mine did.

The only way to avoid this is to negotiate it with the surgeon before you commit to the surgery and get it in writing in a form that you can give to the hospital staff before the surgery.

No matter what you have been told orally, the staff in the hospital will listen only to the surgeon and pay attention to you only if they see written instructions that look like they could lead to a law suit.

Unfortunately, if my experience is anything to go by, getting such written instructions may be impossible, even with an otherwise excellent surgeon. Therefore, it would be a good idea to print out this study and keep it in your file of important medical papers so that you can take it with you when you have your preliminary meeting with the surgeon.

Once your surgery is done, you are not out of the woods. The food you will be given in the hospital will be the "diabetic menu." This may be called a "Carb-controlled diet" (It was at the hospital I stayed in) but this is misleading. It is, in fact, the same old dangerously high carb/ low fat diet that nutritionists still defend to the death--the death of the patients with diabetes who eat it.

For breakfast you'll be offered toast with jelly but no butter, cereal with skim milk, and sugary fruit, so that you face the choice of starving or raising your blood sugar well over that 140 mg/dl level. The rest of your meals will be thin slices of fat free mystery meat and starchy veg, with fruit--canned in corn syrup--for dessert.

Again your only defense here is signed orders from your doctor, which may be very hard to attain. That is because most doctors do NOT understand that the carbs you eat are what raise your blood sugar. They really don't.

And they remain convinced that blood sugars up to 200 mg/dl are not dangerous and that it is a mysterious disease called "diabetes" that harms people, not exposure to high blood sugars.

Doctors also believe, without question, that high fat diets cause heart attacks and that it is much healthier for you to eat that toast and jelly than a fresh egg.

So before you go into a hospital for elective surgery, if possible, get a letter, signed by your surgeon or another doctor who practices at the hospital where you are having your surgery ordering the nutrition staff to allow you to order at will from the regular menu and forbidding them to make you eat foods from the "diabetic" menu.

If it isn't possible, arrange for friends or family members to bring you the foods you need to eat to keep your blood sugars normal. Arrange to go home where you have control over your food supply as soon as it is possible.

If you are forced to go to a nursing home after surgery, make sure that your doctor orders the nursing home staff to allow you or a chosen family member who understands your dietary needs to control what you eat and, again, forbid the use of the "diabetic" diet. Otherwise, you will be forced to eat the high carb/low fat diet that will raise your blood sugar and make surgical infection more likely.



Lori Miller said...

Maybe the hospitals around here where my mom has stayed are different. She didn't have surgery, but she has diabetes and ordered whatever she wanted off the regular menu. There's good low-carb fare, and that's what she orders.

country mouse said...

after I had my coronary stent, there was nothing on the menu that could be considered low-carb so I just fasted until I got home.

I'd also caution people on beta blockers. They really can pack on the pounds. I gained back something like 15 pounds in three weeks and I hadn't changed my diet significantly. Now I get to lose the weight all over again and have my cardiologist nag me about cardioprotective factors of beta blockers. I nag him about memory deficits, weight gain, and fatigue.


Jenny said...

Country mouse,

A known issue with beta blockers is that they turn off counterregulation, which means if you are on insulin or an insulin stimulating drug you can experience severe hypos.

DAR said...

Having surgery and/or being admitted into the hospital is one of my biggest fears! In fact, it was after having major sinus surgery that my health deteriorated and my weight increased dramatically despite my efforts to "eat healthy" as the ADA advised.

It took me over a year to figure out I have diabetes because my doc only tested my fasting BGL despite my history of gestational diabetes.

If I ever end up in surgery or the hospital again, I will starve before I eat their carbage and do my best to make sure they don't pump me full of glucose!

Thank you for this article and all you do to keep us informed, Jenny. You are truly one of my heroes and I've created a webpage to announce my Top 20 Low Carb Heroes publicly:


Jan Blawat said...

After I had surgery, I was brought a diabetic breakfast of whole wheat pancakes and sugarless syrup. I couldn't believe my eyes. "I can't eat this!" I said. The nurse offered to bring me pudding or a fruit cup.

