Development, Disturbances, and Training of Respiratory Regulation in Infants

Respiratory regulation is achieved under the command of the pH/pCO2- sensitive mechanism supported by the oxygen-sensitive drive. The central and peripheral chemoreceptor mechanisms define the pH range by which the neural respiratory control system is able to perform respiratory adaptations to the various demands of the body whether it is resting or exercising. Arterial pCO2, pH, pO2, and the precisely controlled acid-base range behind the blood-brain barrier from adequate stimuli for the sensor elements within the chemical feedback loop of breathing [10]. The respiratory drive is linked to the afferent and efferent motor system; in the adult its quantitative contribution under extreme conditions of exercise greatly exceeds the effect of chemical inputs to the respiratory generator. The motor system is immature in the newborn infant, as well as the efferent respiratory apparatus. The high respiratory resistance of the airways in the newborn and younger infant needs a precisely coordinating and powerful output of the central respiratory system. This is guaranteed by its main input from the peripheral and central chemoreceptors, whereas the vagal mechanisms have to economize the respiratory effort and to protect the airway system. Further important neural activity is formed by the manifold traffic from the descending and ascending reticular formation. The involvement of the latter in the sleep-waking cycle and its own developmental program during early life afford considerable adaptational maneuvers with maturation after birth. The specific linkages of the respiratory, cardiovascular, and temperature control systems and the connection of the complex programs of the higher brain functions with the respiratory system have to mature as well. Changing influences of various inputs in the central respiratory system with maturation one has aware of, since trigeminal afferents and nasal and other upper airway receptors play a more prominent role in early life than later on [1].