门静脉动脉化在肝移植中的应用

用动脉血代替门静脉血灌注肝脏的设想最初是由Cohn( 1 95 2年 )和Fisher( 1 95 4年 )根据门静脉高压门腔分流术后肝脏血液灌注减少 ,术后肝性脑病发生率高而提出的[1 ,2 ] 。随后许多学者作了大量动物实验研究 ,证实用适当流量和压力的动脉血灌注肝内门静脉时 ,动物在分流术后可维持正常的肝血流量、血氨和血胆酸水平 ,保证肝脏的正常解毒功能 ,肝细胞形态保持不变。自从 1 960年以来 ,门静脉动脉化 (APV)的概念由于它的各种临床应用已经引起广泛的关注 ,在行端侧吻合门体分流治疗肝硬化的过程中 ,APV首先被临床应用去降低分流术后肝性…     

Portal vein arterialization in hepatobiliary surgery and liver transplantation

We reviewed the literature reports and our personal experience on partial portal vein arterialization (PPVA) to prevent and treat acute liver failure (ALF) following major hepatobiliary surgery or another etiology. Experimental studies in rats have assessed the efficacy of PPVA in treatment of ALF induced by extended resections in normal or fatty livers or in toxic carbon-tetrachloride damage. The treated groups showed greater survival and faster recovery of liver function. Among 11 clinical cases reported in the literature, PPVA was performed in four cases to prevent and in seven cases to treat ALF. Eight patients survived, showing rapid recovery of liver function and resolution of the clinical condition. This relatively simple procedure has shown itself able to promote liver regeneration. The PPVA procedure has shown itself to be safe and simple as well as to offer a promising approach to the failing liver.     

Primary permanent arterialization of the portal vein in liver transplantation

Permanent total arterialization of the portal vein in liver transplantation has been described as a method of providing portal inflow after insufficient thrombectomy due to chronic occlusion of the portal-vein system. A specific problem is the restriction of the arterial inflow and its long-term adaptation after transplantation. We describe here the surgical techniques and clinical course of three patients who underwent portal-vein arterialization for liver transplantation. Two patients had an uneventful course. In one patient, a flow reduction by means of coil embolization of one arterial inflow branch was performed; thereafter, the patient recuperated well. Analysing the microcirculation of an arterialized graft in comparison with liver grafts with normal non-arterialized portal-vein inflow, we observed an increase in inter-sinusoidal distance and a decrease in sinusoidal red blood cell velocity. From a technical point of view, we recommend permanent portal-vein arterialization by an iliac artery graft interposition from the subdiaphragmatic aorta. The inflow to the portal vein can easily be reduced by the banding of the arterial graft interposition.     

改良的套叠缝合重建肝动脉的大鼠原位肝移植模型

目的 介绍1种简便的套叠缝合重建肝动脉的大鼠原位肝移植模型。方法 采用套叠缝合重建肝动脉的大鼠原位肝移植模型20例。肝移植采用二袖套法，动脉重建利用供肝的肝总动脉与受体的肝固有动脉根部二针套叠缝合方法。结果 本方法建立大鼠原位肝移植模型的手术时间（包括供体手术）和重建动脉的时间明显缩短。大鼠30d存活率和肝动脉的通畅率均为100％。无胆道并发症发生。结论 套叠缝合重建肝动脉的大鼠原位肝移植模型简便、省时、成功率高，且对组织损伤小、更符合受体解剖生理。     

Temporary portal vein arterialization as an attractive option in canine orthotopic partial liver transplantation.

