Question

You are given a vial of 4mEq/mL (234 mg/mL) NaCl. You are also given a 50mL bag of NS.

How would you prepare this order? In other words, how many mL of the NaCl would you inject into the NS?

Answer 1

Given 4 mEq/ml of NaCl

We have to prepare 50 ml of normal saline. Normal saline is 0.9% NaCl which is 154 mEq/1000 ml

We have to prepare normal saline in 50 ml

so 154 mEq / 1000 ml = how much milliequivalent of saline to make 50 ml / 50 ml

= 154 / 1000 x 50 = 7.7 mEq of saline are needed to make normal saline of 50 ml.

4 mEq / ml = 7.7 mEq / x ( volume required)

x= 7.7 / 4 = 1.925 ml.

Hence 1.925 ml of 4 mEq/ml NaCl is diluted with 50 ml of sterile water to make 50 ml bag of NS.