Venoarterial Extracorporeal Membrane Oxygenation Increased Immune Function of Spleen and Decreased Reactive Oxygen Species During Post-Resuscitation.

We aimed to investigate the effect of venoarterial extracorporeal membrane oxygenation (VA-ECMO) on immune function of the spleen and reactive oxygen species (ROS) during post-resuscitation in a porcine model. After 8 min of untreated ventricular fibrillation and 6 min of basic life support, pigs were randomized into two groups: Group 1 received VA-ECMO and Group 2 received conventional cardiopulmonary resuscitation. After successful return of spontaneous circulation, the hemodynamic status was determined and blood samples were collected at 0, 1, 2, 4, and 6 h. Surviving pigs were euthanized 6 h after return of spontaneous circulation, their spleens were harvested and the T-cells were separated. Then, we investigated immune function parameters of the spleen and ROS levels. VA-ECMO increased the return of spontaneous circulation and 6 h survival rate after return of spontaneous circulation. Compared with the conventional cardiopulmonary resuscitation group, the VA-ECMO group showed increased superoxide dismutase and decreased malondialdehyde and ROS levels. Furthermore, VA-ECMO was associated with a high rate of CD4+ and CD4+/CD8+, high levels of interleukin 2, interferon γ, and interferon γ/interleukin 4, as well as high proliferation of lymphocytes. The apoptotic rate of T-cells was lower in the VA-ECMO group than it was in the conventional cardiopulmonary resuscitation group. VA-ECMO increased immune function of spleen and decreased ROS levels during post-resuscitation. Further research is expected to illustrate whether the differences in immune responses are due to ROS or some other perfusion related effect on spleen.