We performed 22 canine orthotopic partial liver transplantations (PLTs) with three different revascularization methods; portal vein arterialization (PVA group, n = 11), hepatic arterial shunt (HAS group, n = 5), and conventional portal vein reperfusion (control group, n = 6). Our purpose was to evaluate the feasibility of PVA as a revascularization technique in PLT assessing the changes in arterial ketone body ratio (KBR) as an index of hepatic energy status. After the first anastomosis (left hepatic vein), the ischemic partial liver graft was revascularized with arterial blood flow shunted from the external iliac artery to the hepatic side of the portal vein (PVA group) or the proper hepatic artery (HAS group). Both anhepatic period and ischemia time were significantly shortened in groups PVA and HAS as compared with those in control. In the PVA group, 10 out of 11 recipients survived for at least 5 days (14.2 +/- 3.8 days, mean +/- SEM), while 3 out of 5 (5.2 +/- 1.0) survived in the HAS group and 4 out of 6 (6.2 +/- 1.3) in the controls. Although portal blood flow during PVA was only about 25% of the total hepatic blood flow at preclamping, the KBR was rapidly restored after PVA and showed almost the same values at preclamping. The KBR values during the arterialization time and initial velocity of KBR recovery in the PVA group were significantly higher than those in the HAS and control groups. These results suggest that PVA presents an attractive option in PLT.     

Auxiliary rat liver transplantation with portal vein arterialization in acute hepatic failure

BACKGROUND: The aim of our work was to study the effect of the portal vein arterialization of an auxiliary liver graft on survival, liver function, and regeneration of the native liver suffering from surgically induced acute liver failure (ALF). METHODS: In Lewis rats (control group: n=10), ALF was induced by resection of about 85% of liver tissue. The auxiliary liver graft (reduced size of 30%) was transplanted into the right upper quadrant of the abdomen (trial group: n=12). The portal vein was arterialized via the renal artery. The infrahepatic vena cava was anastomosed end-to-side, and the bile duct was implanted into the duodenum. RESULTS: Survival rate over a 3-month period was 10/12 in the trial group vs. 2/10 in the controls. In the trial group, the prothrombin time rose up to 38+/-2 sec on day 1 after surgery (control group: 66+/-6 sec); on day 5 after surgery, it returned to values of 30+/-1 sec. On day 1 after surgery, serum albumin fell to 25+/-1 g/L (preoperative value: 32+/-1 g/L). Within 3 weeks, it returned to normal. The hepatobiliary scan on day 7 after surgery showed normal uptake in the liver graft, whereas the uptake of the native liver was distinctly reduced. After 3 months, the transplanted liver had atrophied (0.6% of body weight), the native liver hypertrophied (2.5% of body weight), with a normal total weight for both livers of 3.1% of body weight. CONCLUSIONS: Thus, auxiliary liver transplantation with arterialized portal vein allows maintenance of liver function at the time of ALF and regeneration of the native liver.     

Improved technique of heterotopic auxiliary rat liver transplantation with portal vein arterialization

BACKGROUND AND AIMS: In acute, potentially reversible hepatic failure, auxiliary liver transplantation is a promising alternative approach. Using the auxiliary partial orthotopic liver transplantation (APOLT) method--the orthotopic implantation of auxiliary segments--most of the technical problems (lack of space for the additional liver mass, the portal vein reconstruction, and the venous outflow) are avoided, but extensive resections of the native liver and the graft are necessary. Erhard described the heterotopic auxiliary liver transplantation (HALT) with portal vein arterialization (PVA). Initial clinical results demonstrated that an adequate liver function can be achieved using this technique. We developed and improved a technique of HALT with flow-regulated PVA in the rat to perform further investigations. The aim of this paper is to explain in detail this improved experimental surgical technique. MATERIALS AND METHODS: Liver transplantations were performed in 122 male Lewis rats: After a right nephrectomy, the liver graft, which was reduced to about 30% of the original size, was implanted into the right upper quadrant of the recipient's abdomen. The infrahepatic caval vein was anastomosed end-to-side. The donor's portal vein was completely arterialized to the recipient's right renal artery in stent technique. Using a stent with an internal diameter of 0.3 mm, the flow in the arterialized portal vein was regulated to achieve physiologic parameters. The celiac trunk of the graft was anastomosed to the recipient's aorta, end-to-side. The bile duct was implanted into the duodenum. RESULTS: After improvements of the surgical technique, we achieved a perioperative survival of 90% and a 6-week survival of 80% in the last 112 transplantations. CONCLUSION: We developed a standardized and improved technique, which can be used for experiments of regeneration and inter-liver competition in auxiliary liver transplantation. Furthermore, this technique is suitable for the investigation of the influence of portal vein arterialization and portal hyperperfusion on liver microcirculation, function, and morphology.     

