RNC-NIC Pharmacology & Therapeutic Management 2 — Questions and Answers
Question 1: A neonate with persistent pulmonary hypertension (PPHN) is started on inhaled nitric oxide (iNO). Which parameter most directly indicates a therapeutic response?
- Increased mean airway pressure
- Improved oxygenation index (OI) (Correct answer)
- Decreased heart rate
- Increased FiO2 requirement
Correct answer: Improved oxygenation index (OI)
A decrease in the oxygenation index (OI = FiO2 × mean airway pressure × 100 / PaO2) indicates improved gas exchange and pulmonary vasodilation in response to iNO.
Question 2: A 28-week neonate requires caffeine citrate therapy. What is the recommended IV loading dose?
- 5 mg/kg
- 10 mg/kg
- 20 mg/kg (Correct answer)
- 40 mg/kg
Correct answer: 20 mg/kg
The standard caffeine citrate loading dose is 20 mg/kg IV, followed by a maintenance dose of 5–10 mg/kg/day.
Question 3: Which electrolyte abnormality is most commonly associated with prolonged furosemide therapy in neonates?
- Hyperkalemia
- Hypercalcemia
- Hypokalemia (Correct answer)
- Hypernatremia
Correct answer: Hypokalemia
Furosemide causes urinary wasting of potassium, sodium, and chloride, making hypokalemia the most common electrolyte imbalance with chronic use.
Question 4: A NICU nurse prepares to administer indomethacin to close a hemodynamically significant PDA. Which finding is an absolute contraindication?
- Platelet count of 90,000/mm³
- Serum creatinine of 1.2 mg/dL (Correct answer)
- Urine output of 0.8 mL/kg/hr
- Grade I IVH on head ultrasound
Correct answer: Serum creatinine of 1.2 mg/dL
Serum creatinine ≥1.8 mg/dL (or significant renal dysfunction) is a contraindication; a creatinine of 1.2 mg/dL warrants caution but is not an absolute cutoff—however, active renal impairment (oliguria <0.6 mL/kg/hr or elevated creatinine) contraindicates use.
Question 5: Vancomycin is prescribed for a neonate with culture-proven MRSA bacteremia. Which monitoring parameter is most important to guide dosing?
- Peak serum level
- Trough serum level
- AUC/MIC ratio (Correct answer)
- Urine vancomycin concentration
Correct answer: AUC/MIC ratio
Current guidelines recommend AUC/MIC-guided dosing (target AUC 400–600 mg·h/L) rather than trough-only monitoring to optimize efficacy and minimize nephrotoxicity.
Question 6: A term neonate with hypoxic-ischemic encephalopathy (HIE) is undergoing therapeutic hypothermia. Phenobarbital is ordered for seizures. How does hypothermia affect phenobarbital metabolism?
- Increases hepatic clearance, requiring higher doses
- Decreases hepatic clearance, increasing drug levels (Correct answer)
- No significant effect on drug metabolism
- Increases renal excretion, requiring more frequent dosing
Correct answer: Decreases hepatic clearance, increasing drug levels
Therapeutic hypothermia reduces hepatic enzyme activity and drug clearance, leading to higher phenobarbital levels and potential toxicity at standard doses.
Question 7: A nurse is administering a continuous morphine infusion to a ventilated preterm neonate. Which adverse effect requires immediate intervention?
- Heart rate of 150 bpm
- Blood pressure of 48/26 mmHg (Correct answer)
- SpO2 of 97%
- Urine output of 2 mL/kg/hr
Correct answer: Blood pressure of 48/26 mmHg
Morphine causes histamine release and vasodilation, which can lead to hypotension; a low BP in a preterm neonate on morphine infusion requires prompt assessment and possible dose reduction or fluid bolus.
RNC-NIC Pharmacology & Therapeutic Management 2
A neonate with persistent pulmonary hypertension (PPHN) is started on inhaled nitric oxide (iNO).
Which parameter most directly indicates a therapeutic response?