RNC-NIC Thermoregulation 2 — Questions and Answers
Question 1: A 28-week preterm infant is in an incubator set to servo-control mode. The abdominal skin temperature reads 36.0°C. What is the most appropriate nursing action?
- Increase the incubator air temperature manually
- Check probe placement and ensure good skin contact (Correct answer)
- Switch to manual air-temperature mode immediately
- Obtain a rectal temperature to confirm hypothermia
Correct answer: Check probe placement and ensure good skin contact
A falsely low skin temperature reading is most often caused by a displaced or poorly adhered servo-control probe, so verifying probe placement is the first step.
Question 2: Which mechanism of heat loss is most significant when a newborn is placed on a cold scale without a cover?
- Evaporation
- Radiation
- Convection
- Conduction (Correct answer)
Correct answer: Conduction
Direct contact between the infant's skin and a cool surface transfers heat by conduction.
Question 3: A term neonate born via cesarean section is brought to the warmer. The nurse notes the infant is wet with amniotic fluid. Which intervention should be performed FIRST?
- Apply a hat to the head
- Place the infant under the radiant warmer
- Thoroughly dry the infant and remove wet linens (Correct answer)
- Obtain an axillary temperature
Correct answer: Thoroughly dry the infant and remove wet linens
Drying the infant and removing wet linens immediately reduces evaporative heat loss, which is the primary cause of heat loss in a wet newborn.
Question 4: Brown adipose tissue (BAT) thermogenesis in neonates is stimulated primarily by which mechanism?
- Shivering triggered by anterior hypothalamus signals
- Norepinephrine release activating uncoupling protein-1 in mitochondria (Correct answer)
- Glucagon-induced glycogenolysis in muscle tissue
- Cortisol release from the adrenal cortex
Correct answer: Norepinephrine release activating uncoupling protein-1 in mitochondria
Cold stress triggers norepinephrine release, which activates uncoupling protein-1 (thermogenin) in BAT mitochondria, generating heat through non-shivering thermogenesis.
Question 5: A nurse is caring for a 32-week infant and notices peripheral vasoconstriction, acrocyanosis, and a widening core-to-peripheral temperature gradient. These findings are MOST consistent with:
- Hyperthermia
- Cold stress (Correct answer)
- Sepsis-induced vasodilation
- Polycythemia
Correct answer: Cold stress
Peripheral vasoconstriction and an increasing core-to-peripheral temperature gradient are early compensatory responses to cold stress in neonates.
Question 6: What is the primary rationale for placing a polyethylene bag over an extremely premature infant (< 28 weeks) immediately at delivery?
- To reduce convective heat loss from air currents
- To decrease evaporative heat loss through the immature skin (Correct answer)
- To provide a sterile barrier against infection
- To facilitate kangaroo mother care in the delivery room
Correct answer: To decrease evaporative heat loss through the immature skin
Extremely premature skin is highly permeable, and a polyethylene wrap prevents evaporative water and heat loss without requiring drying.
Question 7: A term infant undergoing therapeutic hypothermia for hypoxic-ischemic encephalopathy should be maintained at which target core temperature?
- 32.0–33.0°C
- 33.5–34.5°C (Correct answer)
- 34.0–35.0°C
- 35.5–36.5°C
Correct answer: 33.5–34.5°C
Evidence-based therapeutic hypothermia protocols target a core temperature of 33.5°C (±0.5°C) for 72 hours to provide neuroprotection.
RNC-NIC Thermoregulation 2
A 28-week preterm infant is in an incubator set to servo-control mode.
The abdominal skin temperature reads 36.0°C.
What is the most appropriate nursing action?