student with blood sugar question.

caroladybelle, BSN, RN · Jun 30, 2006

First, why the potassium was in the IV. Insulin frequently causes potassium to shift into cells and out of the blood, dropping serum potassium. If you know that you will be giving more insulin than usual, many orders will automatically have some potassium supplementation. And some MDs routinely include low amounts of potassium in the IV, figuring on some diuresis and hemodilution.

As far as D5W being infused, first remember that there are not that many calories in D5W, to begin with. And even if/especially if they are admitted with DKA, the MD does not want to drop the sugar too rapidly as there can be serious complications from that. While they will cover with insulin, they may continue some dextrose, to give the insulin something to work on and to prevent a seriously precipitous drop.

papawjohn · Jun 30, 2006

Hey Bucky!!!

I'm going to assume (frequently not a smart thing to do) that your Pt had been admitted with DKA, OK? And if that is incorrect, my answer may not be a very good one.

The Pt with DKA has several really screwed-up fluid & electrolyte problems all at once. First, they are severely dehydrated because the high BloodSugar they've been running (think about it--they've had a steadily increasing glucose for probably days!!) means they've been diuresing for that time. So the first thing we do is give lots of Saline IV. Typical order would be 1000ml bolus, 250ml/hr X 8hr.

Their cells, naturally, have not been able to use the sugar in their blood--so the cells are stressed and dying. This spills potassium into the bloodstream. They will arrive with elevated K+ (Potassium being intRAcellular, right?). But this doesn't last very long. First, we dilute the concentration of the blood by giving all that Saline. Second, we give Insulin which gets the cells back into the metabolism business and they start sucking that K+ out of the circulation and back into the cells where it belongs. Unfortunately, lots of it was pee'd out so not enough is left to 'fill' the cells. So the K+ will start high but quickly drop to possibly critical levels. Frequent labs are done to follow this. You'll give boluses to keep it WNL. If you haven't figured it out yet, let me tell you a little trick: Giving K+ in high concentrations thru a peripheral line really can hurt!!! It will also cause raging local phlebitis. So with every Lab draw, start a new heplock until you have 2 'spares'. You're going to need them.

Third, obviously we start an Insulin gtt and titrate based on frequent AccuChecks (or whatever you might call 'em where you're at). This starts a downward trend in the blood sugars. But we don't want to have that downward trend gather speed and keep going; the BS would be 30 before you know it!! So typical orders would be:

1. Accucheck q1h with titrating Insulin gtt.

2. When Blood Glucose

1/2NS with 20KCl at 100/hr.

3. When BG

Common experience is to get the BS down from 600 to 800 within a couple of hrs, then to 'play' with it in the 200 range for the rest of the day. This is not a bad thing for that Pt--it gives the 'lytes and fluids a chance to even themselves out.

After a day (or maybe less) you'll DC the Insulin gtt and move to SubQ sliding scale. There is usually a period of up and down BSugars with this transition. Follow it closely but don't panic and restart the drip. Call the MD if the SubQ doesn't seem to be working and see if you can increase the SubQ dose.

And don't even think about how we had to do this before there was bedside Glucose monitors!!!!

Hope that helps

Papaw John

PS: Hey Caroladybelle!!! Good point about the Dextrose in D5!! I think that a liter bag has about 75-100 calories. Less than in a Bud Lite!!

P-J-

palesarah · Jun 30, 2006

Hey Bucky!!!
I'm going to assume (frequently not a smart thing to do) that your Pt had been admitted with DKA, OK? And if that is incorrect, my answer may not be a very good one.
The Pt with DKA has several really screwed-up fluid & electrolyte problems all at once. First, they are severely dehydrated because the high BloodSugar they've been running (think about it--they've had a steadily increasing glucose for probably days!!) means they've been diuresing for that time. So the first thing we do is give lots of Saline IV. Typical order would be 1000ml bolus, 250ml/hr X 8hr.
Their cells, naturally, have not been able to use the sugar in their blood--so the cells are stressed and dying. This spills potassium into the bloodstream. They will arrive with elevated K+ (Potassium being intRAcellular, right?). But this doesn't last very long. First, we dilute the concentration of the blood by giving all that Saline. Second, we give Insulin which gets the cells back into the metabolism business and they start sucking that K+ out of the circulation and back into the cells where it belongs. Unfortunately, lots of it was pee'd out so not enough is left to 'fill' the cells. So the K+ will start high but quickly drop to possibly critical levels. Frequent labs are done to follow this. You'll give boluses to keep it WNL. If you haven't figured it out yet, let me tell you a little trick: Giving K+ in high concentrations thru a peripheral line really can hurt!!! It will also cause raging local phlebitis. So with every Lab draw, start a new heplock until you have 2 'spares'. You're going to need them.
Third, obviously we start an Insulin gtt and titrate based on frequent AccuChecks (or whatever you might call 'em where you're at). This starts a downward trend in the blood sugars. But we don't want to have that downward trend gather speed and keep going; the BS would be 30 before you know it!! So typical orders would be:
1. Accucheck q1h with titrating Insulin gtt.
2. When Blood Glucose
1/2NS with 20KCl at 100/hr.
3. When BG
Common experience is to get the BS down from 600 to 800 within a couple of hrs, then to 'play' with it in the 200 range for the rest of the day. This is not a bad thing for that Pt--it gives the 'lytes and fluids a chance to even themselves out.
After a day (or maybe less) you'll DC the Insulin gtt and move to SubQ sliding scale. There is usually a period of up and down BSugars with this transition. Follow it closely but don't panic and restart the drip. Call the MD if the SubQ doesn't seem to be working and see if you can increase the SubQ dose.
And don't even think about how we had to do this before there was bedside Glucose monitors!!!!
Hope that helps
Papaw John
PS: Hey Caroladybelle!!! Good point about the Dextrose in D5!! I think that a liter bag has about 75-100 calories. Less than in a Bud Lite!!
P-J-

papawjohn- you're an awesome teacher, and I just had to say so. This isn't the first post I've read where you have thoroughly explained something I didn't fully understand, in a way that is both easy to comprehend and easy to remember. You've got a way with words that paints a picture of the process in my head. Thanks for sharing your knowledge!

caroladybelle, BSN, RN · Jun 30, 2006

Papaw,

I am not sure about the calorie content, but I always thought that it was 150-180 per liter. But either way, that still is not all that much spread over 8 hours ( at 125cc/hr), especially in a patient that feels cruddy and is not eating much.

I always love it when people freak out over a 50cc IVPB mixed with D5W, about how that it is what is wrecking the patients' dexichecks (am in the Northern climate assignments right now - and they use "dexis" instead accus). They don't even blink at the fact that patient has a raging febrile infection, and that is most likely what is clobbering the dexis.

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PS. How is the weather down there? Any more sinkholes swallow up lakes? Their raining to drown all the politicians outta DC, up here.

papawjohn · Jun 30, 2006

Hey Back to ya C-L-B-!!!

Our self-emptying lakes and house swallowing sinkholes are just the barest surface of the surreal here in Fla. I've been here about 6yrs now--still find the place amazing.

Still miss the mountains at times. Mine are in Tennessee.

Regards to you'uns

Papaw John