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NurseDive Free Nursing Practice Question
A nurse is preparing to administer tobramycin 3 mg/kg/day IM in three divided doses to a client who weighs 85 kg. The amount available is tobramycin 40 mg/ml. How many mL should the nurse administer per dose? (Round the answer to the nearest tenth. Use a leading zero if it applies. Do not use a trailing zero.)
This question is an excerpt from Nurse Dive's nursing test bank - Dosage calculations RN adult medical surgical assessment 3.1 proctored exam. Take the full exam now
Full Explanation
To calculate the amount of tobramycin to administer per dose, you need to follow these steps:
Step 1: Calculate the total daily dose. Total Daily Dose (mg) = Weight (kg) x Dose (mg/kg/day)
Total Daily Dose (mg) = 85 kg x 3 mg/kg/day = 255 mg/day
Step 2: Calculate the dose per divided dose (three divided doses). Dose per Divided Dose (mg) = Total Daily Dose (mg) / Number of Divided Doses
Dose per Divided Dose (mg) = 255 mg / 3 doses = 85 mg/dose
Step 3: Convert the dose to mL using the concentration. Dose (mL) = Dose (mg) / Concentration (mg/mL)
Dose (mL) = 85 mg / 40 mg/mL ≈ 2.125 mL
Rounded to the nearest tenth, the nurse should administer 2.1 mL per dose.
Similar Questions
A nurse is preparing to administer fentanyl 0.5 mcg/kg via IV bolus to a client who weighs 187 lb. Available is fentanyl 50 mcg/ml. How many mi should the nurse administer? (Round the answer to the nearest tenth. Use a leading zero if it applies. Do not use a trailing zero.)
Full Explanation
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Convert the client’s weight from pounds to kilograms:
- 1 kilogram (kg) = 2.2 pounds (lb)
- Weight in kg = 187 lb / 2.2 = 85 kg
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Calculate the dose of fentanyl in micrograms (mcg):
- Dose = 0.5 mcg/kg × 85 kg = 42.5 mcg
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Determine the volume of fentanyl to administer:
- Available concentration is 50 mcg/ml
- Volume (ml) = Dose (mcg) / Concentration (mcg/ml)
- Volume (ml) = 42.5 mcg / 50 mcg/ml = 0.85 ml
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Round the answer to the nearest tenth:
- Rounded volume = 0.9 ml
A nurse is preparing to administer promethazine 25 mg IM to a client. Available is promethazine 50 mg/ml. How many ml administer? (Round the answer to the nearest tenth. Use a leading zero if it applies. Do not use a trailing zero)
Full Explanation
To calculate the volume (mL) needed to administer 25 mg of promethazine using a concentration of 50 mg/mL, you can use the following formula:
Volume (mL) = Dose (mg) / Concentration (mg/mL)
In this case, the dose is 25 mg, and the concentration is 50 mg/mL:
Volume (mL) = 25 mg / 50 mg/mL = 0.5 mL
So, the nurse should administer 0.5 mL of promethazine.
A nurse is preparing to administer amiodarone 300 mg IV bolus over 10 min to a client. Available is amiodarone 50 mg/mL. 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.)
Full Explanation
To calculate the volume (mL) needed to administer 300 mg of amiodarone using a concentration of 50 mg/mL, you can use the following formula:
Volume (mL) = Dose (mg) / Concentration (mg/mL)
In this case, the dose is 300 mg, and the concentration is 50 mg/mL:
Volume (mL) = 300 mg / 50 mg/mL = 6 mL
So, the nurse should administer 6 mL of amiodarone.