CRNI Exam Neonatal Infusion Therapy — Questions and Answers
Question 1: An umbilical arterial catheter (UAC) is placed in a neonate. Which position is considered the 'high' position and is preferred to avoid renal and mesenteric artery occlusion?
- T6–T9 (above the diaphragm) (Correct answer)
- L3–L4 (lumbar region)
- T10–T12 (just above the renal arteries)
- Below L5 (pelvic region)
Correct answer: T6–T9 (above the diaphragm)
The 'high' UAC position (T6–T9, above the diaphragm but below the ductus arteriosus) is preferred because it avoids the origin of the celiac, superior mesenteric, and renal arteries, thereby reducing the risk of thromboembolism to those vessels compared to a 'low' position at L3–L4.
Question 2: When calculating intravenous fluid requirements for a premature neonate at 26 weeks gestation in the first 24 hours of life, which factor most significantly increases insensible water loss compared to a term neonate?
- Higher glomerular filtration rate
- Greater skin surface area relative to body weight and immature skin barrier (Correct answer)
- Increased renal sodium reabsorption
- Lower respiratory rate
Correct answer: Greater skin surface area relative to body weight and immature skin barrier
Extremely premature neonates have a markedly high ratio of skin surface area to body weight and a very thin, poorly keratinized skin barrier, leading to dramatically increased transepidermal water loss (TEWL). This can require fluid intakes of 100–200 mL/kg/day in the first days of life under radiant warmers.
Question 3: Which glucose infusion rate (GIR) range is generally targeted to maintain euglycemia in a term neonate receiving parenteral nutrition in the first few days of life?
- 1–2 mg/kg/min
- 4–8 mg/kg/min (Correct answer)
- 12–15 mg/kg/min
- 18–20 mg/kg/min
Correct answer: 4–8 mg/kg/min
A GIR of 4–8 mg/kg/min approximates the hepatic glucose production rate in term neonates and is used as the starting target to maintain blood glucose between 50–120 mg/dL. Rates above 12–15 mg/kg/min increase the risk of hyperglycemia and fatty liver.
Question 4: A peripherally inserted central catheter (PICC) is placed in a neonate. The tip is confirmed by X-ray to be in the right atrium. What is the appropriate nursing action?
- Begin infusion immediately because the right atrium is an acceptable PICC tip location in neonates
- Notify the provider to reposition the catheter to the lower one-third of the superior vena cava (Correct answer)
- Advance the catheter 2 cm further to reach the inferior vena cava
- Withdraw the catheter to the subclavian vein and restart infusion
Correct answer: Notify the provider to reposition the catheter to the lower one-third of the superior vena cava
PICC tip placement in the right atrium is not acceptable because it increases the risk of cardiac arrhythmias and cardiac tamponade. The correct tip position for a neonatal upper-extremity PICC is the lower one-third of the SVC at the cavoatrial junction. The provider should be notified for repositioning before use.
Question 5: Neonates are at higher risk for hypocalcemia during blood transfusion with citrate-containing blood products compared with adults. What is the primary physiological reason?
- Neonates have higher ionized calcium levels at baseline
- Neonatal livers have immature capacity to metabolize citrate, allowing it to chelate ionized calcium (Correct answer)
- Neonates receive larger volumes of blood relative to their weight
- Neonatal kidneys excrete calcium more rapidly during transfusion
Correct answer: Neonatal livers have immature capacity to metabolize citrate, allowing it to chelate ionized calcium
Citrate is the anticoagulant used in stored blood products; it is normally metabolized rapidly by the liver. Neonates—especially premature infants—have immature hepatic citrate metabolism, so citrate accumulates and chelates free ionized calcium, causing hypocalcemia, which can lead to cardiac dysfunction.
Question 6: When administering a continuous IV medication infusion to a 28-week premature neonate, which infusion pump feature is MOST critical for patient safety given the extremely small volumes involved?
- Wireless connectivity for remote reprogramming
- Anti-free-flow clamp
- Syringe pump with accurate low-flow delivery (≤1 mL/hr) and anti-siphon valve (Correct answer)
- Large-volume reservoir capacity
Correct answer: Syringe pump with accurate low-flow delivery (≤1 mL/hr) and anti-siphon valve
Neonatal infusions often run at rates of 0.1–1 mL/hr. Standard volumetric pumps are inaccurate at these flows. Syringe pumps specifically designed for neonates provide accurate delivery at very low rates and incorporate anti-siphon valves to prevent unintended bolus delivery when the syringe is raised above the patient—a potentially fatal error in tiny neonates.
CRNI Exam Neonatal Infusion Therapy
An umbilical arterial catheter (UAC) is placed in a neonate.
Which position is considered the 'high' position and is preferred to avoid renal and mesenteric artery occlusion?