Using the insulin infusion protocol with BG 312 mg/dL, a pre-mixed bag of 100 units in 100 mL NS, what is the infusion rate in mL/hr?

• A. 1
• B. 2
• C. 4
• D. 6

Answer: (C)

The key idea is converting the insulin amount to a flow rate using the bag’s concentration. The pre-mixed bag contains 100 units in 100 mL, so the solution is 1 unit per mL. A common insulin infusion starting rate for hyperglycemia is about 0.1 unit per kilogram per hour. If the patient weighs around 40 kg, that equals 4 units per hour. With a concentration of 1 unit per mL, delivering 4 units per hour means the infusion rate is 4 mL per hour. Therefore, the correct rate is 4 mL/hr. Delivering 1, 2, or 6 mL/hr would correspond to 1, 2, or 6 units per hour, which do not match the typical starting dose for this scenario.