Regional ventilation distribution in non‐sedated spontaneously breathing newborns and adults is not different

Abstract

The speculated reverse pattern of regional ventilation distribution in healthy infants compared to adults could not be demonstrated. Gravity had little effect on ventilation distribution in both infants and adults measured in supine and prone position.

Changes in lung volume and ventilation following transition from invasive to noninvasive respiratory support and prone positioning in preterm infants

“…Our study showed that application of CDP via the endotracheal or nasal route did not impact ventilation distribution in these spontaneously breathing preterm infants. Comparable to other studies (28,30), ventilation slightly favored the dorsal lung regions. However, and in contrast to a previous study (30), placing the infants in prone position resulted in a clear shift in ventilation distribution to the ventral, dependent lung regions.…”

“…It has been suggested that this pattern only applies to sedated and mechanically ventilated infants. In spontaneously breathing infants, ventilation is distributed much more evenly throughout the lung (28,29). Our study showed that application of CDP via the endotracheal or nasal route did not impact ventilation distribution in these spontaneously breathing preterm infants.…”

“…The paradigm that ventilation distribution in infants follows a reversed pattern compared to adults with a preferable distribution to the nondependent (uppermost) lung has recently been challenged (28)(29)(30)(31). It has been suggested that this pattern only applies to sedated and mechanically ventilated infants.…”

Effect of time and body position on ventilation in premature infants

“…This change was significant only in the posterior lung despite the different positions. Previous studies have also shown ventilation distribution favoring the posterior (dorsal) lung regions (13,14,18,25). It has been reported that the utilization of PEEP redistributes ventilation toward the dependent areas of the lungs (26) although PEEP redistributes pulmonary perfusion to dependent lung regions in patients who are supine but not in prone (27).…”

“…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). The underlying anatomical structure of the lung is now considered one of the most important factors in causing heterogeneity in pulmonary perfusion and ventilation in both healthy and diseased lungs (20).…”