Objective:To investigate the effects of veno-venous bypass during orthotopic liver transplantation in pig on hemodynamics and blood biochemistry. Methods: The study was performed on 12 elected healthy pigs ±(weighted 25.502.10kg) under intravenous anesthesia. The catheter was inserted through the right jugular vein and right carotic artery for measurement of hemodynamic parameters; the right carotic artery was cannulated for blood pressure monitoring and blood gases samples.The veno-venous bypass was done during anhepatic stage. Results: Applying the veno-venous bypass during anhepatic stage could keep hemodynamics stable

but in 5-10 min of the primary anheptic and neoheptic stages

the hemodynamics was very unstable; and blood gases BE and HCO3 dropped during anhepatic; hypocalcemia was significant. Conclusion: The veno-venous bypass during anhepatic stage can be of help to maintain hemodynamics stable; but in the primary anhepatic and neohepatic stage hemodynamic instablity occurred

and changes of blood gases and electrolyces level were considerable.