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A Pascher

Publications and source records attributed to A Pascher.

At least 37 records · Page 2Linked to original sources

[Accuracy of the CT-estimated weight of the right hepatic lobe prior to living related liver donation (LRLD) for predicting the intraoperatively measured weight of the graft].

PURPOSE: Due to the shortage of cadaver donors, living related liver donation (LRLD) has emerged as an alternative to cadaver donation. The expected graft weight is one of the main determinants for donor selection. This study investigates the accuracy of preoperatively performed CT-volumetry to predict the actual weight of the right liver lobe graft. MATERIALS AND METHODS: In a prospective study the weight of the right hepatic lobe was calculated by volumetric analysis based on CT in 33 patients (21 females, 12 males, mean age 42.1 years, median age 41 years) prior to living related liver donation. Graft weight was calculated as the product of CT-based graft volume and 1.00 g/ml (the approximated density of healthy liver parenchyma). The calculated weight was compared with the intraoperatively measured weight of the harvested right hepatic lobe. The difference was used to determine a correction factor for estimating the actual graft weight. RESULTS: Based on the assumption of a parenchymal density of 1.00 g/ml, the preoperatively estimated graft weight (mean 980 g +/- 168 g) deviated +33 % from the intraoperatively measured right hepatic lobe weight (mean 749 g +/- 170 g). By reducing the preoperatively predicted weight of the right hepatic lobe with a correction factor of 0.75, the actual graft weight can be calculated. CONCLUSION: Preoperative estimation of the weight of the right hepatic lobe based on CT of living related liver donors predicts the weight of the right lobe graft with sufficient accuracy by applying a single correction factor. Intraoperative fluid loss (i.e., blood, bile) from the harvested liver as well as variations in parenchymal density may contribute to the observed preoperative overestimation of the actual graft volume by CT-based volumetry.

Adult↗

[Small bowel transplantation - current status and initial results].

During the last years, clinical small bowel transplantation has significantly improved. This is especially true for isolated small bowel transplantation with success rates of 80 % 1-year patient survival. Currently, approximately 100 small bowel transplantations are performed per year worldwide. In Germany, small bowel transplantation is still rare, because of the high risk for the development of acute rejection and rejection-associated complications. This includes peritonitis and sepsis as well as over-immunosuppression-associated infections. Due to improvements in immunosuppression, the incidence of acute rejection decreased from about 85 % below 25 %. Half of the patients will receive a combined liver-small bowel graft due to TPN (total parenteral nutrition)-associated liver cirrhosis. Although the combined procedure has immunological advantages, complication rates are high and patient survival is significantly lower (ca. 50 % at 1 year). Next to bacterial, fungal, and atypic infections, which are frequently associated with rejection and other complications, CMV and EBV infections are of significant interest. This is of special importance for EBV infections, since all PTLD (lymphoproliferative disease) after small bowel transplantation are EBV-associated so far. Viral infections should be monitored and preemptive therapy using ganciclovir or foscavir will be initiated. Of the 800 patients transplanted so far, 50 % are still alive up to 15 years. Of these, more than 80 % are off parenteral nutrition, in good healths, with good quality of live.

Adult↗

[Living donor liver transplantation of the right liver lobe between adults].

BACKGROUND AND OBJECTIVE: Adult living donor liver transplantation has been established in an increasing number of transplant centres during the last few years. Donor safety and risks are important criteria influencing the further development. We report our experience with 43 adult-to-adult right lobe living donor liver transplantations. METHODS: 43 patients (mean age: 49,8 +/- 16,0 years; f:m = 14:29) with end-stage liver disease received a right lobe liver graft from an adult living donor (mean age: 42,4 +/- 13,4 years; f:m = 27:16) between December 1999 and December 2001. An approval by the local ethics committee was obtained prior to the start of the programme and each donation. RESULTS: None of the donors experienced fatal or long-term complications. The rate of surgical complications in donors (biliary leakage, bleeding) was 9 %. Actuarial recipient survival was 93 % after three months and 88 % after one year. Five patients had to be re-transplanted. Thus the actuarial 1-year graft survival was 79 %. Biliary complications occurred in 14 % of all recipients. CONCLUSION: According to our experience, living donor liver transplantation of the right hepatic lobe is a safe and effective procedure. Especially for patients in acute and chronic liver failure, who otherwise would have died on the waiting list, this approach offers a life-saving option.

