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A nurse is preparing to administer phenobarbital 2 mg/kg/day IV divided in 2 equal doses to a client who weighs 165 lb. Available is phenobarbital 65 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 mL of phenobarbital to administer per dose, you can use the following steps:
Convert the client's weight from pounds to kilograms. There are approximately 2.2 pounds in 1 kilogram.
Weight in kg = 165 lb / 2.2 lb/kg ≈ 75 kg
Calculate the total daily dose based on the client's weight and the prescribed dose per kilogram:
Total daily dose = 2 mg/kg/day × 75 kg ≈ 150 mg/day
Since the dose is divided into two equal doses per day, calculate the dose per dose:
Dose per dose = Total daily dose / 2 = 150 mg / 2 = 75 mg
Now, you need to find out how many mL of phenobarbital 65 mg/mL corresponds to a dose of 75 mg:
Volume (mL) = Dose (mg) / Concentration (mg/mL) = 75 mg / 65 mg/mL ≈ 1.1538 mL
Rounded to the nearest tenth, the nurse should administer approximately 1.2 mL of phenobarbital per dose.
Similar Questions
A nurse is caring for a client who reports taking 1 Tbsp of guaifenesin oral solution every 4 hr. The concentration on the client's bottle reads guaifenesin 100 mg/5 mL. How many mg of guaifenesin is the client taking with each dose? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)
Full Explanation
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Convert tablespoons to milliliters:
- 1 tablespoon (Tbsp) = 15 mL
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Determine the concentration of guaifenesin:
- The concentration is 100 mg per 5 mL
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Calculate the amount of guaifenesin per 1 tablespoon (15 mL):
- First, find out how many milligrams are in 1 mL:
- 100 mg / 5 mL = 20 mg/mL
- Then, multiply by 15 mL:
- 20 mg/mL × 15 mL = 300 mg
- First, find out how many milligrams are in 1 mL:
So, the client is taking 300 mg of guaifenesin with each dose.
A nurse is caring for a client who reports taking 1 Tbsp of guaifenesin oral solution every 4 hr. The concentration on the client's bottle reads guaifenesin 100 mg/5 mL. How many mg of guaifenesin is the client taking with each dose? (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 how many milligrams (mg) of guaifenesin the client is taking with each dose, you can use the following steps:
Determine the volume of the client's dose. The client is taking 1 tablespoon (Tbsp) of guaifenesin oral solution.
1 Tbsp is approximately equal to 15 mL.
Determine the concentration of guaifenesin in the oral solution, which is 100 mg/5 mL.
Calculate the amount of guaifenesin in the client's dose:
Amount (mg) = (Volume of dose in mL / Concentration in mg/mL)
Amount (mg) = (15 mL / 5 mg/mL) = 3 doses of 100 mg each
So, the client is taking 300 mg of guaifenesin with each dose.
A nurse is preparing to administer pyrazinamide 20 mg/kg PO to a client who weighs 165 lb and has tuberculosis. Available is pyrazinamide 500 mg tablets. How many tablets 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 how many tablets of pyrazinamide the nurse should administer, you can use the following steps:
Convert the client's weight from pounds (lb) to kilograms (kg):
Client's weight in kg = Client's weight in lb / 2.2 Client's weight in kg = 165 lb / 2.2 ≈ 75 kg
Determine the total dosage required based on the client's weight:
Total dosage = Client's weight in kg × Dosage (mg/kg) Total dosage = 75 kg × 20 mg/kg = 1500 mg
Determine the number of tablets needed:
Number of tablets = Total dosage / Tablet strength Number of tablets = 1500 mg / 500 mg/tablet = 3 tablets
The nurse should administer 3 tablets of pyrazinamide