Bench Validation of a Compact Low-Flow CO2 Removal Device

Alexandra G May; R Garrett Jeffries; Brian J Frankowski; Greg W Burgreen; William J Federspiel

doi:10.1186/s40635-018-0200-7

Bench Validation of a Compact Low-Flow CO₂ Removal Device

Intensive Care Med Exp. 2018 Sep 24;6(1):34. doi: 10.1186/s40635-018-0200-7.

Authors

Alexandra G May^{1

2}, R Garrett Jeffries^{2

3}, Brian J Frankowski², Greg W Burgreen⁴, William J Federspiel^{5

6

7

8}

Affiliations

¹ Department of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, USA.
² McGowan Institute for Regenerative Medicine, University of Pittsburgh, 3025 East Carson Street, Suite 226, Pittsburgh, PA, 15203, USA.
³ Department of Bioengineering, University of Pittsburgh, Pittsburgh, USA.
⁴ Computational Fluid Dynamics Group, Center for Advanced Vehicular Systems, Mississippi State University, Mississippi State, MS, USA.
⁵ Department of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, USA. wfedersp@pitt.edu.
⁶ McGowan Institute for Regenerative Medicine, University of Pittsburgh, 3025 East Carson Street, Suite 226, Pittsburgh, PA, 15203, USA. wfedersp@pitt.edu.
⁷ Department of Bioengineering, University of Pittsburgh, Pittsburgh, USA. wfedersp@pitt.edu.
⁸ Department of Critical Care Medicine, University of Pittsburgh Medical Center, Pittsburgh, USA. wfedersp@pitt.edu.

Abstract

Background: There is increasing evidence demonstrating the value of partial extracorporeal CO₂ removal (ECCO₂R) for the treatment of hypercapnia in patients with acute exacerbations of chronic obstructive pulmonary disease and acute respiratory distress syndrome. Mechanical ventilation has traditionally been used to treat hypercapnia in these patients, however, it has been well-established that aggressive ventilator settings can lead to ventilator-induced lung injury. ECCO₂R removes CO₂ independently of the lungs and has been used to permit lung protective ventilation to prevent ventilator-induced lung injury, prevent intubation, and aid in ventilator weaning. The Low-Flow Pittsburgh Ambulatory Lung (LF-PAL) is a low-flow ECCO₂R device that integrates the fiber bundle (0.65 m²) and centrifugal pump into a compact unit to permit patient ambulation.

Methods: A blood analog was used to evaluate the performance of the pump at various impeller rotation rates. In vitro CO₂ removal tested under normocapnic conditions and 6-h hemolysis testing were completed using bovine blood. Computational fluid dynamics and a mass-transfer model were also used to evaluate the performance of the LF-PAL.

Results: The integrated pump was able to generate flows up to 700 mL/min against the Hemolung 15.5 Fr dual lumen catheter. The maximum vCO₂ of 105 mL/min was achieved at a blood flow rate of 700 mL/min. The therapeutic index of hemolysis was 0.080 g/(100 min). The normalized index of hemolysis was 0.158 g/(100 L).

Conclusions: The LF-PAL met pumping, CO₂ removal, and hemolysis design targets and has the potential to enable ambulation while on ECCO₂R.

Keywords: Acute respiratory distress syndrome; Artificial lung; COPD; Extracorporeal CO2 removal.

Abstract

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