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DOSAGE CALCULATION RN FUNDAMENTALS PROCTORED ASSESMENT
Total Questions : 27
Showing 10 questions, Sign in for moreA nurse is preparing to administer phenytoin 200 mg PO to a client. Available is phenytoin oral suspension 125 mg/5 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
To calculate the dose of phenytoin oral suspension, the nurse should use the following formula:
Dose (mL) = Desired dose (mg) / Concentration (mg/mL) x Volume (mL)
Plugging in the values from the question, we get:
Dose (mL) = 200 mg / 125 mg/5 mL x 5 mL
Simplifying the equation, we get:
Dose (mL) = 8 mL
A nurse is preparing to administer morphine 0.2 mg/kg IM to a child who weighs 77 lb. Available is morphine injection 10 mg/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 dosage of morphine for a child, the nurse needs to convert the child's weight from pounds to kilograms and then multiply it by the prescribed dose per kilogram. The nurse also needs to divide the resulting amount by the concentration of the morphine injection to get the volume to be administered. The formula is:
Volume (mL) = (Weight (kg) x Dose (mg/kg)) / Concentration (mg/mL)
In this case, the child weighs 77 lb, which is equivalent to 35 kg (77 / 2.2 = 35). The prescribed dose is 0.2 mg/kg and the concentration of the morphine injection is 10 mg/mL. Therefore, the volume to be administered is:
Volume (mL) = (35 x 0.2) / 10
Volume (mL) = 0.7
The nurse should round the answer to the nearest tenth, which is 0.7 mL.
A nurse is preparing to administer lorazepam 50 mcg/kg IM to a client who weighs 176 lb. Available is lorazepam 4 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.)
Explanation
This is a question that tests the nurse's ability to calculate drug dosages based on the client's weight and the drug concentration. To solve this problem, the nurse needs to follow these steps:
1. Convert the client's weight from pounds to kilograms by dividing by 2.2. 176 lb / 2.2 = 80 kg.
2. Multiply the client's weight in kilograms by the prescribed dose in micrograms per kilogram to get the total dose in micrograms. 80 kg x 50 mcg/kg = 4000 mcg.
3. Convert the total dose in micrograms to milligrams by dividing by 1000. 4000 mcg / 1000 = 4 mg.
4. Divide the total dose in milligrams by the drug concentration in milligrams per milliliter to get the volume in milliliters. 4 mg / 4 mg/mL = 1 mL.
5. Round the answer to the nearest whole number and add a leading zero if it applies. Do not use a trailing zero. The final answer is 1 mL.
Therefore, the nurse should administer 1 mL of lorazepam IM to the client.
A nurse is preparing to administer diclofenac sodium 200 mg PO daily in equally divided doses every 6 hr. How many mg should the nurse administer per dose? (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 dose of diclofenac sodium per administration, the nurse should divide the total daily dose by the number of doses per day.
In this case, the total daily dose is 200 mg and the number of doses per day is 4 (every 6 hr).
Therefore, the dose per administration is 200 mg / 4 = 50 mg.
The nurse should administer 50 mg of diclofenac sodium PO every 6 hr.
A nurse is preparing to administer methylprednisolone acetate 60 mg IM. Available is methylprednisolone acetate injection 80 mg/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
To calculate the dose of methylprednisolone acetate injection, the nurse should use the following formula:
Dose (mL) = Desired dose (mg) / Available dose (mg/mL)
Plugging in the values from the question, we get:
Dose (mL) = 60 mg / 80 mg/mL
Dose (mL) = 0.75 mL
A nurse is preparing to administer cefazolin 250 mg IM to a client. Available is cefazolin powder for injection 500 mg vial. The nurse reconstitutes the powder with 2 mL of sterile water for a concentration of 225 mg/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 dosage of cefazolin, the nurse needs to use the formula D/H x Q, where D is the desired dose, H is the dose on hand, and Q is the quantity.
In this case, D is 250 mg, H is 225 mg/mL, and Q is 1 mL.
Plugging these values into the formula, we get:
250 mg / 225 mg/mL x 1 mL = 1.11 mL
Therefore, the nurse should administer 1.1 mL of cefazolin IM to the client.
A nurse on a pediatric unit is implementing a prescription for dexamethasone solution 0.3 mg/kg now. Which of the following additional Information should the nurse have to interpret this prescription and administer this medication? (Select all that apply.)
A nurse is preparing to administer isoniazid 187 mg IM. Available is isoniazid injection 100 mg/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 dosage of isoniazid injection, the nurse should use the formula D/H x Q, where D is the desired dose, H is the dose on hand, and Q is the quantity.
In this case, D is 187 mg, H is 100 mg/mL, and Q is 1 mL.
Plugging these values into the formula, we get:
187 mg / 100 mg/mL x 1 mL = 1.87 mL
To round the answer to the nearest tenth, the final answer is: 1.9 mL
The nurse should administer 1.9 mL of isoniazid injection to the patient.
A nurse is preparing to administer diazepam 10 mg IM stat to a client. Available is diazepam injection 5 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.)
Explanation
To calculate the dosage of diazepam, the nurse needs to use the formula D/H x Q, where D is the desired dose, H is the dose on hand, and Q is the quantity.
In this case, D is 10 mg, H is 5 mg/mL, and Q is 1 mL.
Plugging these values into the formula, we get:
10 mg / 5 mg/mL x 1 mL = 2 mL
Therefore, the nurse should administer 2 mL of diazepam injection to the client.
A nurse is preparing to administer quinapril 20 mg PO Available is quinapril 40 mg tablets. How many tablets should 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 quinapril, 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 of the drug, and X is the amount to administer.
In this case, D = 20 mg, H = 40 mg, Q = 1 tablet, and X is unknown.
Plugging in the values, we get: 20/40 x 1 = X.
Simplifying, we get: 0.5 = X.
Therefore, the nurse should administer 0.5 tablets of quinapril.
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