ADN 109 Dosage Calculations Exam Questions and Answers
1. The healthcare provider prescribes a continuous infusion of 5% dextrose in 0.45% sodium
... [Show More] chloride at 85 ml/hour. The IV administration set delivers 10 gtt/ml. The nurse should regulate the drop rate to deliver how many gtts/minute? (Enter numeric value only. If rounding is required, round to the nearest whole number.)
Answer: Volume/Time (minutes) x drop factor (gtt/ml) = 85 ml/ 60 minutes x 10 gtt/ml = 14.16 =
14 gtt/minute
2. A client receives a prescription for tobramycin sulfate (Nebcin) 0.128 grams IV q8 hours. Tobramycin is available in liquid concentration of 40 mg/ml. How many ml should the practical nurse administer? (Enter numeric value only. If rounding is required, round to the nearest tenth.)
Answer : First using the known conversion:
1 gram = 1000 mg = 0.128 gram = 128 mg Next use the Desired/Have x 1 ml =
128 mg/40 mg x 1ml = 3.2 ml
3. A client returning from surgery has a prescription for an IV of 09% sodium chloride to be infused at 250 ml over 3 hours. The nurse should program the infusion pump to deliver how many ml/hour? (Enter numeric value only. If rounding is required, round to the nearest whole number.)
Answer: 250 ml :3 hours X 1 hour 250/X :3/1
250: 3X
X=83 ml/hour
4. A client scheduled for surgery is to receive an IV infusion of 0.9% sodium chloride with prochlorperazine edisylate (Compazine) 10 mg/50 ml over 30 minutes. The nurse should program the infusion pump to deliver how many ml/hour? (Enter numeric value only.)
Answer: Calculate: 50 ml : 30 minutes :: X ml : 60 minutes 50/X :: 30/60 3000 = 15X X = 100 ml
5. The healthcare provider prescribes a continuous infusion of dextrose 5% in water with isoproterenol (Isuprel) 2 mg in 500 ml at a rate of 5 mcg/minute for a client with cardiac arrhythmia. The nurse should program the infusion pump to deliver how many ml/hour? (Enter numeric value only. If rounding is required, round to the nearest hundredth.)
Answer: First using the known conversion 1 mg = 1000 micrograms.
Next, calculate the number of micrograms in solution: 1mg = 1000 mcg :: 2 mg = 2000 mcg
Then calculate how many ml of solution contain 5 mcg dose/minute: 2000 mcg : 500ml :: 5 mcg : X ml
2000/5 :: 500/X
X = 1.25 ml/minute
Calculating ml/hour: 1.25 ml x 60 minutes = 75 ml/hour
6. The nurse plans to administer labetalol hydrochloride (Trandate) 0.3 grams PO to a client with hypertension. Trandate is available in 200 mg scored tablets. How many tablets should the nurse administer? (Enter numeric value only.)
Answer: First convert grams to milligrams using the known conversion: 1 gram = 1000 mg.
0.1 gram = 100 mg as 0.3 gram = 300 mg
Next using the formula, Desired/Available x 1 tablet = 300 mg/200 mg x 1 = 1.5 tablets
7. A client with multiple sclerosis is prescribed Dantrolene (Dantrium) 0.1 grams PO bid for spasticity. Dantrolene is available in 100 mg capsules. How many capsules should the practical nurse administer? (Enter numeric value only.)
Answer: Using the conversion of 1 gram = 1000 mg:
0.1 gram = 100 mg 100 mg = 1 capsule
8. A 49-year-old client with myasthenia gravis is receiving pyridostigmine (Mestinon) 126 mg PO every 4 hours. The available form is 60 mg in 5 ml syrup. How many ml should the practical nurse administer? (If rounding is required, round to the nearest tenth.) Rationale
Answer: Using the formula, Desired dose / dose on Hand x Quantity of volume on hand (D/H x Q):
126 mg / 60 mg x 5 ml = 10.5 ml
9. Mineral oil U.S.P 30 ml PO daily for 3 days is prescribed for a client who is experiencing severe constipation. The medication dose cup is marked in tablespoons. How many tablespoons should the practical nurse administer? (Enter numeric value only.)
Answer: 15 ml equals 1 Tablespoon.
Use the ratio equation: 15 ml : 1 Tbs :: 30 ml : X 15 / 30 :: 1 / X
15X = 30
X = 2 Tablespoons
10. A client with Mycobacterium avium complex (MAC) is receiving an infusion of 5 % dextrose in water with amikacin (Amikin) 0.572 grams/100 ml every 12 hours. The practical nurse prepares the dose of amikacin using a vial labeled, " 250 mg/ml." How many ml should the practical nurse add to the infusion? (Enter numeric value only. If rounding is required, round to the nearest tenth.)
