Saudi Prometric Nursing Pharmacology and Drug Calculations 2 — Questions and Answers
Question 1: A nurse is administering IV potassium chloride (KCl) to correct hypokalemia. What is the maximum safe rate for IV KCl administration in a peripheral line?
- 10 mEq/hour (Correct answer)
- 40 mEq/hour
- 20 mEq/hour
- 5 mEq/hour
Correct answer: 10 mEq/hour
The maximum safe rate for peripheral IV KCl administration is 10 mEq/hour in a concentration of no more than 40 mEq/L. Faster rates can cause cardiac arrhythmias. Central line administration allows higher rates with continuous cardiac monitoring.
Question 2: A patient weighing 60 kg is prescribed IV aminophylline at a maintenance dose of 0.5 mg/kg/hr. The available solution is 250 mg in 250 mL. What is the infusion rate in mL/hr?
- 30 mL/hr (Correct answer)
- 15 mL/hr
- 60 mL/hr
- 12 mL/hr
Correct answer: 30 mL/hr
Dose per hour = 0.5 mg/kg/hr × 60 kg = 30 mg/hr. Concentration = 250 mg/250 mL = 1 mg/mL. Rate = 30 mg/hr ÷ 1 mg/mL = 30 mL/hr.
Question 3: A patient is prescribed warfarin. Which medication interaction significantly increases the risk of bleeding?
- Aspirin and NSAIDs (Correct answer)
- Vitamin K supplements
- Cholestyramine
- Omeprazole
Correct answer: Aspirin and NSAIDs
Aspirin and NSAIDs inhibit platelet aggregation and can also inhibit warfarin metabolism, significantly increasing anticoagulant effect and bleeding risk. The combination of warfarin anticoagulation plus antiplatelet effect is particularly dangerous for GI bleeding.
Question 4: The nurse is monitoring a patient receiving IV vancomycin. Which adverse effect requires serum drug level monitoring?
- Nephrotoxicity and ototoxicity (Correct answer)
- Hepatotoxicity and cholestasis
- Bone marrow suppression
- Peripheral neuropathy
Correct answer: Nephrotoxicity and ototoxicity
Vancomycin can cause nephrotoxicity (renal damage) and ototoxicity (hearing loss) at elevated serum levels. Trough levels are monitored to ensure therapeutic efficacy while preventing toxicity. AUC/MIC-guided dosing is the current standard.
Question 5: A nurse is preparing oral medications. The prescription reads: 'amoxicillin 750 mg PO. Available: 250 mg/5 mL suspension.' How many mL should be administered?
- 15 mL (Correct answer)
- 7.5 mL
- 5 mL
- 10 mL
Correct answer: 15 mL
Volume = (desired dose / available dose) × volume = (750 mg / 250 mg) × 5 mL = 3 × 5 = 15 mL. This is a standard oral liquid calculation.
Question 6: A patient is prescribed digoxin 0.125 mg PO daily. The nurse checks the apical pulse and counts 54 beats per minute. What is the correct action?
- Hold the dose and notify the physician — pulse below 60 bpm (Correct answer)
- Administer the dose as prescribed — slight bradycardia is expected
- Administer half the dose and reassess in 1 hour
- Increase the dose to achieve a target HR of 60 bpm
Correct answer: Hold the dose and notify the physician — pulse below 60 bpm
Digoxin should be withheld when the apical pulse is below 60 beats per minute (bradycardia), as this may indicate digoxin toxicity. The prescribing physician should be notified and the order reassessed before administration.
Saudi Prometric Nursing Pharmacology and Drug Calculations 2
A nurse is administering IV potassium chloride (KCl) to correct hypokalemia.
What is the maximum safe rate for IV KCl administration in a peripheral line?