A nurse is preparing to administer ceftriaxone 250 mg IM to an adult client who has a gonococcal infection. The label on the vial indicates to reconstitute each vial with sterile water 2.1 mL to yield ceftriaxone 350 mg/mL. How many mL of the reconstituted medication should the nurse administer? (Round the answer to the nearest hundredth. Use a leading zero if it applies. Do not use a trailing zero.)
The correct answer and Explanation is :
To determine how many mL of the reconstituted medication the nurse should administer, follow these steps:
- Understand the Problem:
- You need to administer 250 mg of ceftriaxone IM.
- The vial is reconstituted to a concentration of 350 mg/mL.
- You need to find out how many mL of this reconstituted solution contains 250 mg of ceftriaxone.
- Set Up the Calculation:
Use the formula:
[
\text{Volume to administer (mL)} = \frac{\text{Desired Dose (mg)}}{\text{Concentration (mg/mL)}}
]
- Desired Dose = 250 mg
- Concentration = 350 mg/mL
- Calculate the Volume:
[
\text{Volume to administer} = \frac{250 \text{ mg}}{350 \text{ mg/mL}}
]
[
\text{Volume to administer} = 0.7143 \text{ mL}
] Rounding to the nearest hundredth:
[
0.7143 \approx 0.71 \text{ mL}
] - Explanation:
- First, you need to reconstitute the ceftriaxone vial by adding sterile water. According to the vial’s label, adding 2.1 mL of sterile water will result in a solution with a concentration of 350 mg/mL.
- To administer 250 mg of ceftriaxone, you calculate the volume of the reconstituted solution required by dividing the desired dose (250 mg) by the concentration of the solution (350 mg/mL).
- The result is approximately 0.7143 mL. When rounded to the nearest hundredth, this is 0.71 mL.
So, the nurse should administer 0.71 mL of the reconstituted ceftriaxone solution.