Surgical anatomy applied to transperitoneal approaches of the abdominal aorta and visceral trunks. Dynamic article

Access to the abdominal aorta and its visceral trunks is possible through several approaches. Dissections of five cadavers performed during three National Surgical Anatomy courses applied to Aorta, Hepatobiliopancreatic and Digestive Surgery. Videos and pictures were taken throughout the dissections and showed different abdominal aorta approaches. Abdominal aorta and visceral trunks approaches: longitudinal inframesocolic access, supraceliac clamping, celiac trunk dissection, superior mesenteric artery approaches (retroperitoneal after Kocher menoeuvre, supramesocolic or inframesocolic), Cattell-Braasch manoeuvre and mattox manoeuvre: retrorenal and prerenal. Correct knowledge of the intraabdominal anatomy is necessary to perform all the abdominal aorta surgical approaches. Cadaveric dissection could help to achieve this objective. Cardiovascular and digestive surgeons need to know the possible strategies in order to choose the one which is best suited for each patient.

Surgical anatomy applied to transperitoneal approaches of the abdominal aorta and visceral trunks. Dynamic article

Access to the abdominal aorta and its visceral trunks is possible through several approaches. Dissections of five cadavers performed during three National Surgical Anatomy courses applied to Aorta, Hepatobiliopancreatic and Digestive Surgery. Videos and pictures were taken throughout the dissections and showed different abdominal aorta approaches. Abdominal aorta and visceral trunks approaches: longitudinal inframesocolic access, supraceliac clamping, celiac trunk dissection, superior mesenteric artery approaches (retroperitoneal after Kocher menoeuvre, supramesocolic or inframesocolic), Cattell-Braasch manoeuvre and mattox manoeuvre: retrorenal and prerenal. Correct knowledge of the intraabdominal anatomy is necessary to perform all the abdominal aorta surgical approaches. Cadaveric dissection could help to achieve this objective. Cardiovascular and digestive surgeons need to know the possible strategies in order to choose the one which is best suited for each patient.

Efficacy of interleukin 10 gene hydrofection in pig liver vascular isolated 'in vivo' by surgical procedure with interest in liver transplantation

Aim

Liver transplantation is the only curative strategy for final stage liver diseases. Despite the great advances achieved during the last 20 years, the recipient immune response after transplantation is not entirely controlled. This results in high rates of acute cell rejection and, approximately, 10% of early mortality. Therapeutic treatment could be improved by efficiently transfecting genes that encode natural immunosuppressant proteins, employing safe procedures that could be transferred to clinical setting. In this sense, interleukin 10 plays a central role in immune tolerance response by acting at different levels.

Methods

hIL10 gene was hydrofected by retrograde hydrodynamic injection in pig liver with complete vascular exclusion mediated by an ‘in vivo’ surgical procedure. Levels of IL10 DNA, RNA and protein were determined within liver tissue 1 and 10 days after the injection and, more frequently, also the interleukin-10 protein in peripheral blood.

Results

The procedure was safe for the animals and neither hemodynamic parameters nor liver function determinations showed relevant alterations. The hIL10 hydrofection in watertight liver mediated efficient gene transfer and this was transcribed and translated to protein, achieving up to 110 pg/ml of IL10 in peripheral blood. This value is close to that considered able to reduce the activity of TNFα by half (IL10 IC₅₀ for TNFα = 124 pg/ml).

Conclusions

Results of this work suggest that IL10 liver hydrofection with vascular exclusion in vivo is a safe and transferable procedure that mediates plasma protein levels with potential clinical interest in immune modulation after transplantation.

Low RNA translation activit limits the efficacy of hydrodynamic gene transfer to pig liver in vivo

BACKGROUND

Hydrodynamic gene delivery has proved an efficient strategy for nonviral gene therapy in the murine liver but it has been less efficient in pigs. The reason for such inefficiency remains unclear. The present study used a surgical strategy to seal the whole pig liver in vivo.

