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Sam Ireland

2 Quick CALCS You Must Know


I will reluctantly admit that I am an AHA instructor... Whenever I teach ACLS or PALS classes and run students through scenarios, I hear people say a lot of the typical lines:

Student: "I would start a NE drip now"

Me: "What do you want to run it at?"

Student: "5mcg / min"

In the AHA classes I don't too often test to see if people actually know the logistics of how to perform that function in real life or not. However, when we get new clinicians at work, I love to test their med math abilities. Then, those interactions can continue a little bit:

Me: "How would you do that?"

Student: *Blank look on their face*

We should be able to quickly calculate and mix any infusion we may run into. In emergency medicine, we need to possess the ability to quickly and accurately start IV therapy for our patients. There are basically a few formulas you should know. How well should you know them? I'll let Mike answer that for me:

Some people did not like my "you had one job" comment, but I stand by it. When dosing a therapy for a patient, you should be focused on that task at that moment. Know the dose, and use a reference to confirm. Making medication dosing errors or not knowing how to initiate a therapy is completely unacceptable in our line of work - especially when there is often 2 or 3 EMS providers for every 1 patient.

What About The IV Pump?

'What about the IV pump?' The IV pump can be a great asset. However, it still requires you to know concentrations and how to mix and dose your medications. I have also seen clinicians have a wrong concentration programmed into their pump that they cannot change. When unforeseen problems arise with your pump, you will be dead in the water if you don't know formulas for dosing. You should be able to do the math, and simple enter in a VTBI (Volume To Be Infused) and a mL/H to get the correct dose in an emergency.

Make Your Simulations Count!

Make sure you are doing this in simulation at work. When we run through scenarios, I always have people actually mix the medications and start the IV infusion. Vials are provided, needles, syringes, IV pump tubing, IV pump, and a mock IV on the patient. Stay away from verbalization as much as possible in your simulations. It's the hands on skills and how much time and thinking they actually take that throws people for a loop when they actually run calls and have to perform these treatments on real patients. You're doing a disservice to your crews if you allow verbalization of these skills (if you have other options). Prepare them for the real thing!

Where To Start

So, where do you start if you are new to med math, or need to refresh on it? I made some videos a while back for new employees at Lifestar EMS, where I work. I have made two videos in the series so far, and will have two more to add soon. I cover mcg/kg/min, as well as mcg/min. I will be making a 'Part two' of this blog when I finish the "fluid over time" and "Unit/kg/hr" videos. Stay tuned, and check out these two videos!

MCG / KG / MIN

MCG / MIN

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