The role of veno-venous bypass in liver transplant

Veno-venous bypass (VVB) ensures end-organ perfusion and minimizes splanchnic venous congestion during liver transplant procedures. The adoption of the piggyback technique, where flow through the inferior vena cava is preserved, has prompted a decline in the routine use of VVB. Meanwhile, recommendations on VVB use in liver transplantation remain equivocal. This article explores the clinical implications of VVB use in liver transplantation and offers a comprehensive analysis of its benefits and risks in the context of recent surgical advancements.

Evidence indicates that patients undergoing complex procedures or with baseline renal dysfunction may benefit from VVB for conventional liver resection, emphasizing the need for careful patient selection. By contrast, small, retrospective studies suggest lower transfusion requirements and improved graft survival when the piggyback approach was used without VVB, but evidence remains sparse. While direct bypass cannulation-associated complications remain a concern, technical advancements have made VVB use increasingly safe.

In conclusion, VVB remains an important tool in selected, high-acuity patients, but offers limited benefit in more stable patients undergoing piggyback liver resection. Large-scale randomized studies are needed to elucidate the benefit of VVB in selected patient populations undergoing procedures with different surgical approaches.