A pregnant woman at 25 weeks of gestation visits the prenatal clinic for a checkup. She asks the nurse how the baby is able to breathe on his own following childbirth

Question

The nurse plans to explain the factors that influence the initiation of the newborn's first breath, including which of the following?
A.
A quiet environment
B.
Drastic change in temperature
C.
Hypoxia
D.
Initiation of breastfeeding
E.
Recoil of the chest wall after delivery of the trunk

Answer 1

ANS: B, C, E
Hypoxia causes blood oxygen levels (PO2) and pH to drop. Subsequently, blood carbon dioxide levels (PCO2) begin to rise and prompt the respiratory center within the medulla to initiate breathing. Once the fetus moves from the intrauterine to the extrauterine environment, the drastic change in temperature helps to stimulate the initiation of respirations, because sensors in the skin respond to the temperature changes and send signals to the respiratory system in the brain. Recoil of the chest wall after delivery of the neonate's trunk creates a negative intrathoracic pressure, which facilitates a small, passive inspiration of air. An extremely sensory-overloaded environment filled with a multitude of tactile, visual, and auditory stimuli aids in the initiation of respirations.
A quiet environment and breastfeeding do not assist in the initiation of independent respiratory function.