Development of an artificial placenta V: 70 h veno-venous extracorporeal life support after ventilatory failure in premature lambs

Abstract

PurposeAn artificial placenta would change the paradigm of treating extremely premature infants. We hypothesized that using a veno-venous extracorporeal life support (VV-ECLS) artificial placenta after ventilatory failure would stabilize premature lambs and maintain normal fetal physiologic parameters for 70h. MethodsA near-term neonatal lamb model (130days; term=145) was used. The right jugular vein (drainage) and umbilical vein (reinfusion) were cannulated with 10–12 Fr cannulas. Lambs were then transitioned to an infant ventilator. After respiratory failure, the endotracheal tube was filled with amniotic fluid, and VV-ECLS total artificial placenta support (TAPS) was initiated. Lambs were maintained on TAPS for 70h. ResultsSix of seven lambs survived for 70h. Mean ventilation time was 57±22min. During ventilation, mean MAP was 51±14mmHg, compared to 44±14mmHg during TAPS (p=0.001). Mean pH and lactate during ventilation were 7.06±0.15 and 5.7±2.3mmol/L, compared to 7.33±0.07 and 2.0±1.8mmol/L during TAPS (p<0.001 for both). pO2 and pCO2 remained within normal fetal parameters during TAPS, and mean carotid blood flow was 25±7.5mL/kg/min. Necropsy showed a patent ductus arteriosus and no intracranial hemorrhage in all animals. ConclusionsThe artificial placenta stabilized premature lambs after ventilatory failure and maintained fetal circulation, hemodynamic stability, gas exchange, and cerebral perfusion for 70h.