Performance of an intravenous gas exchanger (IVOX) in a venovenous bypass circuit

Weike Tao, Joseph B. Zwischenberger, Thuan T. Nguyen, Alexander E. Tzouanakis, Edward J. Matheis, Daniel L. Traber, Akhil Bidani

Research output: Contribution to journalArticle

12 Scopus citations


To analyze quantitatively the performance of the intravenacaval blood gas exchanger (IVOX), we developed a right atrium-pulmonary artery venovenous extracorporeal bypass circuit Oxygen transfer and carbon dioxide removal were calculated at different blood flow rates, different hemoglobin levels, and during permissive hypercapnia. Oxygen transfer increased linearly with blood flow up to 41 mL/min. Likewise, O2 transfer increased linearly with hemoglobin levels up to 7. 5 g/dL, but no further increases were achieved above this level. Carbon dioxide removal increased linearly as flow increased from 1.0 to 3.0 L/min but did not increase further for higher flows. Carbon dioxide removal was 45 mL/min at blood carbon dioxide tension of 42 mm Hg but increased to a maximum of 81 mL/min at a carbon dioxide tension of 90 mm Hg. We conclude that IVOX is a diffusion-limited device dependent on blood flow, hemoglobin content, and the gas pressure gradient across the membrane. Further engineering improvements are needed to improve the gas exchange performance of IVOX.

Original languageEnglish (US)
Pages (from-to)1484-1491
Number of pages8
JournalThe Annals of Thoracic Surgery
Issue number6
Publication statusPublished - Jun 1994


ASJC Scopus subject areas

  • Surgery
  • Cardiology and Cardiovascular Medicine

Cite this

Tao, W., Zwischenberger, J. B., Nguyen, T. T., Tzouanakis, A. E., Matheis, E. J., Traber, D. L., & Bidani, A. (1994). Performance of an intravenous gas exchanger (IVOX) in a venovenous bypass circuit. The Annals of Thoracic Surgery, 57(6), 1484-1491.