NCLEX: Drug Dosage Calculation Exam 8

EXPLANATION

✔Solution:

Understanding the Problem:

Nurse Butler must administer 4.5 g of piperacillin/tazobactam IV in 100 mL of 5% Dextrose in Water over 1 hour using microdrip tubing. Microdrip tubing typically delivers 60 drops per mL. The goal is to calculate the drip rate in drops per minute (gtts/min).

Step-by-Step Solution:

1. Determine the infusion rate in mL per minute:

• Total volume = 100 mL
• Total time = 1 hour = 60 minutes
• Infusion rate = 100 mL ÷ 60 minutes ≈ 1.67 mL/min

2. Convert the rate to drops per minute using the microdrip drop factor:

• Drop factor = 60 gtts/mL
• Drip rate = 1.67 mL/min × 60 gtts/mL ≈ 100 gtts/min

3. Final Answer:

• Nurse Butler should set the infusion at 100 gtts/min.

ANSWER: 100 gtts/min

Simplified recap: Divide 100 mL by 60 minutes to obtain approximately 1.67 mL/min. Multiplying 1.67 mL/min by 60 gtts/mL gives about 100 gtts/min.

EXPLANATION

✔Solution:

Understanding the Problem:

Nurse Aquino is to administer 100 mL of ceftizoxime in 5% Dextrose in Water over 30 minutes using IV tubing with a drop factor of 10 drops per mL. The goal is to determine the drip rate in drops per minute (gtts/min).

Step-by-Step Solution:

1. Calculate the infusion rate in mL per minute:

• Total volume = 100 mL
• Total time = 30 minutes
• Infusion rate = 100 mL ÷ 30 min ≈ 3.33 mL/min

2. Convert the rate to drops per minute using the drop factor:

• Drop factor = 10 gtts/mL
• Drip rate = 3.33 mL/min × 10 gtts/mL = 33.33 gtts/min

3. Rounding:

• Rounded to the nearest whole number, the drip rate is approximately 33 gtts/min.

Final Answer:

• Nurse Aquino should set the drip rate at 33 gtts/min.

ANSWER: 33 gtts/min

Simplified recap: Divide 100 mL by 30 minutes to get about 3.33 mL/min. Multiply 3.33 mL/min by 10 gtts/mL to obtain approximately 33 gtts/min.

EXPLANATION

✔Solution:

Understanding the Problem:

The patient needs to receive 15 mL of magnesium hydroxide/aluminum hydroxide oral suspension. Since the patient only has standard kitchen measuring spoons, Nurse Rodriguez must convert the 15 mL dose into tablespoons.

Step-by-Step Solution:

1. Recognize the Conversion Factor:

• 1 tablespoon = 15 mL

2. Set Up the Conversion:

• 15 mL × (1 tablespoon / 15 mL) = 1 tablespoon
• The "mL" cancels out, leaving the result in tablespoons.

3. Final Answer:

• Nurse Rodriguez should instruct the patient to take 1 tablespoon to receive 15 mL of the suspension.

ANSWER: Take 1 Tablespoon.

Simplified recap: Since 1 tablespoon is equivalent to 15 mL, the patient should use 1 tablespoon to measure the correct dose.

EXPLANATION

✔Solution:

Understanding the Problem:

Nurse Jackson must set the infusion pump to deliver morphine at a rate of 80 mg per hour. The available morphine solution contains 500 mg in 500 mL of normal saline, which means the concentration is 1 mg per mL. We need to calculate the pump rate in mL per hour that will deliver 80 mg/hr.

Step-by-Step Solution:

1. Determine the concentration:

• 500 mg in 500 mL = 1 mg/mL

2. Set up the conversion using dimensional analysis:

80 mg/hr × (1 mL / 1 mg)

• The mg cancels out, leaving the result in mL/hr.

3. Perform the calculation:

• 80 × 1 = 80 mL/hr

Final Answer:

• Nurse Jackson should set the infusion pump to 80 mL/hour.

ANSWER: 80 mL/hour

Simplified recap: With a concentration of 1 mg/mL, an 80 mg/hr order translates directly to 80 mL/hr.

EXPLANATION

✔Solution:

Understanding the Problem:

Nurse Smith must administer 225,000 units of ergocalciferol orally. The available liquid is labeled as 8000 units per 2 mL. We need to determine the volume in mL that provides 225,000 units.

Step-by-Step Solution:

1. Identify the given values:

• Ordered dose: 225,000 units
• Available concentration: 8000 units per 2 mL

2. Set up the conversion using dimensional analysis:

Volume required = 225,000 units × (2 mL / 8000 units)

• The units cancel out, leaving the result in mL.

3. Perform the calculation:

• Multiply: 225,000 × 2 = 450,000
• Divide: 450,000 ÷ 8000 = 56.25 mL

4. Rounding:

• Rounded to the nearest whole number, it is approximately 56 mL.

