Serial chest radiographs were performed on twenty infants who received partial liquid ventilation (PLV) with radiodense perflubron (LiquiVent™, Alliance Pharmaceutical Corp, San Diego). Infants (gest. age 24-42 wks) were less than 30 days of age with severe respiratory failure from multiple etiologies including respiratory distress syndrome, congenital diaphragmatic hernia (CDH), sepsis, and pneumonia. They were enrolled consecutively in one of four multicenter IRB-approved study protocols, and were supported by conventional and high frequency ventilation or ECMO at baseline and during PLV. PLV was initiated by instilling a volume of perflubron approximating functional residual capacity, estimated by the presence of a perflubron meniscus in the endotracheal tube. Perflubron was added periodically to maintain a meniscus. Results: Perflubron distribution during filling appeared homogeneous in preterm infants and infants with CDH, and patchy in other term infants. Non-CDH infants on ECMO showed the most pronounced heterogeneity, with large unfilled segments and marked delay of alveolarization with persistence of perflubron in large airways as compared to preterm infants. Radiographically, liquid lung volume increased during the period of PLV as compared with the initial filling volume in most infants. Evaporative patterns were generally uneven in all groups, with segmental retention in most term infants. Up to 90 percent of lung fields showed clearance of perflubron within 24 hours of the last dose, with varying amounts of residual perflubron for months s/p PLV. Patterns of residual perflubron varied with initial disease, were patchy in term infants and appeared to be interstitial in some preterm infants. We conclude that radiographic filling patterns in infants receiving PLV vary with the primary disease, and are more homogeneous in preterm than in term infants. Evaporative patterns were patchy for all infants studied.

Consulting agreements and funding in part by Alliance Pharm. Corp. and Hoechst Marion Roussel.