The assessment of liver viability/injury based on ATP quantification of liver tissue at baseline and normothermic machine perfusion.

BACKGROUND

Orthotopic liver transplantation is a life-saving procedure for patients with end-stage liver disease. However, liver graft preservation remains a challenge, limited by ischemia-reperfusion injury. Normothermic machine perfusion (NMP) has emerged as a promising alternative. This study aimed to evaluate the functional viability and histological integrity of porcine livers preserved using an indigenously developed, costeffective NMP machine, and to correlate ATP depletion with liver injury during perfusion.

METHODS

Four Yorkshire pigs (35-40 kg) underwent liver retrieval and ex-situ perfusion using a custom-designed NMP. Liver function was monitored through bile production, lactate levels, blood gas analysis, and liver enzymes at 1-hour intervals over 8 hours. Liver biopsies were taken at baseline, 4 hours, and 8 hours for histopathological analysis and adenosine triphosphate (ATP) quantification using immunohistochemistry. ATP depletion was evaluated as a marker of liver viability.

RESULTS

The machine maintained functional viability, evidenced by stable bile production and minimal liver enzyme elevation, despite ATP depletion. Histopathological analysis revealed minimal damage in livers with < 50% ATP depletion, while significant injury (necrosis) was observed in livers with > 50% ATP depletion. ATP depletion correlated with functional impairment and liver injury, suggesting its potential as a predictive marker for liver viability.

CONCLUSION

The indigenously developed NMP machine effectively preserved liver function and structural integrity in porcine livers. ATP depletion is a reliable indicator of liver viability, and this system holds promise for improving graft preservation in liver transplantation, particularly for marginal grafts. Further studies with larger sample sizes are necessary for clinical validation.