Pre-op Glucose

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Noyac

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So you see your next pt in the pre-op area. She is 40 yo with DM type 1, CRI, and anemia. Her labs are 3 days old and WNL except H/H of 10/30. Her Accuchek reads glu-300. She's scheduled for a AV fistula to be used at another date since she is not on dialysis as of yet. What's your plan? Do the case? Cancel the case? Treat the glucose and wait?

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So you see your next pt in the pre-op area. She is 40 yo with DM type 1, CRI, and anemia. Her labs are 3 days old and WNL except H/H of 10/30. Her Accuchek reads glu-300. She's scheduled for a AV fistula to be used at another date since she is not on dialysis as of yet. What's your plan? Do the case? Cancel the case? Treat the glucose and wait?

I'd likely just give her some insulin and go to the OR. Someone probably told her not to take any of her usual insulin because she was going to be NPO.

It's an AV fistula ... local and some light sedation are all she's going to get anyway.
 
I'd likely just give her some insulin and go to the OR. Someone probably told her not to take any of her usual insulin because she was going to be NPO.

It's an AV fistula ... local and some light sedation are all she's going to get anyway.

Would your management differ if she was having general anesthesia for something? I never like to fall back on the "oh there just having MAC or a spinal or whatever". All plans eventually have a GA as the backup.

Along those lines, would it differ if she was having some other procedure done? BKA? Lap chole? Ventral hernia with mesh?


Personally, I'd question her hx and what drugs she took or did not take and what her glucose usually runs at home. Then I'd give her some insulin and see how she responds and possibly start her on an infusion intraoperatively if necessary.
 
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Would your management differ if she was having general anesthesia for something? I never like to fall back on the "oh there just having MAC or a spinal or whatever". All plans eventually have a GA as the backup.

Along those lines, would it differ if she was having some other procedure done? BKA? Lap chole? Ventral hernia with mesh?

Your point is well taken, but the type of surgery and the likelihood that the case can be done with minimal or no anesthesia do influence my go/no-go decisions. This is analogous to the classic dilemma brought up when people say they're going to go regional to "avoid the airway" or "avoid a general" - on the boards you know what's going to happen, but in real life we sometimes do blocks for precisely that reason.

A derangement I might accept for an AV fistula I might not accept for an elective AAA, even though they're both technically vascular surgeries.

Personally, I'd question her hx and what drugs she took or did not take and what her glucose usually runs at home. Then I'd give her some insulin and see how she responds and possibly start her on an infusion intraoperatively if necessary.

Well certainly I'd probe deeper and get more history. If she didn't take her insulin because the preop nurse told her not to (which is how this scenario plays out most of the time) the glucose of 300 is expected and no big deal. I'd just give her some insulin and proceed, check once in the PACU, and send her home if she's not too far out of whack.

If her DM is always poorly controlled and 300 is "normal" for her, I'd probably still do the case. You could make the argument for postponing an elective procedure to better control her day-to-day glucose levels (wound infection risk etc), but honestly if she was ever going to get a grip and get on top of her disease, she'd have done it long before she hit the ESRD milestone. So I probably wouldn't delay an AV fistula - which she's going to need for dialysis soon - just because a person who's a poorly controlled diabetic all the time is also poorly controlled today.

If something else is going on - e.g., some unmentioned physiologic stressor such as an infection - and her glucose is climbing through 300 maybe on its way to DKA ... that's another story.
 
This is a fairly common situation and I would not hesitate to proceed with the case regardless of the anesthetic technique.
I would do my best to correct the hyperglycemia intra-op and post-op but other than that I would not do anything different than usual.
 
The question may be asked, "should we do it?"

We all have done cases like this. Although a fistula creation is minimally stressful, studies are showing chronic hyperglycemia (elevated HgbA1C) leads to worsened outcomes. We had a discussion on this before.


IF we can control sugars well for 12 weeks, get their A1c down, maybe then we should the major elective cases (5.6 cm AAA unruptured)???

Others argued we may never get the sugar down d/t pt compliance and disease.

Others argued, "just do it"


It makes sense that outcomes could be better for major elective surgeries with better preop CHRONIC glycemic control- it would be nice to delay those.
 