The impact of arterialization on hepatic microcirculation and leukocyte accumulation after liver transplantation in the rat.

This study investigated the influence of hepatic arterialization on early graft function, microcirculation, and leukocyte-endothelial interaction after syngeneic orthotopic liver transplantation in Lewis rats. Livers were preserved for 17 hr in UW solution and transplanted without rearterialization (group 1: n = 10) or with immediate arterial reconstruction (group 2: n = 10). Graft function was analyzed by bile flow; microcirculation was assessed by laser Doppler flowmetry (LDF) and intravital microscopy (IVM). In addition, flow behavior of leukocytes was quantified by IVM after i.v. injection of the WBC marker acridine orange. Improved graft function in group 2 was indicated by increased bile production during the observation period of 90 min after reperfusion (7.18 +/- 0.62 vs. 3.63 +/- 0.63 ml/100 g liver [mean +/- SEM] P < 0.001). In arterialized grafts LDF values increased by 22.9 +/- 3.8% upon reperfusion of the hepatic artery (P = 0.004). Arterialization increased WBC velocities in sinusoids (group 1: 0.29 +/- 0.02 mm/sec, group 2: 0.34 +/- 0.01 mm/sec, P < 0.001) and postsinusoidal venules (0.43 +/- 0.05 vs. 0.64 +/- 0.05 mm/sec, P = 0.029). In addition, the number of nonperfused midzonal sinusoids decreased significantly (8.5 +/- 2.2% of all sinusoids analyzed vs. 4.2 +/- 1.3%, P = 0.048). However, the marked sinusoidal and venular WBC adherence observed 1 hr after reperfusion was not altered by arterialization. It is concluded that arterial reconstruction in rat liver transplantation improves microvascular perfusion and graft function but this improvement does not relate to WBC accumulation within the graft. We propose that studies on hepatic preservation and postischemic reperfusion in the rat should be based on the physiological model of dual vascularization.     

Clinical application of arterialization of portal vein in living related donor partial liver transplantation

Arterialization of the portal vein was employed during hepatic arterial reconstruction in our first few clinical experiences of partial liver transplantation using liver grafts obtained from living related donors. This procedure reduced the time required for revascularization of the grafts to about 25 min, and could in fact reduce the ischemic phase of the grafts. Repeated practice of the clinical transplantation technique has shortened the time needed to complete vascular reconstruction, eliminating the need for this procedure in most of our subsequent cases. In many clinical cases, however, there may be emergency situations which require vascular reconstruction, resulting in a prolongation of ischemic phase and the deterioration of the cellular viability of the graft. In such situations, arterialization of the portal vein can be a useful way to prevent the prolongation of the ischemic phase and to rescue the graft.     

Auxiliary liver transplantation with arterialization of the portal vein for acute hepatic failure

Six adult patients suffering from acute hepatic failure and with a high urgent status underwent heterotopic auxiliary liver transplantation. In four of these patients, the portal vein of the liver graft was arterialized in order to leave the native liver and the liver hilum untouched and to be able to place the liver graft wherever space was available in the abdomen. The arterial blood flow via the portal vein was tapered by the width of the anastomosis. Two patients died, one of sepsis on postoperative day 17 (POD), the other after 3 months due to a severe CMV pneumonia. There were no technically related deaths. The native liver showed early regeneration in all cases. In one patient, the auxiliary graft was removed 6 weeks after transplantation. Four weeks later, he had to undergo orthotopic retransplantation due to a recurrent fulminant failure of the recovered native liver. This patient is alive more than 1 year after the operation. We conclude that heterotopic auxiliary liver transplantation with portal vein arterialization is a suitable approach to bridging the recovery of the acute failing native liver. Received: 15 September 1997 Received after revision: 4 February 1998 Accepted: 2 March 1998     

Pathology findings in a model of auxiliary liver transplantation with portal vein arterialization in pigs

