Abstract:

Objective We used the principle of extracorporeal membrane oxygenation（ECMO）to assembleour own normothermic machine perfusion（NMP）system，and to verify the effect and stability of NMP in the split liver process of perfusion and preservation of Bama miniature pig. Methods Four healthy Bama miniature pig were selected，the liver was quickly harvested and was connected to the NMP device for preservation and perfusion. In the process of split，portal vein，hepatic artery flow and pressure，the temperature of liver preservation were recorded. Results During the liver splitting procedure, the portal vein pressure was maintained between 8.75- 9.75 mmHg（1 mmHg ＝ 0.133 kPa）. Meanwhile, the hepatic artery pressure was maintained in a range of 92.00- 92.75 mmHg. In the splitting process, portal venous flow reduced from（455.00±107.55）mmHg before splitting to （392.50±125.27）mmHg after splitting, while hepatic artery flow reduced from（180.75±59.46）mmHg before splitting to（126.25±6.99）mmHg after splitting. Before splitting, the pH value（7.24±0.10）was lower than the baseline value（7.50±0.08）, and it gradually increased with splitting and reached a value of（7.60±0.13）after splitting, which was slightly higher than the baseline value. The PO2 was maintained in a range of 482.25-521.00 mmHg during splitting, which was significantly higher than the baseline value（304.00±78.11）mmHg. HCO3 - was（10.10± 5.04）mmol/L before splitting，which was significantly lower than the baseline value of（24.05±0.31）mmol/L， while it gradually increased. Na + was maintained in a range of 142.75-149.25mmol/L during splitting. During the preservation splitting，K+ gradually increased from（3.45±0.33）mmol/L at baseline to（4.98±1.12）mmol/L at the end of splitting. Before splitting, the lactic acid was（2.86±1.77）mmol/L, which was lower than the baseline value of （3.85±2.58）mmol/L，and it gradually increased to（6.00±3.73）mmol/L at the end of splitting. The bile secretion was gradually reduced with splitting before splitting ：（16.75±3.30）ml/h, during splitting ：（10.55±1.83）ml/h，and after splitting ：（6.53±1.33）ml/h. At the beginning of perfusion preservation，the alanine aminotransferase（ALT）， lactate dehydrogenase（LDH），and alkaline phosphatase（ALP）were lower than the baseline level. ALT and LDH gradually increased with splitting，whereas ALP was maintained in a lower level in the splitting. At the beginning of perfusion preservation, aspartate aminotransferase（AST）was comparable with the baseline value，and it was gradually increased with splitting. The cell structure in the liver did not show significant changes after splitting with NMP preservation compared with that before the preservation. Conclusion Our NMP system in the process of liver splitting is relatively stable，with a certain clinical value.