Question

A) You need to administer insulin by continuous I.V. infusion at 12 units/hr. You hang a bag of insulin solution on the IV pump. The bag contains 150 units of insulin within 300 mL of normal saline. What rate on the infusion pump (mL/hr) will deliver the correct dose?

B) You start this insulin infusion right at the beginning of your 12 hour shift. As you are giving report to the next nurse to come work with the patient (12 hours from start of insulin drip), how long should you tell him/her they will have until the infusion bag is empty?

Answer 1

A) 300 ml of normal saline contains 150 units of insulin. Therefore, each ml of normal saline contains 0.5 ml of insulin.

We need to administer 12 units per hour. So, 24 ml of normal saline is to be administered in an hour. (24 ml/hour).

B) In one hour, 24 ml is being infused. Therefore, in 12 hours 288 ml will be used up. The remaining 12 ml requires 30 minutes.