A mathematical model of oxygenation during venovenous extracorporeal membrane oxygenation support

作者：Zanella Alberto^*; Salerno Domenico; Scaravilli Vittorio; Giani Marco; Castagna Luigi; Magni Federico; Carlesso Eleonora; Cadringher Paolo; Bombino Michela; Grasselli Giacomo; Patroniti Nicolo; Pesenti Antonio

来源：Journal of Critical Care, 2016, 36: 178-186.

DOI：10.1016/j.jcrc.2016.07.008

• Extracorporeal circulation
• Extracorporeal membrane oxygenation
• Oxygen consumption
• Blood circulation
• Cardiac output
• Theoretical models

Purpose: To develop a mathematical model of oxygenation during venovenous extracorporeal membrane oxygenation (vv-ECMO).
Material and methods: Total oxygen consumption, cardiac output, blood flow, recirculation, intrapulmonary shunt, hemoglobin, natural lung, and membrane lung oxygen fractions were chosen as inputs. Content, partial pressure, and hemoglobin saturation of oxygen in arterial, venous, pulmonary, and extracorporeal blood were outputs. To assess accuracy and predictive power of the model, we retrospectively analyzed data of 25 vv-ECMO patients. We compiled 2 software (with numerical, 2D and 3D graphical outputs) to study the impact of each variable on oxygenation.
Results: The model showed high accuracy and predictive power. Raising blood flow and oxygen fraction to the membrane lung or reducing total oxygen consumption improves arterial and venous oxygenation, especially in severe cases; raising oxygen fraction to the natural lung improves oxygenation only in milder cases; raising hemoglobin always improves oxygenation, especially in the venous district; recirculation fraction severely impairs oxygenation. In severely ill patients, increasing cardiac output worsens arterial oxygenation but enhances venous oxygenation. Oxygen saturation of ECMO inlet is critical to evaluate the appropriateness of oxygen delivery.
Conclusions: The model with the software can be a useful teaching tool and a valuable decision-making aid for the management of hypoxic patients supported by vv-ECMO.

• 出版日期2016-12