Question

An order calls for 6 grams of magnesium sulfate added to 500mL of NS infused at a rate of 1 g/hr. You have available 50%w/v magnesium sulfate vials. What is the infusion rate in mL/hr? Please round the final answer to the nearest whole number.

Answer 1

6gram of magnesium sulfate added to 500 ml of NS infused at a rate of 1gm/hr

Available magnesium sulfate (50%) 10gm/20ml

Magnesium sulfate available 10gm, then to calculate 6 gram from that

Desired

--------------× ml

Available

6gram

--------------× 20ml= 12ml

10gm

12ml mixed in 500 ml intravenous solution

Step 1

Then to calculate the units per liter by dividing actual amount of medication with total volume of diluent

Actual amount of medication

--------------------------------------

Total volume of diluent

       6gm

---------------- ==0.012 per milliliter

         500

Step 2: calculate milliliter per hour

   Required dose per hour

-----------------------------------

Concentration per milliliter

    1gm

--------------= 83.33 ml per hour

0.012 per mililiter

The number nearest whole number =83 ml per hour