Question

A physician orders intravenous cefotetan 1 g in NS to be administered as a continuous infusion over 30 minutes. You have in stock 1 g vials of cefotetan dry powder.

a) The instructions state that reconstituting the 1 g vial with 2 mL of NS results in a 400 mg/mL solution. What is the total volume of reconstituted solution in the vial? Round your final answer to the nearest tenth.

b) What is the powder volume in this vial? Round your final answer to one decimal place.

c) After reconstituting as described above, how much additional NS must be added to the solution from the vial to give a final concentration of 20 mg/mL cefotetan in the solution for infusion? Round your answer to the nearest tenth?

d) Using an infusion set that will deliver 12 gtt/mL, what drip rate will you set to administer the diluted solution from part

Answer 1

a. 1gm of cefotetan when reconstituted with 2 ml on NS it results in 400mg/ ml

Each 1 ml = 400 mg

Then 2 ml = 800 mg

So total volume of reconstituted solution in vial is 800 mg

b. Powder volume in this vial is 1gm

c. After reconstitution with 2 ml of NS each ml contain 400 mg of cefotetan

Now to make each ml 20 mg

400 mg = 1 ml

20 mg = ?

400/20 = 20 ml

So 20 ml of NS to be added to make each ml 20 mg.

d. Total 2.5 ml of NS is added to make 1gm of cefotetan

Using 12gtt/ ml

Acc.to formula = 2.5*12/30 = 30/30 = 1 drop/mt

So in infusion set 1drip rate should be set.