Establishment of orthotopic liver transplantation model in pigs without veno-venous bypass / 中华器官移植杂志

Objective To summarize the experience of orthotopic liver transplantation in pigs without veno-venous bypass.Method In general,Bama miniature pigs were used as both the donors and the recipients.Suprahepatic inferior vena cava and portal vein anastomosis was performed with running prolene sutures.After completion of the portal vein anastomosis,the graft was reperfused.Infrahepatic inferior vena cava anastomosis and hepatic artery anastomosis were performed in a similar fashion.Finally,the common bile duct was reconstructed.Result For all of the transplant procedures,the average cold ischemic time was 356.3 ± 66.4 min and anhepatic time 22.5 ± 2.6 min,and the average operative time was 185.7 ± 24.8 min.During the anhepatic phase,the central venous pressure (CVP) and the mean arterial pressure (MAP) were significantly lower than those at baseline (P＜ 0.05).Heart rate (HR),on the other hand,was increased significantly during the anhepatic phase (P＜0.05).By the time the portal vein and the hepatic artery were reperfused,and CVP and MAP were gradually elevated,and HR gradually reduced.All receptors were successfully extubated and awake after surgeries.On the third postoperative day they began to eat.All receptors survived during the intraoperative period,and the survival rate was 93.8％ (15/16) on the fifth postoperative day.One receptor was died on the third postoperative day due to abdominal infection.Conclusion This model has satisfactory stability and reproducibility.Without using any vasoactive substances,to maintain the MAP beyond 50 mmHg in the anhepatic phase and the short anhepatic time are important to perform successful liver transplantation.

Transplante de fígado clínico sem desvio venovenoso / Clinical liver transplantation without venovenous bypass

INTRODUÇÃO: O problema da utilização do desvio venovenoso no transplante de fígado é um ponto de discussão e controvérsia entre anestesistas e cirurgiões transplantadores. Apesar de proporcionar ambiente hemometabólico estável durante a fase anepática o seu uso poderá levar a algumas complicações, inclusive fatais. OBJETIVO: Revisar a prática atual do uso do desvio venovenoso no transplante de fígado clínico, com suas vantagens e desvantagens. MÉTODO: Foi realizada ampla pesquisa na literatura, com especial atenção aos artigos publicados nos últimos 10 anos e indexados ao PubMed e Medline. Foram utilizados os seguintes descritores de forma cruzada: liver transplantation, venovenous bypass, conventional technique, classic technique. Entre os artigos encontrados foram considerados para análise os mais relevantes além dos considerados "clássicos" sobre o assunto. CONCLUSÃO: Transplante de fígado sem desvio venovenoso é técnica segura e rápida. Pode ser utilizada, com poucas exceções, sem acarretar complicações maiores nos pacientes com doença hepática.

INTRODUCTION: The use of a venovenous bypass in liver transplantation is a controversy source and discussion among anesthetists and transplant surgeons. Although it provides a stable hemodynamic state and metabolism during the anhepatic stage, venovenous bypass may lead to a number of complications, some of them with death. AIM: To review the current practice of using clinic venovenous bypass in liver transplantation, with its advantages and disadvantages. METHOD: A broad review of the literature was carried out, paying especial attention to articles published in the past ten years and indexed in PubMed and Medline. The following cross-referenced headings were used: liver transplantation, venovenous bypass, conventional technique, classic technique. The articles chosen for analysis were those of the greatest relevance and those considered "classics" in the subject. CONCLUSION: Liver transplantation without venovenous bypass is a safe and rapid technique. In most cases it can be used without giving rise to serious complications in patients with liver disease.

