NCLEX: Drug Dosage Calculation Exam 4

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Exam Mode – Questions and choices are randomly arranged, time limit of 1min per question, answers and grade will be revealed after finishing the exam.

Text Mode – Text version of the exam

1. The recommended IV dose of gentamicin is 1 to 5 mg/kg. What is a safe range to administer to an adult man weighing 190 pounds?

1. 1 mg to 5 mg
2. 50 mg to 250 mg
3. 86 mg to 431 mg
4. 432 mg to 500 mg

2. You are caring for a patient at home who must take magnesium hydroxide/aluminum hydroxide (Maalox) 30 mL PO. How will you instruct the patient to measure the dose using ordinary household measuring devices?

1. 1 tbsp
2. 1 1/2 tbsp
3. 2 tbsp
4. 3 tbsp

3. You have an order to administer 1 L of 5% Dextrose in 0.45 normal saline IV over 16 hours. How many milliliters per hour will you set on the IV infusion controller?

1. 63 mL/hour
2. 60 mL/hour
3. 55 mL/hour
4. 38 mL/hour

4. You have an order to administer 1 L of D5W IV over 8 hours. How many drops per minute will you set if you are using tubing with a drop factor of 15?

1. 2 gtts/min
2. 31 gtts/min
3. 63 gtts/min
4. 125 gtts/min

5. Your order reads gatifloxacin (Tequin) 400 mg IV daily. It arrives in 50 mL of D5W, to run over 30 minutes. How many drops per minute will you set if you have tubing with a drop factor of 10?

1. 17 gtts/min
2. 13 gtts/min
3. 10 gtts/min
4. 8 gtts/min

6. You have an order to administer heparin sodium IV at 1000 units per hour. It is supplied by your pharmacy as 25,000 units in 250 mL of D5W. For how many milliliters per hour should you program the controller?

1. 10 mL/hour
2. 15 mL/hour
3. 20 mL/hour
4. 25 mL/hour

7. Your patient has an order for heparin SC 2500 units bid. You have on hand heparin 5000 units/mL. How many milliliters will you administer ?

1. 0.5 mL
2. 1 mL
3. 2 mL
4. 4 mL

8. You evaluate a patient’s intake and output for 8 hours. Intake for 8 hours:

• 3 8-oz cups of coffee
• 4 oz orange juice
• 3/4 cup of milk
• 8 oz tomato soup
• 1/2 cup Jello
• 2 cups of water
• 750 mL of 0.9% normal saline IV

How many milliliters should you record as intake?

1. 2,061 mL intake
2. 2,160 mL intake
3. 2,601 mL intake
4. 2,610 mL intake

9. The physician orders codeine gr 1/4IM every 4 hours prn for a patient with pain. You have on hand codeine gr 1/2 per mL. What is the correct dose?

1. 0.5 mL
2. 1 mL
3. 2 mL
4. 3 mL

10. A patient is receiving 250,000 units of penicillin G IM every 6 hours. You have on hand 300,000 units/mL. How much will you draw into the syringe?

1. 2 mL
2. 1.2 mL
3. 1 mL
4. 0.8 mL

Answers and Rationales

1. Answer: C.
   • (1 mg/1 kg) x 190lbs x (1 kg/ 2.2 lbs.) = 86 mg
   • (5 mg/ 1 kg) x 190 lbs x (1 kg/2.2 lbs.) = 431 mg
   • *The safe range is between 86 to 431 mg.
2. Answer: C. 30 mL x (1 tbsp/15 mL) = 2 tbsp
3. Answer: A. (1 L/16 hrs.) x (1,000 mL/1 L) =63 mL/hour. 
4. Answer: B. (1 L/8hrs) x (1,000mL/1L) x (1 hr/60 mins) x (15 gtts/mL) =31 gtts/min
5. Answer: A. (50 mL/ 30mins) x (10 gtts/mL)=  17 gtts/min
6. Answer: A. (1,000 units/ hour) x (250 mL/ 25,000 units)= 10 mL/hour
7. Answer: A. 2,500 units x (1 mL/5,000 units) =  0.5 mL
8. Answer: D. 
   • *First, you must convert all amounts to the same units, usually milliliters.
     • 3 cups x (8 oz/ 1 cup) x (30 mL/1 oz)= 720 mL coffee
     • 4 oz x (30 mL/1 oz)= 120 mL orange juice
     • 3/4 cup x (240 mL/1 cup) = 180 mL milk
     • 8 oz x (30 mL/1 oz)= 240 mL soup
     • 1/2 cup x (240mL/1 cup) = 120 mL Jello
     • 2 cups x  (240 mL/1 cup)= 480 mL water
   • Now add: 720 + 120 + 180 + 240 + 120 + 480 + 750 = 2,610 mL intake
9. Answer: A. 1/4 gr x [1mL/(1/2 gr)] = 0.5 mL
10. Answer: D. 250,000 units x (1 mL/300,000 units)= 0.8 mL