Adult↗

Primary human liver cells as source for modular extracorporeal liver support--a preliminary report.

Cell-based extracorporeal liver support is an option to assist or replace the failing organ until regeneration or until transplantation can be performed. The use of porcine cells or tumor cell lines is controversial. Primary human liver cells, obtained from explanted organs found to be unsuitable for transplantation, are a desirable cell source as they perform human metabolism and regulation. The Modular Extracorporeal Liver Support (MELS) concept combines different extracorporeal therapy units, tailored to suit the individual and intra-individual clinical needs of the patient. A multi-compartment bioreactor (CellModule) is loaded with human liver cells obtained by 5-step collagenase liver perfusion. A cell mass of 400 g - 600 g enables the clinical application of a liver lobe equivalent hybrid organ. A detoxification module enables single pass albumin-dialysis via a standard high-flux dialysis filter, and continuous veno-venuous hemodiafiltration may be included if required. Cells from 54 human livers have been isolated (donor age: 56 +/- 13 years, liver weight: 1862 +/- 556 g resulting in a viability of 55.0 +/- 15.9%). These grafts were not suitable for LTx, due to steatosis (54%), cirrhosis (15%), fibrosis (9%), and other reasons (22%). Out of 36 prepared bioreactors, 10 were clinically used to treat 8 patients with liver failure. The overall treatment time was 7-144 hours. No adverse events were observed. Initial clinical applications of the bioreactor evidenced the technical feasibility and safety of the system.

Bioreactors↗

Analysis of allogeneic versus xenogeneic auxiliary organ perfusion in liver failure reveals superior efficacy of human livers.

PURPOSE: To compare the efficacy of allogeneic and xenogeneic extracorporeal liver perfusion (ECLP). METHODS: An Internet-based keyword search was performed in the established online databases. Univariate and multivariate analysis of variance (general linear method) were performed. RESULTS: Data from 198 patients were included in the statistical analysis, 142 of whom were treated by ECLP using porcine livers. Baboon livers were used in 29 patients, human livers in 14, and other or mixed species in 13 patients. Pig liver perfusions resulted in a 20% long-term-survival whereas the use of human livers was significantly more successful (survival rate (SVR) 43%, p<0.05). Baboon livers also revealed superior success (41%; p<0.05). Twenty-three patients were treated after 1991, 12 surviving long-term (52%). The latter all belonged to a group of 14 patients who received combined treatment consisting of ECLP and LTx (SVR-86% in this subgroup). CONCLUSION: Allogeneic ECLP was accompanied by significantly improved outcome compared with discordant xenogeneic ECLP. The role of hyperacute rejection in acute liver failure with reduced complement levels remains controversial. Physiologic disparity between pig and man may be the even more decisive determinant of outcome.

Animals↗

Primary and secondary hepatic manifestation of neuroendocrine tumors.

BACKGROUND: In comparison with most other malignancies, in the treatment of metastatic neuroendocrine tumors one also has to consider endocrine symptoms and natural progression of disease. Since hepatic metastasis predominates and endocrine symptoms correlate with functional tumor mass, hepatic resection may improve prognosis or even cure patients. PATIENTS AND METHODS: We reviewed 41 consecutive patients with metastatic neuroendocrine tumors and four patients with primary hepatic disease presenting between 1989 and 1999. The neuroendocrine tumors were classified according to their origin, pattern of metastasis, endocrine activity, and histology. Operative therapy including hepatic resections of different extent, liver transplantation, and removal of the primary tumor was analyzed. The median survival after initial diagnosis and after hepatic resection were major parameters of outcome. RESULTS: There were 26 low-grade malignant, 12 high-grade malignant, 2 biphasically differentiated neuroendocrine carcinomas, and 5 pancreatic endocrine tumors. Hepatic resections were performed in 25 patients, resections of the primary tumor in 40 patients. The median survival after initial diagnosis was 49 months; 50.5 months in patients with hepatic resection versus 47 months in those with no liver surgery. CONCLUSION: Hepatic resection improved the outcome of patients with liver metastasis due to neuroendocrine tumors tendentiously but not significantly.