Does the Venovenous Bypass influence Coagulation Status in Living-Related Liver Transplantation? / 대한마취과학회지

BACKGORUND: Venovenous bypass (VVB) in liver transplantation has been used to decrease the acute hemodynamic and metabolic changes during anhepatic periods. But, the use of VVB in patients undergoing liver transplantation is still under debate concerning its relative risks and benefits. Therefore, the aim of this study was to examine the influences of VVB on the coagulation status and the amount of transfusion in living-related liver transplantation. METHODS: We conducted this retrospective study on 39 patients who underwent orthotopic living-related liver transplantation using the piggyback technique from March 2001 to April 2002. While 19 patients did not receive venovenous bypass, 20 patients received. We compared the two groups in terms of coagulation-related parameters (prothrombin time, activated partial thromboplastin time, platelet count, fibrinogen and thromboelastograph), the amount of transfusion during intraoperative and post-operative 1day. We also compared the incidences of post-reperfusion syndrome in the two groups. RESULTS: The group that underwent living-related liver transplantation with VVB required more packed red blood cell (p-RBC) transfusion than the other group without VVB from post-reperfusion untill the end of operation (P<0.05). This difference in the amount of p-RBC transfusion may be due to the blood remained in the VVB circuit at the termination of VVB. However, the two groups were similar in terms of coagulation-related parameters, the amount of other blood components, such as fresh frozen plasma, platelet concentrates, cryoprecipitate, total amount of transfusion during the 24 hours post- operatively, and the incidence of post-reperfusion syndrome. CONCLUSiONS: We conclude that the using of venovenous bypass in living-related liver transplantation did not influence coagulation status and the amount of transfusion perioperatively.

The changes of hemodynamics and electrolyte in orthotopic liver transplantation without venovenous bypass / 中国医师杂志

Objective To investigate the clinical significance of the changes of hemodynamics and electrolyte during orthotopc liver transplantation.Methods We studied 9 patients undergoing elective orthotopic liver transplantation without venovenous bypass,drew out arterial blood for monitoring arterial blood gas tensions,Na~+,K~+,Ca~(2+) and observed changes in hemodynamics and electrolyte.Results In most patients,arterial pressure significantly decreased at the prophase of the anhepatic phase,and tended to normal range in other phases.The concentration of calcium maintained a low-level during the whole surgery.During the prophases of the anhepatic phase and neo-hepatic phase,there was a light hyperkalemia,and the concentration of natrium slightly increased since 30 minutes after the anhepatic phase and neohepatic phase,but insensibly exceeded normal range.With resuming of the stability of hemodynamics,these changes had followed.Conclusion We shoud give our attention to correct the occurrence of the hypocalcemia during the forepart of the anhepatic phase and neo hepatic phase,and care for the hyperkalemia 5 minutes after the block of liver blood purveyance and revascularization of liver.The lock of body capability shoud be recruit duly according to the lose of blood and hemacytometer changes.In order to prevent serious academia and maintain the stability of hemodynamics and electrolyte,vasoconstrictor shoud be used carefully during the anhepatic phase.

Hepatectomia total com preservação da veia cava inferior: "piggy-back" experimental em cães

During the recipient hepatectomy in liver transplantation, preservation of the retrohepatic segment of the inferior vena cava has several advantages: it decreases warm ischemia time by eliminating the infrahepatic caval anastomosis, eliminates the need for venovenous bypass and eases retransplantation. Removal of the liver of the dog without sacrificing the inferior vena cava has been considered impossible because of the intrahepatic course of the vena cava at the sites of entry of the hepatic veins. The following report reviews the history of the piggyback method, and discuss about the feasibility of the total removal of the liver without injury to the vena cava in the dog.

No transplante de fígado, a preservação do segmento retro-hepático da veia cava durante a hepatectomia do receptor apresenta uma série de vantagens: diminuição do tempo de isquemia quente por eliminar a anastomose da veia cava infra-hepática, redução da necessidade da utilização de derivações veno-venosas e simplificação da cirurgia do re-transplante hepático. Em cães, os lobos hepáticos lateral direito e caudado são caprichosamente atravessados pela veia cava inferior, dificultando a completa "esqueletização" do vaso. No presente trabalho, os autores revisam a singular história do método do "piggy-back" experimental e clínico, e discutem a técnica da cirurgia em cães.

