Neonatal Nurse Practitioner Practice Exam

What is the primary action of methylxanthines in neonates receiving therapy for apnea?

1. Decrease hypoxemia through improved pulmonary function

2. Act by stimulation of central respiratory chemoreceptors

3. Increase cerebral blood flow velocity

4. Enhance oxygenation of blood

The correct answer is: Act by stimulation of central respiratory chemoreceptors

Methylxanthines, such as caffeine, primarily act by stimulating central respiratory chemoreceptors in neonates who are experiencing apnea. This stimulation enhances the drive to breathe, which is crucial for infants, particularly premature ones, who may have immature respiratory systems. By increasing the sensitivity of the respiratory centers in the brain, methylxanthines help to promote more regular breathing patterns, thereby reducing the frequency and severity of apnea episodes. While improving pulmonary function and enhancing oxygenation of the blood are important in the overall management of apnea, those actions are secondary effects resulting from more stable and consistent breathing patterns initiated by the central stimulation. Increasing cerebral blood flow velocity can occur as a response to improved oxygenation and decreased apneic events, but it is not the primary mechanism by which methylxanthines exert their therapeutic benefit in this context.