Question

Preparation #2: Ranitidine 125 mcg/kg Infusion Patient weight: 158.4-lbs For stress ulcer prophylaxis, maintenance dose of 125 mcg/kg every 6 hours. Ranitidine 25 mg/mL Injection Solution (25 ml vial) D5W Injection Solution (100-ml IV bag) Total Volume - 100-ml 100-ml Supplies needed: Sterile needles and syringes Procedure: 1. Calculate the required quantity of each ingredient 2. Weigh and/or measure each ingredient accurately 3. Using aseptic technique, withdraw a volume from the 100-ml bag of NS equal to the volume of ranitidine injection solution to be transferred to the IV bag. 4. Using a new needle and syringe, aseptically withdraw the calculated quantity of ranitidine injection solution and transfer to the IV bag. 5. Mix well 6. Cover injection port with a tamper seal. Calculations: Calculate the quantity of ranitidine injection solution for this medication order. 158.4 lbs x 1kg = 72kg If the recommended final concentration of ranitidine infusion should not exceed 0.5- mg/mL, does this preparation meet that recommendation or should it be diluted in a larger volume of D5W?

Answer 1

Order dose 125mcg/kg

Patient weight 158.4 lbs. (I.e 72kg)

So, total medication needed for the patient is

125mcg x 72kg = 9000mcg

It means 9 mg of ranitidine required for the patient in every 6 hours.

The total volume of Drug is 100 ml (Consists 25mg of ranitidine and D5W)

Then

100ml: 25,000mcg x 9000mcg = 36ml

So we have to administer 36ml of solution

Recommended final concentration should not exceed 0.5mg/ml means 500mcg/ml

But in our concentration there is

9000mcg + 36ml = 250mcg/ml

So, no need to do nothing.