Treatment of Retrohepatic Caval Injury using Total Hepatic Vascular Isolation and Venovenous Bypass / 한국간담췌외과학회지

Retrohepatic caval injuries are a difficult problem to surgeons as its mortality approaching 50~80%. Several bypass techniques was advocated to reduce operative bleeding and to improve the prognosis of the traumatized patients. We successfully managed a case of retro hepatic caval injury using venovenous bypass and total hepatic vascular isolation. A 28 year old female patients was admitted to Cheju Medical Center injured in a traffic accident. At exploration, a retrohepatic caval injury was suspected. So patient was emergently transferred to Seoul National University Hospital, after gauze packing. On arrival, vital signs were stable. Reexploration was undertaken. There was gush out of blood from retrohepatic space. After clamping suprahepatic and infrahepatic vena cava, venovenous bypass was introduced to left axillary vein and left femoral vein using Biomedicus pump. Systemic heparinization was not used. Avulsion between vena cava and common trunk of left and middle hepatic veins was repaired and left hepatectomy was done. Gauze packing was done due to ongoing oozing by coagulopathy from massive transfusion. Total venovenous bypass time was 30 min. On 10th operative day, reexploration was undertaken to assure hemostasis and to remove packed gauze. On 54th postoperative day patient discharged without any morbidity.

Effect of anatomical and physiological features on orthotopic liver transplantation in pigs / 中国普通外科杂志

Objective To study the setting up a model of orthotopic liver transplantation (OLT) in pigs. Methods In pigs, OLT were performed based on the porcine anatomical and physiological features, and the extracorporeal veno venous bypass was established during the anhepatice stage. Results Fourteen pigs(87.5%) of 16 OLT survived after the operation, and the haemodynamics?serum biochemical parameters and core temperature were maintained in the normal value during OLT. Conclusions Extracorporeal venovenous bypass and perfect surgical techniques based on the anatomical and physiological features are the key to successful OLT in pigs.

The Effect of Venovenous Extracorporeal Lung Assist on the Oxygenation of Mixed Venous Blood : Comparison of venovenous bypass using a dulble lumen tube with that using two catheters / 대한마취과학회지

At the beginning of 1980's, respiratory support by extracorporeal circulation using a membrane oxygenator attracted medical attention again because it could provide the diseased lung with rest. The extracorporeal respiratory support has been called extracorporeal membrane oxygenation (ECMO), extracorporeal CO2, removal (ECCO2R) or extracorporeal lung assist (ECLA). They are the terms used to describe prolonged extracorporeal venoarterial (VA) or venovenous (VV) bypass via extrathoracic cannulation in patients with acute, reversible cardiac or respiratory failure refractory to conventional medical or pharmacologic management. Usually VV bypass is maintained by cannulating the superior vena cava through one major catheter and the inferior vena cava through another. To reduce the number of veins to be cannulated during VV bypass, a double lumen tube was designed. To compare VV ECLA using a double lumen tube with that using two catheters, we observed the changes of the PvO2 (delta PvO2) as a parameter of extracor-poreal oxygenation. A process from ECLA off to ECLA on was performed thirty-three times on 7 mongrel dogs by VV ECLA using a double lumen tube (double lumen group, 16.7+/-1.9 kg, mean+/-standard deviation) and thirty-four times on 6 mongrel dogs by that using two catheters (two-way bypass, control group, 16.1+/-3.0 kg). In double lumen group, bypass flow rate was 52.3+/-15.1ml/kg/min and bypass ratio (bypass flow/cardiac outputX100) was 65.0+/-25.3%. During ECLA off, PvO2, was 43.3+/-6.7 torr and it was raised to 70.1+/-15.4 torr during ECLA on (p<0.001). delta PvO2 was 27.2+/-17.8 torr. In control group, bypass flow rate was 56.1+/-20.5 ml/kg/min and bypass ratio was 72.3+/-29%. During ECLA off, PvO2, was 39.4+/-7.8 torr and it was raised to 58.4+/-3.9 torr during ECLA on (P<0.001). delta PvO2 was 18.3+/-7.9 torr. delta PvO2, of double lumen group was higher than that of control group (p<0.001). The rise of delta PvO2, (y) following the increaae of bypass ratio (x) was y= -6.54+0.50x (r=0.71, P< 0.001) in double lumen group, and y=0.67+0.26x (r=0.88, P<0.001) in control group. It could be concluded that the rise of PvO2 was obtained more efficiently in double lumen group than in eontrol group (p<0.001). A double lumen tube may permit the simplicity of an operation and patient care as well as minimizing the bleeding during clinical ECLA.