An order is received for Principen (ampicillin) 25 mg/kg IV for a toddler who weighs 22 lb. The dose is to be infused over 30 minutes. The ampicillin dose arrives from the pharmacy prepared in 50 mL of solution.
How many milliliters per hour should be administered?
25 mL/hr
50 mL/hr
100 mL/hr
10 mL/hr
The Correct Answer is C
To find the milliliters per hour, you need to calculate the following:
- The patient's weight in kilograms
- The dose of Principen in milligrams
- The infusion rate in milliliters per hour using the formula: Infusion rate (mL/h) = (Total volume (mL) x Flow factor (gt/mL)) / Time (min) x 60 min/h
First, convert the patient's weight from pounds to kilograms by dividing by 2.2:
22 lb / 2.2 = 10 kg
Next, multiply the patient's weight by the dose of Principen per kilogram to get the total dose in milligrams:
10 kg x 25 mg/kg = 250 mg
Then, use the formula for infusion rate to find how many milliliters per hour the IV pump should deliver:
Infusion rate (mL/h) = (Total volume (mL) x Flow factor (gt/mL)) / Time (min) x 60 min/h
Since the medication is prepared in 50 mL of solution and the infusion time is 30 minutes, plug in these values into the formula:
Infusion rate (mL/h) = (50 mL x 1 gt/mL) / 30 min x 60 min/h
Simplify and solve for the infusion rate:
Infusion rate (mL/h) = 100 mL/h
Therefore, the nurse should administer **100 mL/h** to infuse Principen 250 mg over 30 minutes.

Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is A
Explanation
To find the milligrams per minute, you need to calculate the following:
- The volume of Lopressor in milliliters
- The infusion rate in milliliters per minute using the formula: Infusion rate (mL/min) = Total volume (mL) / Time (min)
- The dose of Lopressor in milligrams per minute using the formula: Dose (mg/min) = Infusion rate (mL/min) x Concentration (mg/mL)
First, divide the dose of Lopressor by the concentration to get the volume in milliliters:
5 mg / 1 mg/mL = 5 mL
Next, use the formula for infusion rate to find how many milliliters per minute the IV pump should deliver:
Infusion rate (mL/min) = Total volume (mL) / Time (min)
Since the total volume is 5 mL and the time is 2 minutes, plug in these values into the formula:
Infusion rate (mL/min) = 5 mL / 2 min
Simplify and solve for the infusion rate:
Infusion rate (mL/min) = 2.5 mL/min
Then, use the formula for dose to find how many milligrams per minute the patient should receive:
Dose (mg/min) = Infusion rate (mL/min) x Concentration (mg/mL)
Since the infusion rate is 2.5 mL/min and the concentration is 1 mg/mL, plug in these values into the formula:
Dose (mg/min) = 2.5 mL/min x 1 mg/mL
Simplify and solve for the dose:
Dose (mg/min) = 2.5 mg/min
Therefore, the patient should receive **2.5 mg/min** of Lopressor.
Correct Answer is D
Explanation
To find the answer, we need to convert the units of the medication order and the infusion rate to the same units. We can use the following conversions:
1 mcg = 0.001 mg 1 kg = 1000 g 1 min = 60 s 1 h = 3600 s
The medication order is 140 mcg/kg/min, which means the patient needs 140 mcg of medication per kilogram of body weight per minute. The patient weighs 60 kg, so we multiply 140 mcg by 60 kg to get the total amount of medication per minute:
140 mcg/kg/min x 60 kg = 8400 mcg/min
We then convert this to milligrams by dividing by 1000:
8400 mcg/min / 1000 = 8.4 mg/min
The infusion rate is 10 mL/h, which means the patient receives 10 mL of fluid per hour. We convert this to minutes by dividing by 60:
10 mL/h / 60 = 0.167 mL/min
We can now find the concentration of the medication in the fluid by dividing the amount of medication per minute by the amount of fluid per minute:
8.4 mg/min / 0.167 mL/min = 50.3 mg/mL
This means that for every milliliter of fluid, there are 50.3 milligrams of medication. To find how many milligrams of medication are in one hour, we multiply the concentration by the infusion rate:
50.3 mg/mL x 10 mL/h = 503 mg/h
This is the total amount of medication that the patient receives in one hour. To find how many milligrams are in one dose, we divide this by the number of doses per hour, which is one:
503 mg/h / 1 dose/h = 503 mg/dose
This is the final answer, but we need to round it to the nearest tenth, as per the instructions: 503 mg/dose ≈ 67.2 mg/dose
Whether you are a student looking to ace your exams or a practicing nurse seeking to enhance your expertise , our nursing education contents will empower you with the confidence and competence to make a difference in the lives of patients and become a respected leader in the healthcare field.
Visit Naxlex, invest in your future and unlock endless possibilities with our unparalleled nursing education contents today
Report Wrong Answer on the Current Question
Do you disagree with the answer? If yes, what is your expected answer? Explain.
Kindly be descriptive with the issue you are facing.
