Respiratory failure is a significant problem within the pediatric population. A means of respiratory support that readily allows ambulation could improve treatment. The Pittsburgh Pediatric Ambulatory Lung (P-PAL) is being developed as a wearable pediatric pump-lung for long-term respiratory support and has previously demonstrated positive benchtop results. This study aimed to evaluate acute (4–6 hours) in vivo P-PAL performance, as well as develop an optimal implant strategy for future long-term studies. The P-PAL was connected to healthy sheep (n = 6, 23–32 kg) via cannulation of the right atrium and pulmonary artery. Plasma-free hemoglobin (PfHb) and animal hemodynamics were measured throughout the study. Oxygen transfer rates were measured at blood flows of 1–2.5 L/min. All animals survived the complete study duration with no device exchanges. Flow limitation because of venous cannula occlusion occurred in trial 2 and was remedied via an altered cannulation approach. Blood exiting the P-PAL had 100% oxygen saturation with the exception of trial 4 during which inadequate device priming led to intrabundle clot formation. Plasma-free hemoglobin remained low (<20 mg/dl) for all trials. In conclusion, this study demonstrated successful performance of the P-PAL in an acute setting and established the necessary methods for future long-term evaluation.
From the *McGowan Institute for Regenerative Medicine, Pittsburgh, Pennsylvania
†Department of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania
‡Department of Cardiothoracic Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania
§Cardiac Center, Nemours Children’s Hospital, Orlando, Florida
¶Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania
‖Department of Critical Care Medicine, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania.
Submitted for consideration May 2018; accepted for publication in revised form October 2018.
Disclosure: W.J.F. chairs the Scientific Advisory Board and is a founder of ALung Technologies, in which he has an equity interest. No other authors have a conflict of interest to report.
This work was supported by National Institutes of Health (NIH) Grant R01HL135482-01 and the McGowan Institute for Regenerative Medicine. A.G.M. was supported by an NIH training grant (T32 HL076124) for the University of Pittsburgh Cardiovascular Bioengineering Training Program.
Correspondence: William J. Federspiel, McGowan Institute for Regenerative Medicine, University of Pittsburgh, 3025 East Carson Street, Pittsburgh, PA 15203. Email: firstname.lastname@example.org.