I'd likely just give her some insulin and go to the OR. Someone probably told her not to take any of her usual insulin because she was going to be NPO.

It's an AV fistula ... local and some light sedation are all she's going to get anyway.
Light sedation for an AV fistula?
I'll go straight with high sedation.
 
Do a block and call it a day

Sort of...

Any worries about the increased risk of nerve injury from a nerve block in a poorly controlled diabetic? If they are chronically poorly controlled, they already have microvascular disease and impaired blood supply to their peripheral nerves making them more susceptible to an insult from your block.


I have approximately zero objective studies backing this up, but more and more frequently I find myself omitting the epi from the local I use in patients like this if I'm doing a block to decrease the (sort of theoretical) risk of vascular compromise to the nerves.
 
I never use epi in blocks.

Do we know if the poorer outcome in patient with high BG is because of the single high value or because it's a reflection of a suboptimal management of the disease?
In any case i don't believe that in a 6 weeks time period patient will improve dramatically their compliance.
So yes in an ideal world diabetics would always have a BG between 80 and 120 ;) but it ain't happening.
 
When I was student rotating at BMC in Boston they had just implemeted some new pre-op glucose protocol (had a fancy acronym) which gave explicit instruction on how to deal with the above situation. It gave you parameters on how to dose Insulin based on finger sticks and when to adjust according to hourly rechecks perioperativly. And if you were in doubt you could call the the "glucose team," who I imagine would consult on how you should proceed. Curious how it is working, that was couple months ago.
 
Sort of...

Any worries about the increased risk of nerve injury from a nerve block in a poorly controlled diabetic?

No!

oh, and you should stop using epi in all your blocks. But of course this is just my opinion.
 
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This is a fairly common situation and I would not hesitate to proceed with the case regardless of the anesthetic technique.
I would do my best to correct the hyperglycemia intra-op and post-op but other than that I would not do anything different than usual.

Not picking on Plank here. Just that his response is what I expected from everyone and is exactly what I would do in this case.

How much insulin would you guys start with? How are you going to follow this glucose?

Pt tells you she takes 10u regular for anything over 300.
 
The biggest question to get answered is why the sugar is 300.

Decreased insulin administration probably number 1 but is not the only cause.

As long as pt is not in DKA or showing overt signs of sepsis, give some short acting insulin, 2/3 of what ever the patient would normally take. Make sure you recheck glucose in an hour or 2. start the case.
 
The biggest question to get answered is why the sugar is 300.

Decreased insulin administration probably number 1 but is not the only cause.

As long as pt is not in DKA or showing overt signs of sepsis, give some short acting insulin, 2/3 of what ever the patient would normally take. Make sure you recheck glucose in an hour or 2. start the case.

Very good (although I think we are on different tracks here). Why else would the glucose be 300?
 
Now I wish I would have piped up earlier, but I was thinking that the spot-on 300 value was a little suspect. How high does the meter read?
 
i would ask what her normal regimen was. Find out if she is brittle or not. If she just missed a dose, I'd give her 1/2 of that, assuming this would be a short procedure (the big "assumption"), or 10 of novalog if she was not brittle. Then go. Check glucose in PACU. If case goes more than 1 hour, fingerstick is easy, treatment is easy. Discuss intra-op (and pre-op) with surgical team.
 
Now I wish I would have piped up earlier, but I was thinking that the spot-on 300 value was a little suspect. How high does the meter read?

The meter goes much higher, i just picked 300 for the sake of discussion.

But my next question is, does the anemia make any difference?
 
pent, sux, tube...


POC glucometers have taken a lot of heat lately for being inaccurate. A central glucose would be more accurate.
 
This is a fairly common situation and I would not hesitate to proceed with the case regardless of the anesthetic technique.
I would do my best to correct the hyperglycemia intra-op and post-op but other than that I would not do anything different than usual.
Hello,

I agree 100%. Unless they are in DKA or some other life-threatening condition that would make anesthesia unduly dangerous, I would proceed, regardless of the anesthetic technique.

Greetings
 
No!

oh, and you should stop using epi in all your blocks. But of course this is just my opinion.

Why?

I like 1:400K epi. It's enough to bump the HR up if it's intravascular and it prolongs the block duration by 1-2 hours. In an otherwise healthy individual, I believe it does far more good than bad.

