Competition between native liver and graft in auxiliary liver transplantation in a rat model

The competition between the native and the grafted liver in heterotopic auxiliary liver transplantation (HALT) with portal vein arterialization (PVA) was investigated in a rat model. The experimental groups were: HALT with flow-regulated PVA and 70% resection of a native liver and graft (n = 32; group I) versus 70% liver resection (n = 32; group II). After HALT, the weight of the native liver increased until the sixth postoperative week (431% +/- 55% of the intraoperative weight), whereas, the graft weight was only 76% +/- 31% of the intraoperative weight at this time. In group II, liver weight increased continuously to 529% +/- 30% of the intraoperative weight after 6 weeks. On postoperative day 2, there was significantly increased proliferative hepatocellular activity in all groups. This was highest in the resected livers of group II, followed by the native livers of group I, and the grafts of group I (301 +/- 126 vs 262 +/- 97 vs 216 +/- 31 Ki-67-positive hepatocytes/10 visual fields). However, the differences between the groups were not significant. With regard to hepatocellular apoptosis, the livers were similar among all groups and at all time points, M30-positive hepatocyte counts were 相似文献   

Auxiliary liver transplantation: how to improve regeneration of the native liver by surgery

The technical factors which could influence regeneration of the native liver (NL) in auxiliary liver transplantation (ALT) for fulminant hepatic failure (FHF) are not well known. We studied NL regeneration according to the location of graft anastomosis in the recipient's portal system (superior mesenteric vein versus portal vein), and graft weight (50 % reduced-size versus full-size graft) in a rat model of ALT with 80 % reduction of the NL, and graft arterialization. NL regeneration was significantly more obvious when the graft was anastomosed on the recipient's superior mesenteric vein, thus establishing venous flow to the NL from the pancreas, the spleen, and the stomach, and when a full-size graft was used. The influence of portal venous flow on NL regeneration, assessed by [³H]-thymidine incorporation, was measurable as early as day 2. Both technical variables in combination resulted in significantly greater regeneration (ratio weight of NL/body weight at day 30: 2.32 ± 0.68 % versus 1.21 ± 0.63 % respectively, P = 0.02). Early preservation of portal flow to the NL is advisable to maximize NL regeneration in ALT. In any case, this regeneration is not impeded by the use of large auxiliary grafts. Received: 11 February 1999 Received after revision: 29 July 1999 Accepted: 1 September 1999     

Portal blood flow and liver regeneration in auxiliary partial orthotopic liver transplantation in a canine model

Functional competition has been shown to lead to a detrimental outcome in auxiliary liver transplantation. We evaluated the interaction in auxiliary partial orthotopic liver transplantation between the native liver and the graft in terms of portal flow and regeneration. The need for diversion of the portal flow to the graft was also assessed. Reduced-size liver grafts were transplanted orthotopically after partial hepatectomy in beagles. There were two groups: the preserved group, where portal inflow to the native liver was preserved, and the ligated group, where it was interrupted. Portal flow was measured serially and liver regeneration was evaluated on postoperative day 5. Functional competition was not observed in the preserved group. On the other hand, ligation of the native liver portal vein had no obviously detrimental effects on the remnant native liver. This leads to the conclusion that the portal vein to the native liver can be safely ligated to prevent functional competition.     

Auxiliary partial orthotopic liver transplantation: treatment of acute liver failure in a new rat model

BACKGROUND AND AIMS: Liver regeneration and functional interaction between native liver and graft after auxiliary partial orthotopic liver transplantation (APOLT) are not entirely understood and, therefore, require an experimental model simulating the clinical features of acute liver failure (ALF) and the surgical technique of APOLT. MATERIALS AND METHODS: ALF was induced by subtotal hepatectomy in 50 Lewis rats (200-250 g). Sham operation (I), ALF without treatment (II), ALF with portocaval shunt for decreasing blood flow of the remnant liver (III), and ALF treated by APOLT (IV) were performed. The auxiliary graft represented a left donor liver lobe which was orthotopically implanted using a microsurgical technique including reconstruction of the graft artery and internal biliary drainage. Operative outcomes, serum chemistry and histopathological findings were examined up to the 14th day. RESULTS: ALF without treatment (groups II and III) led to a small droplet fatty degeneration in the hepatocytes and a significant increase of liver parameters until the death of the animals within the first two postoperative days ( P<0.05). After APOLT (group IV), 80% of the animals survived up to the 14th day, revealing significantly decreased liver parameters ( P<0.05), a well-perfused graft and an up to five times increased native liver size with normal architecture. CONCLUSION: This new rat model simulates the clinical features of an ALF treated by APOLT and is especially interesting for further basic research on the interaction between native liver and auxiliary graft after APOLT.     