Final Answer:

• Nurse Smith should administer 56 mL of the ergocalciferol liquid.

ANSWER: 56 mL

Simplified recap: Multiply the ordered dose (225,000 units) by the conversion factor (2 mL/8000 units) to obtain 56.25 mL, which rounds to 56 mL.

EXPLANATION

✔Solution:

Understanding the Problem:

Nurse Lee must administer 15 mg of cortisone by mouth. The available tablets are 10 mg each. We need to calculate how many tablets provide the 15 mg dose.

Step-by-Step Solution:

1. Identify the given values:

• Ordered dose: 15 mg
• Tablet strength: 10 mg per tablet

2. Set up the conversion using dimensional analysis:

Number of tablets = 15 mg × (1 tablet / 10 mg)

• The "mg" units cancel out, leaving the result in tablets.

3. Perform the calculation:

• 15 ÷ 10 = 1.5 tablets

Final Answer:

• Nurse Lee should administer 1.5 tablets of cortisone.

ANSWER: 1.5 tablets

Simplified recap: Divide the ordered dose (15 mg) by the tablet strength (10 mg per tablet) to obtain 1.5 tablets.

EXPLANATION

✔Solution:

Understanding the Problem:

Nurse Reyes must administer 100 micrograms of levothyroxine by mouth. The available tablets are 0.05 mg each. To determine the number of tablets required, we first need to convert the tablet strength from milligrams to micrograms and then divide the ordered dose by the strength per tablet.

Step-by-Step Solution:

1. Convert the tablet strength to micrograms:

• 1 mg = 1000 micrograms
• 0.05 mg × 1000 = 50 micrograms per tablet

2. Calculate the number of tablets needed:

• Ordered dose = 100 micrograms
• Number of tablets = 100 micrograms ÷ 50 micrograms per tablet = 2 tablets

3. Final Answer:

• Nurse Reyes should administer 2 tablets of levothyroxine.

ANSWER: 2 tablets

Simplified recap: Each tablet contains 50 micrograms (0.05 mg). Dividing the ordered dose of 100 micrograms by 50 micrograms per tablet gives 2 tablets.

EXPLANATION

✔Solution:

Understanding the Problem:

Nurse Patel must administer ergocalciferol 225,000 units by mouth daily. The available tablets contain 50,000 units each. The task is to calculate how many tablets are needed to deliver 225,000 units.

Step-by-Step Calculation:

1. Identify the given values:

• Ordered dose: 225,000 units
• Tablet strength: 50,000 units per tablet

2. Set up the calculation using dimensional analysis:

Number of tablets = 225,000 units × (1 tablet / 50,000 units)

• The units cancel out, leaving the result in tablets.

3. Perform the calculation:

• 225,000 ÷ 50,000 = 4.5 tablets

4. Final Answer:

• Nurse Patel should administer 4.5 tablets of ergocalciferol.

ANSWER: 4.5 tablets

Simplified recap: Divide 225,000 units by 50,000 units per tablet to get 4.5 tablets.

EXPLANATION

✔Solution:

Understanding the Problem:

Nurse Cruz must administer 1.2 million units of penicillin via intramuscular injection. The available penicillin injection has a concentration of 500,000 units per mL. The task is to calculate the volume (in mL) needed to provide 1.2 million units.

Step-by-Step Solution:

1. Identify the given values:

• Ordered dose: 1,200,000 units
• Concentration: 500,000 units per 1 mL

2. Set up the conversion using dimensional analysis:

Volume required = 1,200,000 units × (1 mL / 500,000 units)

• The units "units" cancel out, leaving the result in mL.

3. Perform the calculation:

• 1,200,000 ÷ 500,000 = 2.4 mL

4. Final Answer:

• Nurse Cruz should prepare 2.4 mL of the penicillin injection.

ANSWER: 2.4 mL

Simplified recap: Divide the ordered dose (1,200,000 units) by the concentration (500,000 units/mL) to yield 2.4 mL.

EXPLANATION

✔Solution:

Understanding the Problem:

Nurse Smith must administer 40 mg of labetalol via IV push. The available vial has a concentration of 5 mg per mL. We need to calculate the volume in mL required to deliver 40 mg.

Step-by-Step Solution:

1. Identify the given values:

• Ordered dose: 40 mg labetalol
• Concentration: 5 mg per mL

2. Set up the conversion using dimensional analysis:

Volume required = 40 mg × (1 mL / 5 mg)

• The mg cancels out, leaving the result in mL.

3. Perform the calculation:

• 40 mg ÷ 5 mg/mL = 8 mL

4. Final Answer:

• Nurse Smith should prepare 8 mL for one dose.

ANSWER: 8 mL

Simplified recap: Divide the ordered dose (40 mg) by the concentration (5 mg/mL) to yield 8 mL.