OBJECTIVE: To determine the histological findings and temporal evolution that occur in auxiliary liver grafts as a consequence of arterialization of the portal vein (PVA). MATERIALS AND METHODS: We evaluated 10 auxiliary heterotopic liver transplants with arterialization of the PVA. The histological study was performed using an optical microscope to process liver samples with staining using hematoxylin and eosin. A biopsy of native liver tissue was used as a control. RESULTS: Two animals were excluded from the study, one due to ischemic necrosis of the graft and one that died 4 hours after transplant. All of the remaining eight animals underwent a histological study at 1 day, 7 days, and 14 days. The most significant histological findings were: (1) dilation of portal areas and sinusoids, which were detected at 24 hours and persisted; (2) thickening of the interlobular septum, which was observed after day 7 and progressively increased to day 14; (3) bile duct hyperplasia detected at the seventh day. CONCLUSIONS: The consistent, early findings in a pig liver with PVA included vascular dilation of the portal area and the sinusoids, with bile duct hyperplasia extending progressively and the thickening of interlobular connective tissue septa with a generalized perilobular connective tissue reaction, which did not seem to alter the internal structure of the lobule, which showed histologically normal hepatocytes. The fibrous reaction may be the first stage in chronic hepatopathy. Further long-term studies are required in this model.     

慢性重型肝炎肝移植的手术时机

目的 探讨慢性重型肝炎肝移植的手术时机.方法 回顾性分析135例慢性重型肝炎病人的临床资料,应用终末期肝病模型(MELD)评估病人病情,比较病人入院时MELD值和接受治疗2周后△MELD值与病人3个月死亡率之间的关系.结果 死亡组病人入院时MELD值为37±7,存活组为26±5,两组间差异有显著统计学意义(P＜0.01);死亡组病人接受治疗2周后△MELD值为1.6±2.2,存活组为-1±5,两组间差异有显著统计学意义(P＜0.01).病人入院时MELD值和接受治疗2周后△MELD值预测慢性重型肝炎病人3个月内死亡率的c-statistic分别为0.903和0.760.如MELD值＜25,病人3个月后死亡率为1.8%;25≤MELD值≤30,死亡率为7.4%;30＜MELD值＜35,死亡率为42.9%;MELD值≥35,死亡率为80.6%,各组间死亡率比较差异有非常显著的统计学意义(P＜0.01);△MELD分值＞0组和≤0组的死亡率分别为51%和13.1%,两组间死亡率有非常显著的差异(P＜0.01).结论 MELD分值和△MELD分值与慢性重型肝炎病人的死亡率呈正相关,MELD能较准确地预测慢性重型肝炎病人的病情转归,临床医生可以结合病人入院时的MELD分值和接受治疗后的△MELD分值来决定慢性重型肝炎病人中转肝移植的手术时机,MELD值≥35时应该行肝移植治疗.     

门静脉动脉化在肝脏外科的应用

门静脉动脉化是一种为防止肝脏缺血导致的肝损害而将动脉血灌注入门静脉的方法.本文就其在肝移植、肝门部肿瘤和门脉高压症外科治疗、急性肝功能衰竭治疗中的临床应用情况及存在的问题做一综述.     

Auxiliary liver transplantation with portal arterialization in the rat: description of a new model

In recent years, portal arterialization has been used in liver transplantation to increase the portal flow, as a solution for singular technical problems. We have developed a new auxiliary liver transplantation model in the rat with portal arterialization, so the native hepatic hilium remains untouched, consisting on a graft with a previous 70% hepatectomy. It is sited on the right renal bed, joining the infrahepatic inferior vena cava (IVC) of the graft with the recipient IVC. With an abdominal aortic graft, we connect the recipient aorta with the portal vein from the auxiliary liver. All the animals survived at the seventh day. No thrombosis was seen in any graft and an important rejection was observed in all the fields. We have developed a new experimental model of an auxiliary liver with portal arterialization, avoiding the utilisation of the native hepatic hilium, necessary for the possible recovering of the proper liver in the case of a reversible fulminant hepatitis.