Question

During life in utero oxygenation of the fetus occurs through transplacental gas exchange. When birth occurs, four factors combine to stimulate the respiratory center in the medulla. The initiation of respiration then follows. Which is NOT one of these essential factors?

a. Chemical
b. Mechanical
c. Thermal
d. Psychologic

Answer 1

The d. psychologic factor is NOT one of the essential factors that stimulate the respiratory center at birth. The essential factors include chemical, mechanical, and thermal stimuli.

Step-by-step explanation:

When birth occurs, stimulation of the respiratory center in the medulla is essential for initiating respiration in a newborn. The question revolves around identifying which factor is NOT included in the four essential factors that combine to stimulate the respiratory center at birth. The factors that play a role include chemical, mechanical, and thermal stimuli. The psychologic factor is not one of those essential factors that contribute to the stimulation of respiration at birth.

Chemical stimuli involve changes in the blood levels of oxygen and carbon dioxide due to labor contractions; mechanical stimuli arise from the compression and expansion of the chest during and after delivery; and thermal stimuli are from the shift from the warm environment of the uterus to the cooler external environment. Together, these factors stimulate the newborn to take the first breath.