SUMMARY OF VENTILATORY RESPONSES TO LARYNGEAL AFFERENTS
Apnea and breathing inhibition in animals and humans are normally caused by laryngeal mucosa. The type of apnea, in this case, is often reflex-induced. In many cases, reflex-apnea is characterized by contracting thyroarytenoid muscles that in turn lead to the closure of glottis as well as swallowing movement. Such closure signifies the active stimulation of brainstem centers that are related to the expiratory system. Reflex-induced apnea undergoes maturational changes as evident in the preterm infants and older piglets. In the case of infants, there is an exhibition of prolonged apnea compared to the older one. Laryngeal and apnea adduction that occurs during laryngeal stimulation is often purposed to offer protection of lungs from aspirations. It leads to the sensitivity of the lungs and the main respiratory system. Also, maturational changes can lead to postnatal changes in the reflex system. Apneic infants exhibit the physiological characteristics inhibited by the chemoreceptor functions near the ventral medullary surface.
Implications for management
Apnea is caused by an immature respiratory system but can as well be caused by certain diseases affecting the preterm infants. There is a necessity to find the causes thoroughly when the frequency of bradycardia abnormally increases.
Xanthine
Methylxanthines have often been adopted for the treatment of infant apnea for more than thirty years. In the case, caffeine and theophylline have been used. Xanthine therapy normally helps improve the ventilation thus increases the sensitivity to CO2. It also decreases hypoxic depression thereby enhancing the diaphragmatic activity.
The therapy helps decrease laryngeal obstruction by splitting the upper airway that has positive pressure. Certain equivalent treatments have been recommended to enable the delivery of CPAP. One such therapy is high-flow nasal cannula.
Other approaches
Skin-to-skin nursing, as well as Kangaroo nursing, can be used to stabilize the infants with the suggestion that it decreases the rates of apnea. Despite, their wide acceptance, their effectiveness has not been supported by data.
Relevance to outcome
Immature infants experience apnea of prematurity for longer than normal 36-40 weeks of postconceptional age. There is clarity in the absence of a relationship between SIDS and apnea of prematurity. The two remain linked, but there is no clarity. Also, there is no connection between apnea and breathing abnormalities experienced by infants.
