IMPORTANCE OF HEPATOVENOUS BACK-PERFUSION FOR MAINTENANCE OF LIVER VIABILITY DURING THE PRINGLE MANEUVER

The role of hepatovenous back-perfusion in maintaining hepatic viabili ty was investigated during inflow occlusion (Pringle manoeuvre) of the pig liver. The study compared two ischaemia procedures of 60 min dura tion: hepatic inflow occlusion and inflow plus outflow occlusion (vasc ular exclusion). Each procedure was carried out in six pigs and liver tissue perfusion, energy metabolism, lipid peroxidation and 7-day surv ival were assessed. Although all pigs survived after inflow occlusion, five of six died after vascular exclusion (P < 0.01). Exclusion induc ed a significant decrease in perfusion to 15.3 per cent of the value b efore ischaemia compared with 32.4 percent after hepatic inflow occlus ion alone (P < 0.01). Although cellular adenosine 5'-triphosphate leve ls were significantly decreased by ischaemia in both groups, the fall was less in pigs with inflow occlusion alone (to 55 per cent of the pr eclamp value) than in those with exclusion (to 24 per cent of the prec lamp value) (P < 0.01). The plasma phosphatidylcholine hydroperoxide l evel rose immediately after reperfusion in pigs with exclusion, while the level remained constant after inflow occlusion alone. There is a f undamental difference between the two ischaemia procedures: back-perfu sion from the vena cava contributes to the maintenance of liver functi on during inflow occlusion.