Low Risk Neonatal Nurse Exam Low Risk Neonatal Nurse Exam Thermoregulation & Neonatal Environment 2 — Questions and Answers
Question 1: What is the primary physiologic mechanism newborns use to generate heat when cold-stressed?
- Shivering thermogenesis
- Non-shivering thermogenesis via brown adipose tissue metabolism (Correct answer)
- Increased voluntary muscle activity
- Peripheral vasodilation
Correct answer: Non-shivering thermogenesis via brown adipose tissue metabolism
Newborns generate heat primarily through non-shivering thermogenesis by metabolizing brown adipose tissue (BAT), located around the neck, scapulae, and adrenal glands.
Question 2: Kangaroo Mother Care (KMC) is effective for thermoregulation primarily because it provides which type of heat transfer?
- Radiation from overhead warming lights
- Conduction from direct skin-to-skin contact with the parent's chest (Correct answer)
- Convection from warmed air currents
- Evaporation from moisture on the infant's skin
Correct answer: Conduction from direct skin-to-skin contact with the parent's chest
KMC transfers heat by conduction through direct skin-to-skin contact, stabilizing the newborn's temperature effectively.
Question 3: Which newborn is at greatest risk for impaired thermoregulation?
- Term infant born at 40 weeks with birth weight of 3.5 kg
- Late preterm infant born at 35 weeks with birth weight of 2.1 kg (Correct answer)
- Term infant born by cesarean to a healthy mother
- Post-term infant born at 41 weeks with intact vernix
Correct answer: Late preterm infant born at 35 weeks with birth weight of 2.1 kg
Late preterm infants have less brown fat, thinner skin, and less subcutaneous fat than term infants, placing them at highest risk for thermoregulation problems.
Question 4: A newborn is placed under a radiant warmer after birth. What is the correct servo-control mode setting for skin temperature?
- 36.0–36.5°C (96.8–97.7°F) (Correct answer)
- 37.5–38.0°C (99.5–100.4°F)
- 35.0–35.5°C (95.0–95.9°F)
- 38.5–39.0°C (101.3–102.2°F)
Correct answer: 36.0–36.5°C (96.8–97.7°F)
In servo-control mode, the skin temperature probe target is set to 36.0–36.5°C to maintain a neutral thermal environment.
Question 5: Cold stress in a newborn most directly leads to which metabolic consequence?
- Hyperkalemia
- Hypoglycemia due to increased glucose consumption for thermogenesis (Correct answer)
- Metabolic alkalosis
- Elevated serum calcium
Correct answer: Hypoglycemia due to increased glucose consumption for thermogenesis
Cold stress increases metabolic rate and glucose consumption during BAT thermogenesis, rapidly depleting neonatal glycogen stores and causing hypoglycemia.
Question 6: Which environmental modification best reduces convective heat loss in the newborn nursery?
- Placing the crib near a window for natural light
- Ensuring air vents do not blow directly on the newborn's crib (Correct answer)
- Keeping room humidity at 20%
- Using a thin single blanket only
Correct answer: Ensuring air vents do not blow directly on the newborn's crib
Directing air vents away from the newborn prevents convective heat loss caused by air movement over the infant's body surface.
Low Risk Neonatal Nurse Exam Low Risk Neonatal Nurse Exam Thermoregulation & Neonatal Environment 2
What is the primary physiologic mechanism newborns use to generate heat when cold-stressed?