Directing portal flow is essential for graft survival in auxiliary partial heterotopic liver transplantation in the dog.

BACKGROUND/PURPOSE: Auxiliary liver transplantation is an attractive alternative for orthotopic liver transplantation in patients with certain inborn errors of metabolism of the liver in which complete resection of the liver is unnecessary or even contraindicated. Because in these diseases portal hypertension is mostly absent, finding a balance in portal blood distribution between native liver and graft is complicated. The objective of this study was to investigate requirements for long-term (180 days) graft survival in auxiliary partial heterotopic liver transplantation (APHLT) in a dog model. METHODS: A metabolic defect was corrected in 26 dalmation dogs with a 60% beagle heterotopic auxiliary liver graft. Four groups of different portal inflow were studied. In the ligation group the portal vein to the host liver was ligated. In the split-flow group graft and host liver received separate portal inflow. In the banding group the distribution of the portal flow was regulated with an adjustable strapband and in the free-flow group the portal blood was allowed to flow randomly to host or graft liver. RESULTS: Metabolic correction increased in all groups after transplantation from 0.19 +/- 0.02 to 0.70 +/- 0.05 (P< .0001) but remained significantly better in the ligation and split-flow groups (graft survival, 135 +/- 27 and 144 +/- 31 days). In the banding group metabolic correction decreased significantly after 70 days, and although the grafts kept some function for 155 +/- 14 days, in 4 of 6 dogs portal thrombosis was found. In the free-flow group, competition for the portal blood led to reduced correction within 12 days and total loss of function in 96 +/- 14 days. Graft function also was assessed with technetium (Tc) 99m dimethyl-iminodiacetic acid uptake. A good linear association between HIDA uptake and metabolic correction was observed (r = 0.74; P < .0005). Grafts that contributed more than 15% to the total uptake of HIDA showed biochemical correction. This indicates a critical graft mass of about 15% to 20% of the hepatocyte volume to correct this metabolic defect. CONCLUSION: Auxiliary partial heterotopic liver transplantation can be a valuable alternative treatment for inborn errors of hepatic metabolism if the native liver and the graft receive separate portal blood inflow.     

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     

Improved microcirculation of a liver graft by controlled portal vein arterialization

BACKGROUND: The clinical results of portal vein arterialization (PVA) in liver transplantation are controversial without a standardized portal flow regulation. The aim of these experiments was to perform a flow-regulated PVA in liver transplantation, to examine the microcirculation and early graft function after heterotopic auxiliary liver transplantation (HALT) with flow-regulated PVA, and to compare this technique with HALT with porto-portal anastomosis. Using the recently developed orthogonal polarization spectral (OPS) imaging, for the first time the microcirculation of liver grafts with PVA was visualized. MATERIALS AND METHODS: HALT was performed in Lewis rats. The portal vein was either completely arterialized via the right renal artery in a standardized splint-technique (Group I, n = 8) or anastomosed end-to-end to the recipient's portal vein (Group II, n = 8). RESULTS: After reperfusion, the average blood flow in the portal vein was within the normal range in Group I (1.7 +/- 0.4 ml/min/g liver weight) and significantly higher than in Group II (1.2 +/- 0.2 ml/min/g liver weight). The functional sinusoidal density in Group I (335 +/- 48/microm) was significantly higher than in Group II (232 +/- 58/microm), whereas the diameter of the sinusoids and the postsinusoidal venules yielded no significant differences between both groups. The bile production was comparable (27 +/- 8 versus 29 +/- 11 microl/h/g liver weight). CONCLUSIONS: In our experiments it was possible to achieve an adequate flow regulation in the arterialized portal vein with good results concerning microcirculation and early graft function. We recommend that further investigations on liver transplantation with PVA should be performed with portal flow regulation, before PVA is employed in clinical transplantation.     

