insulin drip protocol for mixing/priming: how do you mix it?

[TraumaJunkieRN]

I'm a recent new grad to the ER (today was my 7th day) and got my first DKA patient. Here's a quick run down of the story:

Patient brought in by ambulance with DKA secondary to running out of insulin and not eating for 2 days (pt decided to spend the money on meth instead). An insulin drip was ordered.

In our department, we mix our own insulin with 100 units in a 100ml bag of NS. A disagreement arose between nurses in teaching me how to prime the bag.

The old protocol was to mix the insulin in 100ml of NS, and drain the entire bag. Then mix another bag, spike it, and run it. The rationale is insulin sticks to the plastic of the tubing and therefore, the patient does not receive the intended dose of insulin. Coating the tubing with insulin will allow the rest of the insulin to flow through better.

The current protocol is to address wasting insulin and NS. The procedure is to mix the insulin in NS and drain the first 20ml. How do you guys mix it and is there any evidence-based research to substantiate this? I tried searching Pubmed and Google but couldn't find anything. Maybe someone here will have a better idea.

[suanna]

This issue came up many years ago with our insulin drips. I wish I could remember the chem class details that went with it , but the end result, we use the tubing designed for NTG drips. According to pharmacy at my hospital, it has very little reactivity with Insulin, and delivers the mixed dose accurately without pre-coating by wasting 1/4 the bag or more. Before that policy we always primed the tubing by running 50 cc of 125units of HR/250cc NS before starting the drip. Since we switched to nitro tubing, and stopped pre-coating, I've not seen a change in the hyperglycemia management from the beginning of the bag vs the end of the bag.

[MassED, BSN, RN]

insulin drips are *usually* now prepared within the hospital pharmacy. BUT, I have only ever mixed 100 units/100 ml - 1:1. I have never heard of insulin "sticking" to the bag...????!!!!! What does your pharmacist/s say? I would not even get involved in that nonsense. I'd go straight to the medication experts.

[MassED, BSN, RN]

Hazing is stupid, immature, and perpetuates this profession's reputation for eating their young. I don't tweet, and after you wrote that, I'm glad.

You're new in the ER and you're on your 7th day. You are learning. ALL of us had to start new in an ER at some point. Some one gave each of us a chance, so lay off of the poster, people!!!!!!!

[Tait, MSN, RN]

Wow, I wonder who tweeted this thread as "Scary that RN in ER without sufficient knowledge of DKA is asking on the internet how to manage!" I guess this is the hazing I get as the new grad :)

Just to be clarify, the purpose of this thread is not address the management of DKA but the technical details of priming an insulin drip and any evidence-based practice or experience surrounding the issue. Sorry if that was unclear.

Another stark reminder that everything we put out there is public. Sorry someone phrased it so poorly.

Tait

[Ahhphoey]

Wow, I had never heard of this before and I've mixed many an insulin drip bag. Definitely some good information, though, and I plan on reading more into this and asking my co-workers if they've heard of these differences with primed tubing.

[talaxandra]

This is exactly the evidence-based practice I was looking for. Too bad I only have access to the abstracts. Do you happen to have access to the full article? Thanks!

I do, but unfortunately it's through my uni so a link wouldn't work for you. I have access to both hardcopies and e-journals through work, as well - perhaps you could check your work intranet and see if the same's true for you. At least, with a couple of citations, you know what you're looking for :)

For what it's worth, I found the first article through google scholar, using the search terms: insulin infusion priming tubing; the second paper cited the first, which is how I found it. Glad this has helped.

[traumalover, RN]

Our policy is to prime with 50mls, same rationale, that the insulin will stick to the tubing. we mix 250 units in 250ccs.

[BittyBabyGrower, MSN, RN]

We just had an inservice on this...we are to prime our tubing and let it sit for 30 minutes...the insulin does have to coat the tubing/sink in or else as you run your drip the tubing will absorb the insulin thus decreasing the true amount your patient is getting.

[talaxandra]

Don't get me wrong, the patient had been stabilized in the ER with an insulin bolus, bicarb, fluids, etc.

I just noticed this bit of your post and was wondering what the pH and bicarb were, just because we so rarely give bicarb for DKA. My highest ever BGL, BTW, was 120.8mmol, or 2,176.6 mg/dL!

[MassED, BSN, RN]

We just had an inservice on this...we are to prime our tubing and let it sit for 30 minutes...the insulin does have to coat the tubing/sink in or else as you run your drip the tubing will absorb the insulin thus decreasing the true amount your patient is getting.

hmmmmm. Very interesting.

[mappers]

One thing I haven't seen addressed with all this talk of wasting insulin. We now have a "black bin" policy at our hospital. Certain medications have to be disposed of in special black bins so that pharmacy can dispose of it without it going to a landfill or into the water table. Insulin is one of those drugs. If you're just priming insulin down the drain, that's not good either.

(I'm a med surg nurse and don't really know anything about insulin gtts but found this thread insteresting.)

[TraumaJunkieRN]

I just noticed this bit of your post and was wondering what the pH and bicarb were, just because we so rarely give bicarb for DKA. My highest ever BGL, BTW, was 120.8mmol, or 2,176.6 mg/dL!

If i remember correctly, pH was 7.101, bicarb was around 6.3, BGL was 544 mg/dl. Dr. ordered 100mEq of sodium bicarb.