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Dosage calculations RN Ati adult medical surgical proctored assessment 3.1
Total Questions : 35
Showing 10 questions, Sign in for moreA nurse is reviewing medications prescribed for a client. For which of the following prescriptions should the nurse contact the provider for clarification?
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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.)
Explanation
To calculate the dosage of tobramycin for a client who weighs 85 kg, the nurse should first determine the total daily dose by multiplying the weight by the prescribed dose per kg.
This gives 3 mg/kg/day x 85 kg = 255 mg/day.
Next, the nurse should divide the total daily dose by the number of doses per day to get the dose per administration.
This gives 255 mg/day / 3 doses/day = 85 mg/dose.
Finally, the nurse should use the formula D/H x Q to find the volume to be administered, where D is the desired dose, H is the dose on hand, and Q is the quantity on hand.
This gives 85 mg/dose / 40 mg/mL x 1 mL = 2.125 mL/dose.
Therefore, the nurse should administer 2.1 mL of tobramycin per dose to the client.
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A nurse is preparing to administer cefazolin 1 g intermittent IV bolus in 0.9% sodium chloride 250 mL over 30 min. The drop factor on the manual IV tubing is 10 gtt/mL. The nurse should set the manual IV flow rate to deliver how many gtt/min? (Round the answer to the nearest whole number. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
To calculate the manual IV flow rate, the nurse needs to use the following formula:
Flow rate (gtt/min) = Volume (mL) x Drop factor (gtt/mL) / Time (min)
Plugging in the given values, we get:
Flow rate (gtt/min) = 250 mL x 10 gtt/mL / 30 min
Flow rate (gtt/min) = 2500 gtt / 30 min
Flow rate (gtt/min) = 83.33 gtt/min
The nurse should set the manual IV flow rate to deliver 83 gtt/min.
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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 mL should the nurse administer? (Round the answer to the nearest tenth. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
To calculate the dose of fentanyl for a client who weighs 187 lb, the nurse needs to convert the weight to kilograms and multiply it by the prescribed dose of 0.5 mcg/kg.
One kilogram is equal to 2.2 lb, so the client's weight in kilograms is 187 / 2.2 = 85 kg.
The dose of fentanyl in micrograms is 85 x 0.5 = 42.5 mcg.
The nurse then needs to divide the dose in micrograms by the concentration of fentanyl in the available solution, which is 50 mcg/mL.
The volume of fentanyl in milliliters is 42.5 / 50 = 0.85 mL.
The nurse should round the answer to the nearest tenth, so the final answer is 0.9 mL.
The nurse should administer 0.9 mL of fentanyl via IV bolus to the client.
A nurse is preparing to administer lisinopril 2.5 mg PO to an older adult client. Available is lisinopril 5 mg tablets. How many tablets should the nurse administer? (Round the answer to the nearest tenth. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
To give the correct dose of lisinopril to an older adult client, the nurse needs to calculate the number of tablets to administer. The formula for this calculation is:
(number of tablets) = (desired dose) / (available dose)
In this case, the desired dose is 2.5 mg and the available dose is 5 mg. Plugging these values into the formula, we get:
(number of tablets) = (2.5 mg) / (5 mg)
Simplifying the fraction, we get:
(number of tablets) = 0.5
This means that the nurse should administer half a tablet of lisinopril 5 mg to the older adult client.
A nurse is preparing to administer exenatide 10 mcg subcutaneous. Available is exenatide 250 mcg/mL. How many mL should the nurse administer? (Round the answer to the nearest hundredth. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
o calculate the dose of exenatide, the nurse should use the following formula:
Dose (mL) = Desired dose (mcg) / Available dose (mcg/mL)
Plugging in the values from the question, we get:
Dose (mL) = 10 mcg / 250 mcg/mL
Dose (mL) = 0.04 mL
The nurse should administer 0.04 mL of exenatide subcutaneously.
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.)
Explanation
To calculate the dose of ceftriaxone for an adult client with a gonococcal infection, the nurse needs to use the following formula: Dose (mL) = Ordered dose (mg) / Available dose (mg/mL).
In this case, the ordered dose is 250 mg and the available dose is 350 mg/mL.
Therefore, the nurse should administer 250 / 350 = 0.71 mL of the reconstituted medication.
The answer should be rounded to the nearest hundredth, so the final answer is 0.71 mL.
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.)
Explanation
To calculate the dose of phenobarbital for this client, the nurse needs to convert the client's weight from pounds to kilograms.
One kilogram is equal to 2.2 pounds, so the nurse can divide 165 by 2.2 to get 75 kg.
Next, the nurse needs to multiply the client's weight by the prescribed dose of 2 mg/kg/day to get the total daily dose of phenobarbital.
This is 75 x 2 = 150 mg/day.
Since the dose is divided in 2 equal doses, the nurse needs to divide 150 by 2 to get the amount of phenobarbital per dose. This is 75 mg/dose.
Finally, the nurse needs to use the available concentration of phenobarbital to determine how many mL to administer per dose.
Calculate the volume of phenobarbital to administer: 75mg ÷ 65 mg/mL = 1.15 mL
Therefore, the nurse should administer 1.15 mL of phenobarbital per dose. Rounded off is 1.2ml.
Therefore, the nurse should administer 1.2 mL of phenobarbital per dose.
A nurse is preparing to administer prednisone 15 mg PO to a client who has rheumatoid arthritis. Available is prednisone 10 mg tablets. How many tablets should the nurse administer? (Round the answer to the nearest tenth. Use a leading zero if it applies. Do not use a trailing zero.)
Explanation
To calculate the dosage of prednisone for a client with rheumatoid arthritis, the nurse needs to apply the formula: D/H x Q = X, where D is the desired dose, H is the dose on hand, Q is the quantity, and X is the amount to administer.
In this case, D is 15 mg, H is 10 mg, and Q is 1 tablet.
Plugging these values into the formula, we get: 15/10 x 1 = 1.5.
Therefore, the nurse should administer 1.5 tablets of prednisone to the client.
A nurse is preparing to administer metronidazole 7.5 mg/kg via intermittent IV bolus to a client who weighs 212 lb. Available is metronidazole 500 mg/100 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.)
Explanation
First, let's convert the client's weight from pounds to kilograms: 212 lb / 2.2 lb/kg ≈ 96.36 kg
Next, calculate the total dose of metronidazole: 7.5 mg/kg * 96.36 kg ≈ 727 mg
Now, let's determine how many milliliters of the available metronidazole solution (500 mg/100 mL) contains the prescribed dose of 727 mg: (727 mg / 500 mg) * 100 mL = 145.4 mL
Rounded to the nearest whole number, the nurse should administer approximately 145 mL of metronidazole.
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