Portal vein reconstruction in pediatric liver transplantation from living donors.

OBJECTIVE: The authors analyze the surgical pattern and the underlying rationale for the use of different types of portal vein reconstruction in 110 pediatric patients who underwent partial liver transplantation from living parental donors. SUMMARY BACKGROUND DATA: In partial liver transplantation, standard end-to-end portal vein anastomosis is often difficult because of either size mismatch between the graft and the recipient portal vein or impaired vein quality of the recipient. Alternative surgical anastomosis techniques are necessary. METHODS: In 110 patients age 3 months to 17 years, four different types of portal vein reconstruction were performed. The portal vein of the liver graft was anastomosed end to end (type I); to the branch patch of the left and right portal vein of the recipient (type II); to the confluence of the recipient superior mesenteric vein and the splenic vein (type III); and to a vein graft interposed between the confluence and the liver graft (type IV). Reconstruction patterns were evaluated by their frequency of use among different age groups of recipients, postoperative portal vein blood flow, and postoperative complication rate. RESULTS: The portal vein of the liver graft was anastomosed by reconstruction type I in 32%, II in 24%, III in 14%, and IV 29% of the cases. In children <1 year of age, type I could be performed in only 17% of the cases, whereas 37% received type IV reconstruction. Postoperative Doppler ultrasound (mL/min/100 g liver) showed significantly (p < 0.05) lower portal blood flow after type II (76.6 +/- 8.4) versus type I (110 +/- 14.3), type III (88 +/- 18), and type IV (105 +/- 19.5). Portal vein thrombosis occurred in two cases after type II and in one case after type IV anastomosis. Portal stenosis was encountered in one case after type I reconstruction. Pathologic changes of the recipient native portal vein were found in 27 of 35 investigated cases. CONCLUSION: In living related partial liver transplantation, portal vein anastomosis to the confluence with or without the use of vein grafts is the optimal alternative to end-to-end reconstruction, especially in small children.     

The interrelationship between portal and arterial blood flow after adult to adult living donor liver transplantation

BACKGROUND: When adults are transplanted with segmental grafts, disparity between the size of the graft and the native organ is almost universal. These grafts presumably still receive all of the native portal inflow despite a reduced vascular bed and dramatically elevated blood flow may result. The hemodynamic changes after segmental transplantation in adults have not yet been studied and their clinical significance is unknown. METHODS: Portal venous and hepatic arterial blood flow were measured intraoperatively in right lobe liver donors and recipients with electromagnetic flow probes. Postoperative evolution was monitored in recipients with ultrasonography. RESULTS: Portal flow to the right lobe ranged from 601 to 1,102 ml/min before resection and from 1,257 to 2,362 ml/min after transplantation. There was a statistically significant linear correlation between the change in portal flow and graft to recipient body weight ratio. Arterial blood flow ranged from 213 to 460 ml/min before resection and from 60 to 300 ml/min after transplantation. Preoperative portal peak systolic velocity was uniformly around 10 cm/sec. Values on postoperative day 1 were increased to 30 cm/sec in recipients of cadaveric organs, to 50 cm/sec in recipients of organs with graft to recipient body weight ratios of more than 1.2%, and to 115 cm/sec in recipients of organs with ratios less than 0.9%. A decreasing tendency was universally observed. Arterial systolic velocity was inversely related to portal systolic velocity. Neither graft dysfunction nor vascular complications occurred. CONCLUSIONS: The hemodynamic pattern after right lobe transplantation is predictable and intraoperative measurements and ultrasonography are useful for monitoring. The size of the graft influences the magnitude of the hemodynamic changes.     

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.     

Hepatic microcirculatory disturbances due to portal vein clamping in the orthotopic rat liver transplantation model

