Clinical research on the pathogenesis and treatment of portal hemodynamics and pathological regeneration in small-for-size liver grafts after living donor liver transplantation: Pathogenesis and clinical innovation

尽管活体肝移植（LDLT）已被广泛接受为终末期肝病的治疗选择，但小尺寸移植物及其病理在许多项目中留下了许多争议。本研究重点探讨小尺寸移植物相关症状的发病机制，旨在建立有效、安全的治疗方式。术中经受体肠系膜下静脉置入抗血栓导管，术后2周直接监测门静脉压力（PVP）。与适当大小的移植物相比，小尺寸移植物普遍存在大量腹水、移植物再生延迟、凝血功能延长和胆汁淤积。在小尺寸移植物中发生的细菌易位可能是由于降低肝网状内皮功能或改变肠粘膜免疫。这些现象与PVP升高密切相关，且小尺寸移植物术中和术后PVP明显高于大尺寸移植物。结果显示PVP升高具有很强的预后价值，手术时开始脾动脉结扎（SAL）。SAL不仅能立即降低PVP，还能提高小尺寸移植物的累积受体存活率。同时，用磁共振成像研究移植物组织充血情况。80-90%的右移植物在没有额外引流重建的情况下出现与前段充血相一致的形态学改变。然而，在几个月后，大多数移植物的充血逐渐改善。移植物充血与肝功能恶化和PVP升高无关。然而，术后第三周或第四周的腹水量与第一个月的移植物总充血量之间存在初步但显著的正相关。总之，早期PVP升高与小尺寸移植物的不良预后密切相关。然而，SAL诱导PVP立即和持续减少，并对移植物和患者预后产生积极影响。少

Although living donor liver transplantation (LDLT) has been widely accepted as a treatment of choice for end-stage liver diseases, small-for-size grafts and their pathology leave many controversies in many programs. This study focused on pathogenesis of symptoms associated with small-for-size graft and aimed to establish the effective and safe treatment modality.An antithrombotic catheter was inserted via the inferior mesenteric vein of recipient during operation, and portal vein pressure (PVP) was directly monitored for two weeks after surgery. In small-for-size grafts, compared with appropriate-size grafts, massive ascites, delay of graft regeneration, prolonged coagulopathy and cholestasis were observed commonly. Bacterial translocation possibly attributable either to reduce hepatic reticuloendothelial function or to alter mucosal immunity of intestine occurred in small-for-size grafts. These phenomena closely associated with elevated PVP, and PVP in small-for-size grafts during and … More after operation was significantly higher than that in appropriate-size grafts. Based on the results suggesting that elevated PVP serve a strong prognostic value, splenic artery ligation (SAL) was initiated at operation. SAL induced not only an immediate reduction of PVP, but also cumulative recipient survival in small-for-size grafts was improved.In parallel, graft tissue congestion was investigated using magnetic resonance imaging. Morphologica1 changes compatible with congestion in the anterior segment occurred in 80-90% of right grafts without additional drainage reconstruction. However, congestion improved gradually in most grafts after several months. Graft congestion was associated with neither deteriorated liver function nor elevated PVP. However a tentative but significant positive correlation was observed between amount of ascites in the third or fourth week after surgery and total graft congestion in first month.In conclusion, elevated PVP in the early phase is strongly associated with poor prognosis attributable to small-for-size graft. However SAL induces an immediate and persistent reduction of PVP and gives positive effects on graft and patient prognosis. Less