Adult↗

Proximal femoral bone loss and increased rate of fracture with a proximally hydroxyapatite-coated femoral component.

We performed a retrospective analysis of the clinical and radiological outcomes of total hip replacement using an uncemented femoral component proximally coated with hydroxyapatite. Of 136 patients, 118 who had undergone 124 primary total hip replacements were available for study. Their mean age was 66.5 years (19 to 90) and the mean follow-up was 5.6 years (4.25 to 7.25). At the final follow-up the mean Harris hip score was 92 (47.7 to 100). Periprosthetic femoral fractures, which occurred in seven patients (5.6%), were treated by osteosynthesis in six and conservatively in one. We had to revise five femoral components, one because of aseptic loosening, one because of septic loosening and three because of periprosthetic fracture. At the final follow-up there were definite signs of aseptic loosening in two patients. Radiologically, proximal femoral bone loss in Gruen zones I and VI was evident in 96.8% of hips, while bone hypertrophy in zones III and V was seen in 64.7%. In 24 hips (20.2%) the mean subsidence of the stem was 3.7 mm which occurred within the first 12 postoperative weeks. This indicated poor initial stability, which might have been aggravated by early weight-bearing. The high rate of failure in our study suggests that proximal femoral bone loss affects the long-term survival of the replacement.

Adult↗

Impact of immunoadsorption on xenogeneic extracorporeal pig liver perfusion: assessment of organ function during autologous reperfusion.

The shortage of liver grafts has resulted in an intensive search for alternative strategies of liver support in acute liver failure. Extracorporeal perfusion of pig livers (ECLP) is not a new concept, but recent improvements in cardiopulmonary bypass technology and new knowledge about xenogeneic immunologic mechanisms have made it a potential therapeutic modality. In previous suboptimal experimental and clinical models, no statements about the beneficial effect of long-lasting periods of ECLP were made. The aim of this study was to evaluate the capacity of pig liver for metabolic regeneration after xenogeneic ECLP under largely physiologic conditions. To delay hyperacute rejection (HAR), we utilized immunoadsorption (IA) of naturally preformed xenogeneic antibodies (XNAbs). This led to a stable xenogeneic ECLP for 45 min. However, IA was not able to prevent completely organ damage or loss of function resulting from insufficient autologous reperfusion. The inability to regenerate during autologous reperfusion provides a new measure of the function of a xenogeneic perfused pig liver. In addition, our results implicate that patients with fulminant liver failure will benefit from short perfusions with several fresh organs rather than from long perfusion with a single pig liver.

Animals↗

Impact of immunoadsorption on complement activation, immunopathology, and hepatic perfusion during xenogeneic pig liver perfusion.

BACKGROUND: The impact of antibody adsorption by immunoapheresis on liver damage, complement activation, and hepatic perfusion was evaluated against the background of an application in extracorporeal pig liver perfusion for hepatic coma. METHODS: Eighteen pig livers were ex vivo perfused close to physiological conditions with fresh human blood for 4 hr. The influence of the perfusion circuit was investigated by perfusions of the circuit in the absence of livers (group 1 [G1]; n=5). Livers were xenoperfused without modifications in group 2 (G2; n=6). In group 3 (G3; n=6), pure Sepharose columns were used prior to liver perfusion. Immunoapheresis with Ig-Therasorb 100 columns was used in group 4 (G4; n=6). RESULTS: IgG was reduced by 95%, IgM by 72%, and IgA by 82% in G4, but only by about 30% in G3 (P<0.05). C4d, Bb fragment, and C3a levels were significantly lower in G4 than in G3 and G2 (P<0.05) after 180 min. Immunoadsorption diminished antibody and complement deposition as well as hepatocellular damage in G4. Portal angiographies demonstrated improved hepatic perfusion in G4. CONCLUSION: Immunoapheresis reduced organ damage as well as complement activation and improved hepatic perfusion during xenogeneic pig liver perfusion.

Acute Disease↗