Most modifications and applications of the orthotopic rat liver transplantation (ORLT) model require clamping of the portal vein, thus leading to ischemia of the gut. The purpose of this study was to evaluate the effect of portal vein clamping during ORLT on hepatic microcirculation and leukocyte--endothelial interaction by intravital fluorescence microscopy. ORLT were performed following 1 hr of cold storage in EuroCollins solution without (standard group) and with insertion of a portojugular shunt (shunt group) to minimize intestinal ischemia. ORLT induced reduction of perfused sinusoids (83%) and velocity of leukocytes (311 +/- 4.5 microns/sec; mean +/- SEM) compared with nontransplanted controls (99% and 417 +/- 4.9 microns/sec). Portojugular shunt during ORLT improved hepatic microvascular perfusion (89% and 355 +/- 3.4 microns/sec; P less than 0.05). Furthermore, percentage of permanent and temporary adherent leukocytes decreased significantly when a portosystemic shunt was applied (from 33.5 +/- 1% to 22.1 +/- 1% and 19.7 +/- 1.2% to 14.0 +/- 0.9%; P less than 0.05). The results of the study reveal that intestinal congestion and reperfusion results in a rise in leukocyte adhesion to the sinusoidal wall and in disturbances of the hepatic microcirculation. It seems likely that increased endotoxin concentrations in the portal vein induce an activation of hepatic macrophages that subsequently cause release of chemoattractant mediators. In conclusion, side effects of intestinal ischemia during experimental liver transplantation surgery on liver function due to release of chemoattractant mediators should be considered when experimental data are transferred to clinical settings.     

Portal flow diversion is essential for graft survival in canine auxiliary partial orthotopic liver transplantation

After auxiliary partial orthotopic liver transplantation for inborn errors of metabolism, finding a balance in portal blood flow distribution between native liver and graft is complicated. We investigated the correction of hypoallantoinuria in the Dalmatian dog with a reduced-size Beagle orthotopic auxiliary liver graft, depending on intra-operative intervention in the portal flow. There were three groups: a ligation group, where the host portal vein was tied off, a free-flow group with random flow to both livers and a banding group, where the host portal vein was banded with an adjustable strapband. Metabolic correction was initially seen in all groups, but ligation led to portal hypertension and early mortality. In the free-flow group, correction was lost after 7 days, while banding preserved correction until 6 weeks. We conclude that acute ligation can lead to portal hypertension and free-flow leads to hypoperfusion and early loss of metabolic correction. Banding divided the portal blood flow between host liver and graft and prolonged metabolic correction.     

可量化的受体门静脉干预调节猪辅助性部分肝移植两肝门静脉血流竞争

目的 观察不同程度的受体肝门静脉缩窄对猪辅助性部分肝移植(APLT)受体肝和移植肝门静脉血流竞争的防治作用,探讨一种可量化的受体肝门静脉干预标准.方法 32头健康幼猪按体重相近原则配对,取右半肝作为供肝,切除受体肝左叶,共行16次APLT.根据移植后受体门静脉缩窄程度,将其分为4组:对照组(n=5,门静脉未行处理),缩窄1/4组(n=4,受体门静脉宽度缩窄1/4),缩窄1/3组(n=4,缩窄1/3)和结扎组(n=3,门静脉结扎).定期观察各组受体肝和移植肝的体积大小、血流状况及组织结构的变化.结果 术中电解质变化各组基本相似,血流动力学变化以对照组和缩窄1/4组较为平稳;各组存活率和最长存活时间均以缩窄1/4组最优;门静脉造影示缩窄1/4组两肝之门静脉均得到较好显影,未见明显造影剂淤积和血管扩张;多普勒超声示各组移植肝门静脉依次增宽,流速分别为0.220、0.293、0.336和0.400 m/s,受体门静脉流速分别为0.275、0.294、0.328和0 m/s;两肝体积、充盈度和包膜紧张度以缩窄1/4组最为适中,坏死程度亦以缩窄1/4组最轻.结论 在供受体体重相近且无明显肝硬化时,为防治APLT门静脉血流竞争,以受体门静脉宽度缩窄1/4较为适宜.     