Answer:
First convert gram to milligram:
1 gm = 1000mg .572 gram x 1000 = 572 mg Next use the formula D/H x Q:
572/250 x 1 = 2.288 (rounded to) 2.3 ml
11. A client who has a gastrostomy feeding tube is receiving 3/4 strength Ensure 240 ml every 6 hours. Full strength Ensure is available in a 240 ml can. The nurse should use how many ml of Ensure to prepare the feeding? (Enter numeric value only. If needed, round to the nearest whole number.)
Answer: 240 ml Ensure : 1 :: X ml Ensure : 0.75 240/X : 1 / 0.75 X = 240 x 0.75 = 180 ml Ensure + 60 ml water = 240 ml
180 of ensure ONLY
12. A client returns to the nursing unit from surgery with a prescription for Lactated Ringer's solution 1,000 ml to be infused over 10 hours. The IV administration set delivers 60 gtts/ml. The nurse should regulate the infusion to deliver how many gtts/minute?
Answer: First convert hours to minutes: 10 hrs x 60 = 600 minutes. Using the formula Volume/Time x drop factor: 1000 ml /600 minutes = 1.66666 x 60 = 100 gtts minute.
13. A client receives a prescription for an intravenous infusion 0.45% sodium chloride 500 ml to be infused over 6 hours. The nurse should program the infusion pump to deliver how many ml/hour? (Enter numeric value only. If rounding is required, round to the nearest whole number.)
Answer: Calculate using Volume/Time: 500 ml/6 hours = 83.3 ml/hour = 83
14. The healthcare provider prescribes a continuous intravenous infusions of dextrose 5% and 0.45% sodium chloride with KCI 20 mEq/1000 ml to be delivered over 8 hours. The practical nurse should program the infusion pump to deliver how many ml/hour? (Enter numeric value only. If rounded is required round to the nearest whole number.)
Answer: Using the formula volume/ time : 1000ml/8 hours = 125 ml/hour
15. A child with a urinary tract infection is receiving Cephalexin (Keflex) 100 mg suspension PO QUID. Keflex oral suspension is labeled “125 mg in 5 ml “. How many ml should the practical nurse administer? (Enter numeric value only. If rounding is required, round to the nearest tenth.)
Answer: Using the formula Desired/ Have available x Quantity: 100/125 x 5 – 500/125 = 4 ml
16. A client who has heart failure with paroxysmal atrial tachycardia is receiving digoxin (Lanoxin) 0.45 mg IV as the initial digitalizing dose. The pharmacy provides 0.25 mg/ ml. How many ml should the practical nurse administer? (Enter numeric value only. If rounding is required, round to the nearest tenth.)
Answer: Using the formular D/H x Q: 0.46mg/0.25mg x 1 mL = 1.8 mL
17. A client with impetigo receives a prescription for azithromycin (Zithromax) 500 mgPO on day 1, then 250 mg/day on days 2 through 5 for a total administration of 1.5 gram. The pharmacy has 250 mg tablets available.
Answer: Using Desired/Have available formula : 500mg/250mg x 1 times a day = 2 tablets a Day
1. Days 2 to 5: 1 tablet each day = 4 tablets. 2 + 4 = 6
18. A client receives a prescription for levothyroxine sodium (Synthroid) 0.05 mg by mouth once daily. The medication is available in scored tablets labeled 0.1 mg. How many tablets should thenurse administer? (If rounding is required, round to the nearest tenth.)
Answer: Using the formula. Desired/ Available x 1 tablet = 0.05/0.1 x 1 = 0.5
19. The nurse needs to calculate a client's oral temperature of 99.2??? Fahrenheit to Celsius. What temperature in Celsius should the nurse document? (Enter numeric value only. Round to the nearest tenth.
Answer: Use the formula to convert Fahrenheit to Celsius ( C), Fahrenheit temperature ( 99.2) minus 32 divided by 1.8 = 39.3 degrees C.
20. A child who weighs 55 pounds receives a prescription for atovaquone with proguanil (Malarone Pediatric) 125 mg/50 mg PO daily. A drug reference states that children 11 to 20 kg should receive 1 pediatric tablet daily; 21 to 30 kg should receive 2 pediatric tablets daily; 31 to 40 kg should receive 3 pediatric tablets daily; and greater than 40 kg should receive 1 adult tablet daily with food. The drug is available as atovaquone 62.5 mg/proguanil 25 mg pediatric tablets. How many tablets should the nurse administer?
Answer: Calculate each drug component dose, using the formula, D/H 125mg/ 62.5 mg
( atovaquone) = 2 combined with 50 mg/ 25 mg (proguanil) = 2 The child should receive 2 tablets. [Show Less]