In poorly controlled diabetics, I tend to leave it out for concern of ischemia to the nerve.
 
Does any think the long term effects of hyperglycemia are worth controlling? Blade previously posted a lot of studies that correlated hemoglobin A1C to worse outcomes. We can effectively prevent the acute hyperglycemia/hyperosmolar effects with insulin and fluid. But what about the immunosuppresive and impact on wound healing that permanently glycosylated neutrophils produce? Those neutrophils don't magically rejuvenate with a bolus of insulin. Maybe we shouldn't be doing elective cases in a patient who has uncontrolled diabetes (which takes more than a point-of-care test to determine). But, I feel this is really more of an issue that falls on the surgeons and internists to fix before we see them.
 
Does any think the long term effects of hyperglycemia are worth controlling? Blade previously posted a lot of studies that correlated hemoglobin A1C to worse outcomes. We can effectively prevent the acute hyperglycemia/hyperosmolar effects with insulin and fluid. But what about the immunosuppresive and impact on wound healing that permanently glycosylated neutrophils produce? Those neutrophils don't magically rejuvenate with a bolus of insulin. Maybe we shouldn't be doing elective cases in a patient who has uncontrolled diabetes (which takes more than a point-of-care test to determine). But, I feel this is really more of an issue that falls on the surgeons and internists to fix before we see them.

Don't forget the endothelial dysfunction associated with the presence of advanced glycation end-products at all levels of the arterial tree.

FWIW, what do you do when someone is non-compliant? If they aren't controlling their DM today, what do you think will change in 3 months when you reschedule the case?
 
i would ask what her normal regimen was. Find out if she is brittle or not. If she just missed a dose, I'd give her 1/2 of that, assuming this would be a short procedure (the big "assumption"), or 10 of novalog if she was not brittle. Then go. Check glucose in PACU. If case goes more than 1 hour, fingerstick is easy, treatment is easy. Discuss intra-op (and pre-op) with surgical team.
I many diabetics cases, regime is irrevelant to A1C glucose.

I would consult an interdisciplinary team before the procedure (as all of you i supposed). As of me, I would try to control her glucose the sooner as possible and go for the operation whatever the glucose is.

I don't have the context in front of me, so it is difficult to give a straight opinion.
 
Another question, is the glucose measurement correct?


The standard bedside glucometers have issue with other drugs which contain maltose. The peritoneal dialysate "extraneal" contain maltose as well as an RA drug. The addition of these could falsely evlevate your glucose reading.
 
Hello again,

The guy needs his AV shunt placed either today or tomorrow, or within the next few days at most. You cannot postpone an AV shunt for ever. You guys are talking about this as if it were entirely elective.

Of course, it is not a matter of life-or-death within the next few minutes, but it isn't either a cataract or a lipoma that can wait for another year or two.

The multidisciplinary team can work him up postoperatively, if needed. We don't need them for a blood sugar of 300 on a diabetic that missed a dose of insulin.

Greetings
 
Hello again,

The guy needs his AV shunt placed either today or tomorrow, or within the next few days at most. You cannot postpone an AV shunt for ever. You guys are talking about this as if it were entirely elective.

Of course, it is not a matter of life-or-death within the next few minutes, but it isn't either a cataract or a lipoma that can wait for another year or two.

The multidisciplinary team can work him up postoperatively, if needed. We don't need them for a blood sugar of 300 on a diabetic that missed a dose of insulin.

Greetings

Except the scenario as described is a AV fistula in a patient is not currently getting dialyzed. That gives you plenty of time. I'd want to know whether the 300 is a 1 time fluke (in which case a bolus of insulin is all that's needed) or if the 300 represents the true chronic blood sugar. Noyac hasn't given enough information to know this.

What if it were an aorto-bifem for aorto-iliac occlusive disease? Would you delay based on the 300?
 
Just do the case already... jesus christ. Obviously not what you tell ABA examiners, but if anybody on here is saying they're going to cancel an A/V fistula for a sugar of 300 in a diabetic patient not in DKA, you know deep down inside that you're lying. If you actually would cancel it, make sure you do an awake F.O.I., just to be safe.
 