A novel auxiliary partial orthotopic liver transplantation model in rats

BACKGROUND: Although auxiliary partial orthotopic liver transplantation (APOLT) has become a well-accepted procedure recently, a practical experiment model in APOLT using small animals has yet to be developed. METHODS: Male Lewis rats were used for both donors and recipients. An auxiliary partial graft was obtained by ex vivo resection of the donor right and caudate lobes, and was transplanted orthotopically into the recipient after resection of the recipient medial and left hepatic lobes. Portal vein and hepatic duct reconstructions were by the cuff technique, and supra- and intrahepatic vena cava were sutured continuously. Operative outcomes, serum chemistry, liver tissue blood flow, angiographic and histopathological findings were then examined. Conventional orthotopic liver transplantation (OLT) procedures were also undertaken as a control. RESULTS: One-day, 1-week and 1-month survival rate of APOLT group was 100, 85 and 85%, respectively. AST in the APOLT group on the 1st postoperative day was significantly higher than in the OLT group. No significant differences were recognized in serum albumin and total bilirubin levels between the two groups. Although the portogram of an APOLT rat showed slight narrowing at the cuff anastomosis site, both the graft and the native liver were opacified similarly. The liver tissue blood flow on the 5th postoperative day in the native liver and the graft returned to as high as 95 and 74% of the values on laparotomy, respectively. Histological examinations of the auxiliary graft 1 month after transplantation showed mild ductular proliferation and mononuclear cell infiltration around the portal triads. CONCLUSION: This novel APOLT model in rats allows practical and reproducible results, and may be of value in the basic study of APOLT procedures.     

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.     

Portal hyperperfusion causes disturbance of microcirculation and increased rate of hepatocellular apoptosis: investigations in heterotopic rat liver transplantation with portal vein arterialization

Clinical results of portal vein arterialization (PVA) in liver transplantation are controversial. One reason for this is the lack of a standardized flow regulation. Our experiments in rats compared PVA with blood-flow regulation to PVA with hyperperfusion in heterotopic auxiliary liver transplantation (HALT). In group I (n = 19), the graft's portal vein was completely arterialized via the right renal artery in-stent technique, using a 0.3-mm stent, leading to a physiological average portal blood flow. In group II (n = 19), a 0.5-mm stent was used. In group II, the average portal blood flow after reperfusion was significantly elevated (group II: 6.4 +/- 1.5; group I: 1.7 +/- 0.4 mL/min/g of liver weight; P < .001). The sinusoidal diameter after reperfusion was significantly greater in group II (9.8 +/- 0.5 microm) than in group I (5.5 +/- 0.2 microm; P < .001). Red blood cell velocity in the dilated sinusoids was significantly lower in group II (171 +/- 18 microm/s) than in group I (252 +/- 13 microm/s). Stasis of erythrocytes occurred; consequently, the functional sinusoidal density was significantly reduced in group II (38 +/- 7%) compared with group I (50 +/- 3%; P < .01). Two hours after reperfusion of the portal vein, the number of apoptotic hepatocytes was significantly higher in group II than in group I (I: 0 +/- 0 vs II: 7 +/- 9 M30-positive hepatocytes/10 high-power fields). The 6-week survival rate was 9 of 11 in both groups. In group II, 6 of 9 grafts showed massive hepatocellular necroses after 6 weeks, whereas in group I, only 1 of 9 presented a slight hepatocellular necrosis. Finally, our results demonstrate negative effects of portal hyperperfusion in transplanted livers, which are correctable by adequate flow regulation.     

Auxiliary partial orthotopic liver transplantation in the treatment of acute liver failure: a case report

A successful experience with auxiliary partial orthotopic liver transplantation (APOLT) for acute liver failure is reported in a 29-year-old woman who experienced jaundice, generalized erythema for 7 days, and decreased mentation for 3 days. Two months prior, she suffered pulmonary tuberculosis, being currently treated with antituberculous medications, which caused the fulminant hepatic failure. We decided to perform APOLT based on two facts. The first was the possibility that the diseased native liver may recover sufficiently to withdraw the immunosuppressants. Second, the pulmonary tuberculosis may have been worsened by immunosuppression. We removed the extended lateral section of the recipient for the graft. The left hepatic vein of the extended left lateral graft was anastomosed to the left hepatic vein of the recipient. The left portal vein of the graft was anastomosed to the left portal vein of the recipient. The right portal vein of the recipient was left without any manipulation. A duct-to-duct anastomosis was performed. On postoperative day 3, antituberculous medications were started. On the postoperative day 37, she was discharged without any problems. On the postoperative day 120, she showed no event of rejection, and her pulmonary symptoms improved. We performed the operation without transection of the portal branch to the native liver, but no functional competition has been discovered.     

