A nurse is preparing to administer 40 mEq of potassium chloride in 45% sodium chloride (NaCl) 500 mL IV to infuse 10 mEq/hr. The nurse should set the IV pump to deliver how many mL/hr? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)
The correct answer and Explanation is :
To determine how many mL/hr the IV pump should be set to deliver, follow these steps:
- Understand the infusion rate:
The nurse needs to administer 40 mEq of potassium chloride (KCl) at a rate of 10 mEq/hr. This means the total infusion rate for the potassium chloride solution must be set to deliver 10 mEq of KCl per hour. - Calculate the total volume of the IV solution:
The potassium chloride is diluted in 500 mL of 45% sodium chloride (NaCl) solution. The concentration of potassium chloride in this solution needs to be determined in mEq/mL. - Determine the concentration of KCl in the solution:
- The total amount of potassium chloride in the solution is 40 mEq.
- The total volume of the solution is 500 mL. Therefore, the concentration of KCl in the solution is:
[
\text{Concentration} = \frac{\text{Total KCl (mEq)}}{\text{Total Volume (mL)}} = \frac{40 \text{ mEq}}{500 \text{ mL}} = 0.08 \text{ mEq/mL}
]
- Calculate the infusion rate in mL/hr:
To deliver KCl at a rate of 10 mEq/hr, use the concentration to find the necessary infusion rate in mL/hr:
[
\text{Infusion Rate (mL/hr)} = \frac{\text{Desired Rate (mEq/hr)}}{\text{Concentration (mEq/mL)}} = \frac{10 \text{ mEq/hr}}{0.08 \text{ mEq/mL}} = 125 \text{ mL/hr}
]
Thus, the IV pump should be set to deliver 125 mL/hr.
Explanation:
In this scenario, you need to calculate the infusion rate based on the concentration of potassium chloride in the solution. By dividing the required infusion rate of potassium chloride (10 mEq/hr) by its concentration in the solution (0.08 mEq/mL), you determine how fast the IV pump should deliver the solution to achieve the correct dose per hour. The result, 125 mL/hr, ensures that the patient receives the prescribed amount of potassium chloride at the desired rate.