A nurse is preparing to administer foscarnet 60 mg/kg via intermittent IV bolus to a client who weighs 126 lb. Available is foscarnet 6,000 mg in 500 mL of 0.9% sodium chloride solution. How many ml should the nurse administer? (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 solve this dosage calculation problem, follow these steps:
Step 1: Convert the client’s weight from pounds to kilograms.
- The formula for converting pounds to kilograms is: Weight in kilograms=Weight in pounds2.2\text{Weight in kilograms} = \frac{\text{Weight in pounds}}{2.2}Weight in kilograms=2.2Weight in pounds So, the client’s weight in kilograms is: 126 lb2.2=57.27 kg≈57.3 kg\frac{126 \text{ lb}}{2.2} = 57.27 \text{ kg} \approx 57.3 \text{ kg}2.2126 lb=57.27 kg≈57.3 kg
Step 2: Determine the prescribed dose in milligrams.
The order is for 60 mg/kg, and the client weighs 57.3 kg. To calculate the total dose of foscarnet:Dose=60 mg/kg×57.3 kg=3,438 mg\text{Dose} = 60 \text{ mg/kg} \times 57.3 \text{ kg} = 3,438 \text{ mg}Dose=60 mg/kg×57.3 kg=3,438 mg
Step 3: Determine the concentration of the available solution.
You have 6,000 mg of foscarnet in 500 mL of 0.9% sodium chloride solution. To find the concentration (mg/mL):Concentration=6,000 mg500 mL=12 mg/mL\text{Concentration} = \frac{6,000 \text{ mg}}{500 \text{ mL}} = 12 \text{ mg/mL}Concentration=500 mL6,000 mg=12 mg/mL
Step 4: Calculate the volume of the solution to be administered.
Using the concentration of the available solution, we can calculate the volume to be administered:Volume (mL)=Prescribed dose (mg)Concentration (mg/mL)\text{Volume (mL)} = \frac{\text{Prescribed dose (mg)}}{\text{Concentration (mg/mL)}}Volume (mL)=Concentration (mg/mL)Prescribed dose (mg) Volume (mL)=3,438 mg12 mg/mL=286.5 mL≈287 mL\text{Volume (mL)} = \frac{3,438 \text{ mg}}{12 \text{ mg/mL}} = 286.5 \text{ mL} \approx 287 \text{ mL}Volume (mL)=12 mg/mL3,438 mg=286.5 mL≈287 mL
Final Answer:
The nurse should administer 287 mL of the foscarnet solution.
Explanation:
In this problem, the nurse must administer foscarnet based on the client’s weight. First, the client’s weight is converted from pounds to kilograms to match the dosage calculation in mg/kg. The prescribed dose is then calculated by multiplying the dose per kilogram by the client’s weight in kilograms. Once the total dose in milligrams is determined, the next step is to determine how many milliliters of the available solution are needed to provide this dose. The available solution concentration (12 mg/mL) is used to divide the total prescribed dose, giving the final volume in milliliters. This ensures the nurse administers the correct amount of medication safely. The rounding rules ensure the result is in a practical format for administration.