Mr Chifley Returns to the Ward Three Hours Later and Two

Short Answer

Mr Chifley returns to the ward three hours later and two registered nurses are setting up an infusion to control his pain. His pain relief medication is to be delivered via a secondary line in a volumetric pump. He is to have 300 mg of pethidine in 100 ml of 0.9% sodium chloride, and this solution is to infuse over a 20-hour period. You have been asked to assist by working out the nursing calculations required for this task.
-What is the concentration, in mg/ml, of this medicated solution?