Regional distribution of blood volume within the preterm infant thorax during synchronised mechanical ventilation

Purpose Perfusion in healthy adults is gravity-dependent. Little is known about lung perfusion in the preterm infant. The aim of this study was to describe the regional distribution of blood volume within the thorax in preterm infants receiving synchronised volume-targeted mechanical ventilation (SIPPV + TTV) and to compare this to regional distribution of tidal ventilation using electrical impedance tomography (EIT). Methods Stable supine ventilated preterm infants (7 days) and oxygen requirement. Results A total of 5,471 beats were analysed from 26 infants (78 recordings); mean (standard deviation (SD)) gestational age was 26 (2) weeks and mean (SD) postnatal age was 9 (10) days. The median (interquartile range) Δ Z c in the anterior half of the hemithorax was 1.41-fold (0.88–2.11) greater than that in the posterior half. The geometric centre of Δ Z c was located at 46.7% of the anterior-posterior thoracic distance, compared to a more centrally located Δ Z v (49.6%; p