Extracorporeal machine liver perfusion: are we warming up?

Area of Science:

• Transplantation immunology
• Organ preservation techniques
• Hepatobiliary surgery

Background:

• Ex vivo machine perfusion is increasingly used for abdominal organ transplant.
• Hypothermic perfusion is the standard for liver preservation.
• The suitability of hypothermic perfusion for suboptimal livers is debated.

Purpose of the Study:

• To evaluate the efficacy of hypothermic versus normothermic ex vivo perfusion for liver grafts.
• To determine if warmer perfusion temperatures improve outcomes for suboptimal quality livers.

Main Methods:

• Review of current literature on ex vivo liver perfusion techniques.
• Comparative analysis of hypothermic and normothermic perfusion outcomes.
• Assessment of cellular injury markers and graft viability.

Main Results:

• Hypothermic perfusion (0-4°C) benefits normal livers by improving hepatocellular energy charge.
• Suboptimal livers perfused hypothermically show significant endothelial and Kupffer cell injury.
• Perfusion of suboptimal livers at higher temperatures (approaching 37°C) with adequate oxygen improves outcomes.

Conclusions:

• Normothermic perfusion provides physiological conditions, including oxygen and metabolic substrates.
• Normothermic perfusion appears to be the optimal strategy for enhancing the viability of suboptimal donor livers in transplantation.