I would do the case, and I would not hesitate to tell the ABA oral examiners that I would do the case, assuming his chem 7 and abg are reasonable (I did something very similar on my oral boards and passed). I would explain my thought process and concerns and proceed. I firmly believe that there are no wrong answers on the board, it is a test of reasoning. They are not going to ask you questions that have definitive right and wrong answers.

I would definitely want to double check that level with a real lab test before treating. I don't trust isolated POCT checks anymore, although I think they are useful for trending once the initial reading is confirmed with a real blood glucose level.


- pod
 
OK there have been a lot of posts since I checked last so I will try my best to answer them all.
1) Consult Interdisciplinary Team. WTF? Are you serious? No way in hell, do the case.

2)This is an elective AV fistula all the way. She doesn't need dialysis for at least 4 months (a guess). But who in their right mind would cancel this case? Not the point of the thread.

3) Seinfeld, your onto something here. But she is not on peritoneal dialysis. So it isn't the maltose.

4) Let's say you give the pt 10 units of regular insulin (like I did). You go back to the room and start the case (like I did). At this point my partner relieved me so I will make up the rest of the case. You don't check the glucose for the rest of the case and then take her to the PACU. You ask the RN to check the glucose and she calls you saying that the glucose is 50. What happened?

Enough with the "what if ****". So the point of the thread is that the different finger stick glucose measuring devices (point of care devices, POC) have trouble measuring an accurate glucose in the face of anemia. All brands of POC glucometers overestimated the serum glucose, especially in the presence of anemia. The ranges of error rates for differing hematocrit (HCT) levels are:

7.5%-15.5% for HCT greater than 34%
15.2%-18.4% for HCT 25%-34%
15.4%-22.3% for HCT less than 25%


Mman, I have personally made a habit of omitting epi from my blocks for a few reasons.
1) extending the block for 1-2 hours just isn't that long when we are talking about a 16-24 hr block. It just isn't that reliably better in my mind.
2) Closed claims reports of nerve injury in pts from regional anesthesia were more likely to have epi in the solution last time I looked at it. I'm not interested in adding 2 hours to a 24 hour block and taking on more risk.
3) So when you inject intravascularly with local containing epi you get an increase in HR. You know what follows immediately after the increased HR?

Seizures.

So epi doesn't help unless you push the local very very slowly.

Why increase your risk if you are not getting anything out of it? Obviously, just my opinion.
 
i use epi in most my blocks because i can use more local with epi in it without reaching the threshold of toxicity. also, nerve injury is a known risk to nerve blocks. it is not medical malpractice if you get a nerve injury and as such i'd defend that case all the way to a jury, and probably win. to win a mal-practice case they would have to prove you deviated from the standard of care, which you did not.

but yeah, i'd do the case after a block (probably w/o epi in this case). I'd also give 2/3 dose of her insulin to treat that glucose after rechecking it.

i'd recheck the glucose each hour during the case, and immediately in the pacu. treat for anything over 250.
 
1:400 K epi is 2.5 mcg of epi per ml.

If you incrementally dose it (5 mls at a time, aspiration in between), you'll see an increase in HR before you've finished giving 15 or 20 mls.

And a single shot block lasting 16-24 hours? I find that to be the exception rather than the rule. My blocks work fine about 99.5% of the time with ultrasound, but it's rare to have a strong block after 12-16 hours.

Overall, though, I just think the 1:400k epi adds a margin of safety, both through detecting intravascular injection as well as decreasing systemic uptake of local.

(just my 2 cents)
 
1:400 K epi is 2.5 mcg of epi per ml.

If you incrementally dose it (5 mls at a time, aspiration in between), you'll see an increase in HR before you've finished giving 15 or 20 mls.

And a single shot block lasting 16-24 hours? I find that to be the exception rather than the rule. My blocks work fine about 99.5% of the time with ultrasound, but it's rare to have a strong block after 12-16 hours.

Overall, though, I just think the 1:400k epi adds a margin of safety, both through detecting intravascular injection as well as decreasing systemic uptake of local.

(just my 2 cents)


Fair enough. It definitely is an accepted form of practice

I've just noticed a trend in the other direction. Maybe it's more the people I've spoken with. But no epi in my practice and I haven't used it for over 6 yrs.
 
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