Regional Ventilation in Infancy. Reversal of Adult Pattern

Distribution of tidal ventilation during volume-targeted ventilation is variable and influenced by age in the preterm lung

“…Regional ventilation has previously been shown to be preferentially distributed to the non-dependent (uppermost) lung in infants and children with abnormal lungs [41] and in animal models of neonatal lung disease [10]. Our study found that most of the DZ VT occurred in the middle third of the anterior-posterior axis, with little difference between the most anterior and posterior regions.…”

Distribution of lung ventilation in spontaneously breathing neonates lying in different body positions

“…However, the largest problem of studies on subjects in this age group is the fact that neonates are non-cooperative. In view of these considerations it is no wonder that our knowledge on the spatial distribution of lung ventilation and the effect of body posture on respiration in neonates is limited to data obtained in sedated or anaesthetised infants [17,18,19], in infants with lung [17,19,20] or other disease [18], during mechanical ventilation [18,19,20] and in subject groups with large age heterogeneity [17,18,21].…”

“…In the elderly, a reversal of this pattern of distribution of inspired air in lungs occurs due to the loss of lung elastic recoil and collapse of lung regions [15,22]. A reversal of the adult pattern has also been postulated in infants and it was established in the right and left decubitus positions by gamma camera scanning in a group of mostly ill and mechanically ventilated infants [21]. In our study, no significant differences between the ventilation of the dependent and non-dependent lungs were found in the right lateral posture during rapid tidal breathing, which means that the distribution of inspired air was dissimilar from the adult pattern but it was not reversed.…”

Effect of time and body position on ventilation in premature infants

“…In the past, gravity has been considered the predominant influence on ventilation distribution in neonates (16,17). However, recent studies have shown that ventilation distribution of the neonate is less dependent on gravity, but more dependent on some complex anatomical factors (13)(14)(15)18,19).…”