RNC-NIC Pharmacology & Therapeutic Management 5

Question 1

A term neonate is receiving heparin through a PICC line for catheter patency. Which laboratory value most directly reflects heparin anticoagulation effect?

Accepted Answer

Anti-factor Xa level

Answer

Anti-factor Xa levels are the most reliable measure of heparin anticoagulation in neonates because aPTT is affected by the physiological coagulation differences in newborns.

Question 2

A neonate with persistent hypoglycemia unresponsive to glucose infusion rates >12 mg/kg/min is started on diazoxide. What is the mechanism of action of diazoxide in neonatal hypoglycemia?

Accepted Answer

Opens ATP-sensitive potassium channels, suppressing insulin release

Answer

Diazoxide opens ATP-sensitive K+ channels on pancreatic beta cells, hyperpolarizing the membrane and inhibiting insulin secretion—useful in hyperinsulinemic hypoglycemia.

Question 3

A preterm neonate develops necrotizing enterocolitis and is placed on bowel rest with IV antibiotics. After 14 days of NPO status, which nutritional supplementation becomes critically important to prevent deficiency?

Accepted Answer

Trace element and vitamin supplementation via TPN

Answer

Prolonged NPO with TPN requires complete trace elements and vitamins to be added to the TPN solution to prevent deficiency states that would otherwise be supplied by enteral feeds.

Question 4

A neonate with meningitis is receiving ampicillin and cefotaxime. CSF culture returns group B Streptococcus sensitive to penicillin. What is the recommended duration of antibiotic therapy?

Accepted Answer

21 days

Answer

GBS meningitis in neonates requires a minimum of 14–21 days of IV penicillin therapy; most guidelines recommend 21 days due to the risk of relapse and neurological sequelae.

Question 5

A nurse is preparing to administer sildenafil to a neonate with PPHN. What is the primary mechanism by which sildenafil improves pulmonary hypertension?

Accepted Answer

Inhibits phosphodiesterase-5, increasing cGMP and promoting vasodilation

Answer

Sildenafil inhibits PDE-5, the enzyme that degrades cGMP; elevated cGMP causes pulmonary vascular smooth muscle relaxation and reduces pulmonary vascular resistance.

(RNC-NIC) Registered Nurse Certified in Neonatal Intensive Care Practice Test

(RNC-NIC) Registered Nurse Certified in Neonatal Intensive Care Practice Test

RNC-NIC Pharmacology & Therapeutic Management 5