大鼠辅助性肝移植诱导免疫耐受模型的建立

目的利用PVG（TR-1^c）和DA（RT-1^a）大鼠分别为供受体，联合进行辅助性肝移植和异位心脏移植，建立大鼠辅助性肝移植诱导免疫耐受模型。方法辅助性肝移植采用重建门静脉法，异位心脏移植采用腹腔吻合法。结果同品系对照组和实验组动物及其移植心脏存活超过100d，而异品系对照组移植心脏只存活7d。结论在受体肝脏存在的情况下，辅助性供肝依然发挥其诱导耐受的效应。经长期观察，供肝无萎缩，耐受诱导效应持续存在，指示心脏搏动良好。因此，该模型在肝移植基础研究中具有实用价值。     

猪急性缺血性肝衰模型的建立和辅助性异位部分肝移植的作用

目的: 探讨急性缺血性肝衰模型的制备、辅助性异位部分肝移植的作用. 方法: 用家猪配对开展辅助性异位部分肝移植.分三组,A组:受体肝脏和肝动脉保持原状,其门静脉缩窄;供肝植入受体右肝下,仅建立门静脉血供,不建立动脉血供.B组:受体肝动脉结扎,其他手术内容与A组相同.C组:受体肝动脉结扎,供肝动脉和门静脉血供均建立,其他手术内容与A组相同.监测各组受体存活情况,肝功能和肝脏血流情况,病理及供肝胆汁分泌情况. 结果: A组、C组受体3 d以上成活率显著高于B组.A组、C组手术前后胆红素无显著改变,B组术后胆红素显著高于术前,术后第二天B组胆红素显著高于A组、C组.C组供肝胆汁分泌和血供良好,肝细胞存活并有活跃的代偿性增生;A组、B组供肝无或仅有少量胆汁分泌,肝细胞大片坏死. 结论: 受体肝动脉结扎、门静脉缩窄足以造成急性肝衰模型;保留受体肝脏动脉血供、减少门静脉血供对受体肝脏功能无严重影响;辅助性异位部分肝移植能取得良好的效果,足以纠正急性肝衰.     

Auxiliary partial orthotopic living donor liver transplantation as an aid for small-for-size grafts in larger recipients.

BACKGROUND: In countries where living donors are the only source of liver grafts, restrictions on graft size are a serious obstacle for the expansion of indications for adult recipients. To overcome this problem, auxiliary partial orthotopic liver transplants (APOLT*) was performed on the basis of the concept that the residual native liver would support the graft function until the graft had grown enough to function by itself. METHODS: APOLT as an aid for small-for-size (SFS) grafts was reviewed retrospectively to evaluate its feasibility. Between April 1995 and March 1998, 20 recipients underwent APOLT, which was indicated because of a SFS graft in 15 of them. The indication was based on the estimated graft/recipient's body weight ratio (GRWR). If the ratio was <0.8%, APOLT was performed. The other 5 patients had a graft with a GRWR >0.8% and underwent APOLT on the basis of the residual native liver supporting the graft function temporarily, 4 for supplementation of the defective enzyme in metabolic liver diseases and one for leaving the potential of the regeneration of the native liver in fulminant hepatic failure. The recipients who underwent APOLT because of a SFS graft were categorized as the SFS group, and the others were the second group. RESULTS: In the SFS group, the age of the recipients ranged from 13 to 48 (median 23). The original indications of this group were fulminant hepatic failure in 2 recipients, acute deterioration of chronic liver diseases in 3, Wilson's disease in 2, biliary atresia in 4, primary biliary cirrhosis in 3, and primary sclerosing cholangitis (PSC) in one. The actual GRWR ranged from 0.45 to 0.72 (median 0.55). The graft was implanted after resection of the left lateral segment of the native liver. Except in the first two patients, the portal vein to the residual native liver was completely transected so that all of the portal blood drained into the graft liver. This procedure was successful in 9 patients. The cause of death in the other 6 was mainly infection. The mortality rate among the recipients with signs of advanced liver failure, such as massive ascites or hepatic coma, was higher, even though APOLT was used to support the SFS graft. In the second group, in the other five recipients who underwent APOLT for other indications, one recipient with fulminant hepatic failure died of sepsis caused by the dehiscence of bilio-enteric anastomosis. CONCLUSIONS: APOLT as an aid for a SFS graft is technically viable. This procedure can thus expand the indication of living donor liver transplants for adult recipients when the native liver retains some functional capability to support the grafted liver during the immediate postoperative period.