At 3 PM Vader’s pharmacist receives an order to add 30 mEq/L potassium chloride to an already running IV fluid for Lord Vader that already contains 5% dextrose and 0.9% sodium chloride. The IV infusion that started at 1:30 PM is running at a rate of 85 ml/hour. It takes the pharmacist 30 minutes to get to Vader’s room (5-7).

Question

At 3 PM Vader’s pharmacist receives an order to add 30 mEq/L potassium chloride to an already running IV fluid for Lord Vader that already contains 5% dextrose and 0.9% sodium chloride. The IV infusion that started at 1:30 PM is running at a rate of 85 ml/hour. It takes the pharmacist 30 minutes to get to Vader’s room (5-7).

1. How many milliequivalents of potassium chloride should she add to the running IV infusion?

Answer 1

To calculate the amount of potassium chloride to add to the running IV infusion, we need to consider the time elapsed since the infusion started, the rate at which the infusion is running, and the concentration of potassium chloride to be added.

Here's how you would calculate it step by step:

1. Determine the time elapsed since the infusion started: The infusion started at 1:30 PM, and we know that the pharmacist receives the order at 3 PM. Therefore, the time elapsed is 1 hour and 30 minutes (3 PM - 1:30 PM).

2. Calculate the volume of fluid that has already been infused: The infusion is running at a rate of 85 ml/hour. We can multiply this rate by the time elapsed (in hours) to determine the volume of fluid already infused. In this case, the volume is 85 mL/hour x 1.5 hours = 127.5 mL.

3. Determine the concentration of potassium chloride to be added: The pharmacist receives an order to add 30 mEq/L of potassium chloride. This means that for every liter (1000 mL) of IV fluid, 30 milliequivalents of potassium chloride should be added.

4. Calculate the amount of potassium chloride to be added: Since we have the volume of fluid already infused (127.5 mL), we can calculate the amount of potassium chloride to be added. We need to find out how much potassium chloride is needed for this volume of fluid (127.5 mL).

To do this, we can set up a proportion based on the concentration of potassium chloride to be added (30 mEq/L) and the volume of fluid already infused (127.5 mL):
(30 mEq / 1000 mL) = (x mEq / 127.5 mL)

By cross-multiplying and solving for x, we can determine that x = (30 mEq x 127.5 mL) / 1000 mL = 3.825 mEq.

Therefore, the pharmacist should add approximately 3.825 milliequivalents of potassium chloride to the running IV infusion for Lord Vader.