The artificial placenta: Continued lung development during extracorporeal support in a preterm lamb model

J Pediatr Surg. 2018 Oct;53(10):1896-1903. doi: 10.1016/j.jpedsurg.2018.06.001. Epub 2018 Jun 8.

Abstract

Purpose: An artificial placenta (AP) utilizing extracorporeal life support (ECLS) could avoid the harm of mechanical ventilation (MV) while allowing the lungs to develop.

Methods: AP lambs (n = 5) were delivered at 118 days gestational age (GA; term = 145 days) and placed on venovenous ECLS (VV-ECLS) with jugular drainage and umbilical vein reinfusion. Lungs remained fluid-filled. After 10 days, lambs were ventilated. MV control lambs were delivered at 118 ("early MV"; n = 5) or 128 days ("late MV"; n = 5), and ventilated. Compliance and oxygenation index (OI) were calculated. After sacrifice, lungs were procured and H&E-stained slides scored for lung injury. Slides were also immunostained for PDGFR-α and α-actin; alveolar development was quantified by the area fraction of alveolar septal tips staining double-positive for both markers.

Results: Compliance of AP lambs was 2.79 ± 0.81 Cdyn compared to 0.83 ± 0.19 and 3.04 ± 0.99 for early and late MV, respectively. OI in AP lambs was lower than early MV lambs (6.20 ± 2.10 vs. 36.8 ± 16.8) and lung injury lower as well (1.8 ± 1.6 vs. 6.0 ± 1.2). Double-positive area fractions were higher in AP lambs (0.012 ± 0.003) than early (0.003 ± 0.0005) and late (0.004 ± 0.002) MV controls.

Conclusions: Lung development continues and lungs are protected from injury during AP support relative to mechanical ventilation.

Level of evidence: n/a (basic/translational science).

Keywords: Artificial placenta; Extracorporeal life support; Lung development; Prematurity.

MeSH terms

  • Animals
  • Animals, Newborn
  • Artificial Organs*
  • Disease Models, Animal
  • Extracorporeal Membrane Oxygenation*
  • Female
  • Gestational Age
  • Lung / growth & development*
  • Lung / physiology
  • Placenta / physiology
  • Pregnancy
  • Premature Birth / therapy*
  • Sheep