mEq Question help

[Apple-Core, ASN, BSN, RN]

Hi -

I have never worked with Milliequivalents before, or even heard of them...! That being said, I am hoping someone can critique my answer, please:

Order is for K+ elixier 30mEq po

On hand is K+ elixier 20mEq/one oz.

How many mL will you administer?

I did the following:

On hand is 20mEq/1 oz.

Therefore 30mEq/1.5oz.

1 oz = 29.6mL (rounded to the tenths place)

Therefore 1.5 oz = 29.6 X 1.5 = 44.4

Answer = 44.4mL

Is this correct, and furthermore...what in the diddlysquits is a Milliequivalent ...LOL!??

Thanks!

[KelRN215, BSN, RN]

Everywhere I've ever worked, 1 oz = 30 mL so your dose would be 45 mL. You did the math correctly, though.

A milliequivalent is a fairly standard way of measuring electrolytes. It is 1/1000 of the equivalent weight of the element or compound.

[bgxyrnf, MSN, RN]

From the viewpoint of solving these problems, equivalents (mEq) can be treated the same as mass (mg).

[Apple-Core, ASN, BSN, RN]

Thank you both!

[bjwojcik]

This might help explain what a mEq is.

Key Concepts to Understanding Milliequivalent Calculations

mEq calculations involve quantities of ions and charges, not weights. Think dozens of eggs, not pounds of coffee beans.

A millimole (mmole) is 1/1000 of a mole (mol) or 6.022 X 10^20 of anything.

A mEq is a mmol of charges.

Examples:

1 mmol of NaCl = 1 mmol of Na+ and 1 mmol of Cl-.

Na+ and Cl- each have one charge.

1 mmol of NaCl = 1 mEq of Na+ and 1 mEq Cl-.

1 mmol of MgSO4 = 1 mmol of Mg+2 and 1 mmol of SO4-2.

Mg+2 and SO4-2 each have two charges.

1 mmol of MgSO4 = 2 mEq of Mg+2 and 2 mEq of SO4-2.

Brad Wojcik, PharmD