METHODS

A solution of enhanced green fluorescent protein (eGFP) DNA was injected under two different venous injection conditions (anterograde and retrograde), employing flow rates of 10 and 20 ml/s in each case, with the aim of identifying the best gene transfer conditions. The gene delivery and information decoding steps were evaluated by measuring the eGFP DNA, mRNA and protein copy number 24 h after transfection. In addition, gold nanoparticles (diameters of 4 and 15 nm) were retrogradely injected (10 ml/s) to observe, by electron microscopy, the ability of the particle to access the hepatocyte.

RESULTS

The gene delivery level was higher with anterograde injection, whereas the efficacy of gene expression was better with retrograde injection, suggesting differences in the decoding processes. Thus, retrograde injection mediates gene transcription (mRNA copy/cell) equivalent to that of intermediate expression proteins but the mRNA translation was lower than that of rare proteins. Electron microscopy showed that nanoparticles within the hepatocyte were almost exclusively 4 nm in diameter.

CONCLUSIONS

The results suggest that the low activity of mRNA translation limits the final efficacy of the gene transfer procedure. On the other hand, the gold nanoparticles study suggests that elongated DNA conformation could offer advantages in that the access of 15-nm particles is very limited.

New alternatives to the treatment of acute liver failure

INTRODUCTION

Acute-on-chronic liver failure (ACLF) is defined as an acute deterioration of a chronic liver disease. The most effective treatment in these patients is orthotopic liver transplantation (OLT), which is highly limited by the donor shortage. The aim of this study was to increase the usefulness of hepatocyte transplantation (HT) as a bridge or alternative to OLT.

METHODS

During the last 2 years, we have performed HT in 3 patients with ACLF. The diagnosis was graft cirrhosis due to hepatitis C virus in 2 of them, who were already included on waiting lists for retransplantation, and the third, unknown alcoholic cirrhosis.

RESULTS

After the first HT infusion, we observed an improvement in the clinical condition in all patients, hyperammonemia, and a partial correction of the degree of encephalopathy; 1 patient was retransplanted 6 days after the first HT.

DISCUSSION

The main indications for HT are inborn errors of metabolism in children. Other indications especially in adults, are acute liver failure, ACLF in patients with end-stage-liver disease who are a waiting OLT, and acute liver failure after an hepatectomy. HT may be a new treatment to improve the clinical condition in patients awaiting OLT.

Lessons learned from anatomic variants of the hepatic artery in 1,081 transplanted livers

The aim of this study is to contribute our experience to the knowledge of the anatomic variations of the hepatic arterial supply. The surgical anatomy of the extrahepatic arterial vascularization was investigated prospectively in 1,081 donor cadaveric livers, transplanted at La Fe University Hospital from January 1991 to August 2004. The vascular anatomy of the hepatic grafts was classified according to Michels description (Am J Surg 1966;112:337-347) plus 2 variations. Anatomical variants of the classical pattern were detected in 30% of the livers (n=320). The most common variant was a replaced left artery arising from the left gastric artery (9.7%) followed by a replaced right hepatic artery arising from the superior mesenteric artery (7.8%). In conclusion, the information about the different hepatic arterial patterns can help in reducing the risks of iatrogenic complications, which in turn may result in better outcomes not only following surgical interventions but also in the context of radiological treatments.

Influence of preservation solution on the isolation and culture of human hepatocytes from liver grafts

