Integrated stress response activation after recovery of cardiopulmonary bypass in rats

Background The systemic inflammation response syndrome (SIRS) is a consequence of the cardiopulmonary bypass (CPB) in cardiac surgery that can trigger multiple organ dysfunction (MOD). Pulmonary, renal and cerebral dysfunctions are the most common post-operative complications of CPB. The sustained of activation of integrated stress response (ISR) pathway could impact patient outcomes. Aim This project aims to decipher pathophysiological process in SIRS and organ dysfunction after recovery of CPB in a rat model. Methods After isoflurane induction (2%, O2: 0.5 L/min) surgical procedure for CPB or Sham was performed under propofol-fentanyl infusion (30–4 μg/kg/h) on mechanically ventilated 15-week old rats. The CPB circuit allows blood to be drawn by the vena cava and reperfused in the aorta after oxygenation. Hemodynamic and biochemical parameters were monitored during the procedure. Mean Arterial Pressure (MAP) was maintained to a minimum of 60 mmHg with a FiO2 1.0 for 1 h. Five hours post-recovery, behavior, respiratory rate and hemodynamic were measured. Blood and organs were collected to evaluate the integrated stress response pathway. Results Compared to Sham, CPB leads to a decrease of MAP (88.3 ± 2.6 vs 60.0 ± 9.4 mmHg, P Conclusion On our CPB rat model, we highlight organs dysfunctions associated with an activation of the ISR pathway. We will now evaluate the potential impact of ISR activation on MOD.