Seven-day in vivo testing of a novel, low-resistance, pumpless pediatric artificial lung for long-term support

Introduction: For children with end-stage lung disease that cannot wean from extracorporeal life support (ECLS), a wearable artificial lung would permit extubation and provide a bridge to recovery or transplan-tation. We evaluate the function of the novel Pediatric MLung-a low-resistance, pumpless artificial lung developed specifically for children-in healthy animal subjects.Methods: Adolescent mini sheep weighing 12-20 kg underwent left thoracotomy, cannulation of the main pulmonary artery (PA; inflow) and left atrium (outflow), and connection to the MLung. Results: Thirteen sheep were studied; 6 were supported for 7 days. Mean PA pressure was 23.9 +/- 6.9 mmHg. MLung blood flow was 633 +/- 258 mL/min or 30.0 +/- 16.0% of CO. MLung pressure drop was 4.4 +/- 3.4 mmHg. Resistance was 7.2 +/- 5.2 mmHg/L/min. Device outlet oxygen saturation was 99.0 +/- 3.3% with inlet saturation 53.8 +/- 7.3%. Oxygen delivery was 41.1 +/- 18.4 mL O2/min (maximum 84.9 mL/min) or 2.8 +/- 1.5 mL O2/min/kg. Platelet count significantly decreased; no platelet transfusions were required. Plasma free hemoglobin significantly increased only on day 7, at which point 2 of the animals had plasma free hemoglobin levels above 50 mg/dL. Conclusion: The MLung provides adequate gas exchange at appropriate blood flows for the pediatric pop-ulation in a PA-to-LA configuration. Further work remains to improve the biocompatibility of the device. Level of evidence: N/A (c) 2022 Elsevier Inc. All rights reserved.

Automated summary

This study evaluated the function of a low-resistance, pumpless artificial lung (MLung) developed specifically for children in healthy animal subjects. The results showed that MLung provides adequate gas exchange at appropriate blood flows in a PA-to-LA configuration. However, further improvements are needed to enhance the biocompatibility of the device.