Dynamic Pressure‐volume Relationship of the Lung and Position in Healthy Neonates

Abstract

Summary There is no significant difference in the dynamic V/P loops of the lung between supine position with the head in normal median position, and prone position, i.e. when there is no deformation of the upper airways. In both prone and supine position with flexion or rotation of the head, the slope of the V/P loops was decreased and the width of the loops in creased. In pulmonary function tests special attention should therefore be given to the position of the head in relation to the body.

Effect of Prone and Supine Positions on Functional Residual Capacity, Oxygenation, and Respiratory Mechanics in Ventilated Infants and Children

“…R rs does vary inversely with lung volume (26,27), but FRC did not change significantly in this subgroup of patients. A decrease in R L in the prone position was reported by Mendoza and colleagues (11), although most authors have found no change (6)(7)(8)10). To the best of our knowledge this is the first study to measure positional changes in R rs in patients with severe obstructive disease.…”

“…Although many authors hypothesize the improvement in oxygenation is due to an increase in functional residual capacity (FRC) (4,5,9) there are no published studies documenting positional changes in FRC in children with severe lung disease. A number of investigators have examined pulmonary mechanics in the prone and supine positions (6)(7)(8)(9)(10)(11). However these studies have largely been carried out in spontaneously breathing neonates (some intubated and some not) with, at worst, mild lung disease.…”

“…The prone position has also been advocated as being beneficial for a wide variety of non-pulmonary considerations, ranging from improved neurodevelopment in neonates (7) to the promotion of flatulence (8). Although many authors hypothesize the improvement in oxygenation is due to an increase in functional residual capacity (FRC) (4,5,9) there are no published studies documenting positional changes in FRC in children with severe lung disease.…”

Respiratory function measurements in infants: measurement conditions. Working Group of the European Respiratory Society and the American Thoracic Society

“…Although there appears to be little evidence that lung volume is position-dependent in the recumbent infant [12], mechanics and respiratory pattern do appear to be position-dependent, especially in the anaesthetized infant or one with respiratory disease [12][13][14][15][16][17][18].…”

Lung reflexes

“…intensive care (24). The inflation reflex, however, is more cOmInOn in infants with non-compliant lungs (10) and thus may be reduced by the improved lung function associated with prone positioning (23,24). a consequence, prone nursing may have a n adverse effect if reflexes are still an important respiratory control mechanism.…”