A major problem for the isolation and transplantation of hepatocytes is the lack of resources for obtaining viable hepatocytes. Improving this situation would enhance hepatic cell transplantation programs. Our objective was to evaluate the influence of the preservation solutions used during organ retrieval on the quality of hepatocytes isolated from liver tissue. We compared the results of the collagenase perfusion technique for isolation of hepatocytes in human livers flushed with University of Wisconsin (UW) and Celsior preservation solutions. Yield (number of viable cells per gram of tissue), cellular viability, efficiency of cells to attach to culture plates and form a monolayer, and drug metabolizing competence of the hepatocytes were measured. Successful isolation was achieved in 63% of the procedures using the UW solution and 100% of the procedures using the Celsior solution. In the UW group, significantly lower cell viability (38 +/- 41% vs. 79 +/- 14%, p < 0.05), yield of cells (4.0 +/- 5.2 x 10(6) vs. 8.2 +/- 5.6 x 10(6) cells/g, p < 0.05), and protein content at 24 h of culture (0.6 +/- 0.6 vs. 1.2 +/- 0.3 mg protein per plate, p < 0.05) than in Celsior solution were found. However, similar values of P450 activities were found in both groups. The more successful isolation, better yield, and higher cell viability obtained from human liver grafts preserved in Celsior solution, in comparison to UW solution, suggest Celsior solution as the most appropriate for preserving cadaveric hepatic tissue to be used for hepatocyte harvesting.

Functionality of cultured human hepatocytes from elective samples, cadaveric grafts and hepatectomies

The major possible sources of human liver for hepatocyte isolation are elective liver biopsies, cadaveric liver grafts and therapeutic liver resections. The suitability in terms of metabolic-competent hepatocyte cultures and risk/benefit of these resources has been comparatively studied. To this end, viability of isolated hepatocytes, yield of isolation procedure, hepatocyte survival during culture and CYP activities were the parameters analysed. The best results were found in hepatocytes prepared from elective biopsies, whereas a marked reduction in viability and functional competence was seen in hepatocytes from hepatectomy samples. Metabolic differences were observed in total CYP oxidative metabolism (7-ethoxycoumarin O-deethylation, total testosterone hydroxylation), as well as in CYP3A4, CYP2C9 or CYP2C19 activities (testosterone oxidations at 6beta-, 16beta- and 17-positions, respectively). Vascular control during the hepatectomy procedure influenced hepatocyte functionality: higher CYP activities were found in hepatocytes isolated from samples obtained under non-ischemic conditions or continuous vascular clamping than in those obtained under intermittent vascular clamping. In addition to cellular functionality, other criteria such as sample availability or ethical aspects should be considered. Elective biopsies have low, but not absent, surgical risk. However, the better functionality and the higher accessibility of elective liver samples in comparison to the other groups suggest this source of liver tissue as the most appropriate for cell harvesting purposes.

Hepatocellular carcinoma: Can it be considered a controversial indication for liver transplantation in centers with high rates of hepatitis C?

Hepatocellular carcinoma (HCC) is still considered a controversial indication for liver transplantation (LT), mainly because of long waiting times and underlying viral cirrhosis. The goal was to evaluate the outcome of LT in 104 patients with HCC and cirrhosis, mainly hepatitis C virus (HCV)-related, in a center with a short waiting time (median, 105 days). Four groups were formed according to the HCC and HCV status: HCV positive with HCC (group 1, n = 81), HCV negative with HCC (group 2, n = 23), HCV positive without HCC (group 3, n = 200), and HCV negative without HCC (group 4, n = 207). Predictive factors of tumor recurrence were demographics, tumor related (size or number of nodules, capsule, bilobar involvement, vascular or lymphatic invasion, clinical and pathologic TNM staging, pre-LT percutaneous ultrasound-guided ethanol injection or transarterial chemoembolization, alpha-fetoprotein levels), donor and surgery related, and year of transplantation. The same variables and "tumor recurrence (yes/no)" were applied to evaluate the effect on survival. The median follow up was 29 months (range, 0 to 104 months). Patient survival was 70% at 1 year and 59% at 5 years for group 1, 87% at 1 year and 77% at 5 years for group 2, 81% at 1 year and 64% at 5 years for group 3, and 88% at 1 year and 77% at 5 years for group 4 (P =.013). Survival was significantly lower in patients with HCC than in those without (74% and 63% versus 85% and 70%, at 1 and 5 years, respectively; P =.05). The causes of death in those with and without HCC were tumor recurrence (24%) and recurrent HCV (8%) versus sepsis (34%) and recurrent HCV (14%). HCC recurrence occurred in 12 patients (11.5%) at a median of 14 months (range, 3 to 60 months) with a probability increasing from 8% at 1 year to 16% at 5 years. In patients with HCC, tumor recurrence was associated with vascular invasion (P =.0004) by multivariate analysis; variables predictive of survival were donor old age (P =.01), viral-related etiology (P =.02), and tumor recurrence (P =.001). Although LT still remains an adequate indication for HCC in centers with high prevalence of HCV infection and short waiting times, both tumor and HCV-related recurrent diseases hamper significantly the outcomes of these patients.