I have an ongoing problem with my toes caused, I believe, by something going on inside the foot. The podiatrist insists it's because I'm diabetic, even though my A1C has been 5 for 2 years. Once they label you as diabetic, most doctors won't look past that as a cause for everything. It's so frustrating.

I read your blog to keep myself up to date for what has become monthly "discussions" with the podiatrist.

Michele said...

I had a sternotomy almost two years ago. Saw the endo before my surgery and he wrote a prescription to have my blood sugar tested three times a day while I was in the hospital. The first testing, post surgery, was in the high 200's. It had never been that high - never over 190 ... so I was alarmed. I was on insulin for 4 days which prompted visits from drs. I had never seen before and didn't know ME. The nurse gave me a shot one night and then told me I had better eat the peanut butter crackers or I'd be hypo...craziness. The glucose drip coupled with my fasting pre-surery started me on the merry-go-round - that makes perfect sense. But when you're in the hospital and sensitive to pain is tough to sort things out.

Helen said...

While I don't spend a lot of each day over 140, my bg does go above this every single day. It comes back down, though, usually within an hour. There doesn't seem to be much I can do about this right now. I've tinkered with my diet all I can. I do spend a good part of each day above 110.

Having blood drawn for MODY 2 tomorrow!

I don't seem to be prone to infections, surgical or otherwise, but I'll be aware of the IV situation if I ever have to have surgery again (been through several, before dx). I can't eat the hospital food anyway, for many reasons.

Helen said...

I meant to ask when I started the last comment, but got sidetracked, was, I wonder (hope) whether a brief post-prandial 140+ is not what they're talking about, but a more constant level?

Jenny said...

In that study, they were reviewing old medical records where there were often only a few blood sugar measurements taken per patient, so there is no way to know if they caught a spike or a very high sugar coming down, or a steady sugar.

Pubsgal said...

Thanks for another awesome article, Jenny! I'll be sure to get materials together and have them ready in the event of hospitalization or surgery.

I remember being in the hospital when my daughter was born (my 2nd round of gestational diabetes) and feeling so surprised at how carb-laden the diabetic menu was. I ate 1 carb serving and all the protein at the meals and left the rest.

On the other hand, there are some hospitals that are savvy. My mom had heart valve replacement surgery at Santa Barbara Cottage Hospital. Even though she does not have diabetes (nor did they have any reason to suspect that she did - it doesn't run in her side of our family), her blood glucose was strictly monitored and kept below 125. She was very surprised by this, but the doctors do this for all of their heart patients, to promote better healing. (I wasn't quite as surprised as she was, but I was delighted that they were so proactive about this for even non-diabetic patients.) I was kind of surprised that the diabetic menu did include more carbs than I would eat - I think they went by ADA guidelines for the nutrition part, oddly enough. Which I guess would work okay for your non-diabetic patients, but it would put more of a bolusing burden on the nursing staff, you'd think.

Jenny said...


Since the ADA warns that it may be dangerous to let blood sugar drop below 180 mg/dl (check out the page named "Tight control" on their web site)I doubt nurses do much bolusing for any but Type 1s. They don't seem to pay much heed to blood sugars until they get into the high 300s.

Pubsgal said...

Nope, she was given at least 1 insulin injection when I was there, to keep her blood glucose levels at 125 or below, by order of the surgeon. Which is why I was a little surprised by the amount of carb allowed on the diabetic menu; on the other hand, that was probably their standard diabetic menu, and not one targeted to the heart surgery patients.

TJ the Grouch said...

Great blog, as always. I have a dumb question, though. Whenever you say "blood sugar" do you mean blood or plasma sugar? That also applies to your book (not the very last one).

Jenny said...

All meters in the US now are standardized to give what used to be called "Plasma" blood sugar values which means that their readings should match a readings drawn at a lab if taken at the same time. I'm referring to those values when I give numbers.

A few brands of meters (but not all) sold in the UK are still using the old "blood calibrated" values and will give readings 12% lower.