management of pre/eclampsia with magnesium sulphate.

[bluefabian]

I need help in the management of pre/eclampsia with magnesium sulphate.

Our stock came in 2.47g/5ml at concentration of 49.3%.

The leaflet stated that a dilution of 50% needs to be further diluted into 20% before administration via IV can commence.

If the ordered dosage is 4g, how does one prepare the dilution?

Thanks in advance.

[Mukfay]

I think I know, but I'm a student, and I wouldn't want to make a mistake with a drug like this one. Can you contact the pharmacist or the manufacturer?

Regards,

Mukfay

[bluefabian]

The leaflet said that a minimum diluent of 7.5ml needs to be added up to the 5 ml stock, to make up of a total of 12.5ml solution.

A breakdown though -

50% = 1 : 2

20% = 1 : 5

So,

if 50% (or 1 : 2 parts) is 5mls,

1 : 1 = 2.5 ml

1 : 3 = 7.5 ml

1 : 4 = 10 ml

1 : 5 = 12.5

1 : 6 = 15 ml

or another way to put it, 5/2 X 5 mls = 12.5 ml

That's for a stock of 2.43g in 5ml.

_______________________________________________

I hope my explanation is correct. It is rare for me to come across a medication that needs the nurse to dilute it into a weaker strength such as these. So I need clarifications on how other nurses are doing it.

Anybody else care to explain their unit routine?

[I_LOVE_TRAUMA, RN]

Call the pharmacy...they are your best resource

[bluefabian]

I did actually and hoping to hear their response.

[Medic09, BSN, RN, EMT-P]

I did actually and hoping to hear their response.

Really? When I call our pharmacy, I get an answer. Usually on the spot, while I wait on the phone. Occasionally they call be back quickly.

Now, to your problem. Over what time were you planning on giving this? Typically it's run in over anywhere from 10 minutes (near frantic, but not a code) to 20 or 30 minutes (merely in a hurry). With that manner of administration, you can be running it in with a 1/4 liter bag of saline to carry and dilute it.

Our stock Mag Sulfate for such applications comes 4g in 500 ml (or maybe it is 250 ml).

Disclaimer: All the above is for the sake of discussion. I do not claim to know what I am talking about. Nor should you understand any of this to constitute practical advice.

[bluefabian]

Since this is an ER and not a labour suite, the administration is to be given in the time frame of 10 - 15 minutes. 30 minutes max - solely for the management of pre-eclampsia or eclampsia.

A 2 gram ampoule can be diluted with 7.5ml NS or dextrose saline to make up 12.5ml - which makes up a dilution of exactly 20%. I was taught to dilute it to make up to 50 ml total dilution which will arrive at a 5% concentration.

I used to work in a place where the pharmacy prepares the dilution, but here all things (except topical solutions) came in fresh in ampoules and vials.

[Medic09, BSN, RN, EMT-P]

Okay, we're both in ERs; which I assumed. The environment doesn't determine your rate of infusion; the urgency does. And in the ER you will certainly one day give Mag for cardiac (Torsades) or other applications.

It sounds like you already had an answer to your problem. As I said, I simplify it. If I have to gtt for 10 minutes or more anyway, then diluting in 50cc or more is almost always a good way to go. Makes the gtt easier to set up and track.

We mix drugs pretty often. In-house; but even more outside. Somehow our Mag is always in premix bags, except in the ACLS kit. I transport a fair number of preterm labors from smaller, outlying communities; and most of them have Mag hanging already in a premix bag.

Maybe ask your ER manager if they'd like to make a change?

[bluefabian]

I am working tomorrow, so I'll pester the pharmacy.

So far no Mg for torsades de pointes at least in my experience (Although it is taught in ACLS).

Thanks for the reply. That's why I love these forums.