Contribution of donor age to the recent decrease in patient survival among HCV-infected liver transplant recipients

Recurrent hepatitis occurs in the majority of patients undergoing liver transplantation for hepatitis C virus (HCV) cirrhosis, with progression to cirrhosis in up to 30% after 5 years. Based on these data, a decrease in survival can be anticipated with prolonged follow-up. Furthermore, posttransplantation HCV-fibrosis progression has been shown in recent years to increase. Our aims were (1) to describe the natural history of HCV-infected recipients, particularly to determine whether survival has decreased in recent years; (2) to compare this outcome with that observed in non-HCV-infected cirrhosis controls; and (3) to determine the factors associated with disease severity and survival. Among 522 cirrhotic patients undergoing transplantation between 1991 and 2000, 283 (54%) were infected with HCV. Yearly biopsies were performed in these recipients and at 1 and 5 years in the remainder. With similar follow-up, the percentage of deaths in the HCV(+) group was significantly higher than in the HCV- group (37% vs. 22%, P <.001), and patient survival was lower (77%, 61%, 55% vs. 87%, 76%, 70% at 1, 5, and 7 years, respectively; P =.0001). Although survival has increased in the HCV- group in recent years, it has significantly decreased in HCV recipients (P <.0001). The main cause of death among the latter was decompensated graft cirrhosis (n = 23/105, 22%), whereas that of HCV- patients was infections (n = 10/52, 19%). Reasons for the recent worse outcome in HCV+ recipients include the increased donor age and stronger immunosuppression. In conclusion, patient survival is lower among HCV+ recipients than among HCV- ones and has been decreasing in recent years. The aging of donors is a major contributor to this worse outcome.

[A new case of hepatic adenomatosis treated with orthotopic liver transplantation]

Hepatic adenomatosis is a rare disease with multiple hepatic adenomas (10 or more), not associated with an history of oral contraceptive use or anabolic steroids use or with glycogen storage disease. A new case is reported in a 23 year-old woman who consulted for an abdominal mass and who had more than 50 adenomas of the liver. The suspicion of malignant transformation by the elevation of the alpha-foetoprotein, and the diffuse affectation of the liver, with minimum free parenchyma, suggested to carry out an orthotopic liver transplantation. The definitive histological examination of the surgical specimen confirmed the existence of local areas of hepatocellular carcinoma.

[Isolated hepatic transplant in patient with cystic fibrosis]

Cystic fibrosis (CF) is a recessive autosomic disease with multiorgan, although predominantly pancreatic and pulmonary, involvement. Liver involvement is infrequent in children under the age of 5 years, but increases progressively with time. It is characterized by the development of focal biliary cirrhosis with eventual appearance of portal hypertension. During the last few years the more effective control of the pulmonary complications, which are the main cause of mortality, has led to an increase in the survival of these patients and thus the number of patients with CF and liver involvement is greater every day. In these cases, the prognosis is bad and most patients die in 4 to 5 years. Isolated liver transplantation is a recently proposed alternative for patients who have developed liver cirrhosis but who maintain acceptable pulmonary function. The case of a 14-years-old patient in whom liver transplantation was performed with good results after 8 months of follow-up is presented. Improvement in the nutritive state and pulmonary function was observed.