No description available.

This thesis describes a series of investigations into the problems that hamper the progress of myocardial preservation for transplantation in man. Six positive aspects of cardiac preservation have emerged from this study: - (1) A clear fluid hyperosmolar solution was formulated that adequately preserved viability of pig and baboon hearts. (2) A pneumatically powered portable preservation unit was designed which successfully preserved pig and baboon hearts when assessed by either functional testing or orthotopic transplantation. (3) A method of in vitro testing of hearts was developed that correlated with results from orthotopic transplantation. (4) A technique of cardiac autotransplantation in baboons was perfected. (5) The high release of lysosomal acid phosphatase during the period of hypothermic preservation was shown to be non-pathological and was reversible after a period of warm blood perfusion. (6) Successful preservation of human hearts for periods longer than 4 hours, not previously achieved, was obtained. The preservation solution and the portable preservation unit that emerged from this experimental study were thoroughly investigated before clinical application. During the development of this perfusate the author had numerous consultations and discussions with colleagues and senior members of neighbouring departments.

Liver transplantation is an accepted form of treatment in advanced liver disease. The procedure qualifies as one of the most severe surgical insults that can be inflicted upon a patient. Despite an ever increasing number of clinical and experimental transplants, a vast number of unanswered questions remains about the effects of storage and transplantation per se, on the functions of this complex organ. The administration of drugs and blood, with the effects of the donor state and preservation damage obscure changes in parameters that are inherently due only to the process of transplantation, Changes in calcium and other electrolyte homeostasis, liver function assessment, acid base metabolism and coagulation defects that are seen after liver grafting, are of particular interest to transplant physicians. Current clinically employed indices of liver function, such as enzyme levels, are notoriously lacking in specificity and sensitivity, The aim of the study was to investigate in the experimental situation, the effects of standardised preservation and transplantation, without the added effects of blood transfusion or immunosuppressive drug administration, upon calcium and other electrolyte homeostasis, liver function and coagulation changes. Furthermore, reliable indicators of liver function and/or damage were looked for. It was not an investigation into preservation methods to determine superiority of one or another of these methods, but an evaluation of changes occurring utilising established and clinically proven methods of preservation. Since researchers in the J.S. Marais laboratory, as well as their international counterparts, have experienced problems in successful storage of the pig liver for periods longer than 9 hours, a storage duration of six hours was chosen for maximum reproducibility. A brief overview of liver transplantation history has been given, available literature perused and used in assessment and discussion of data obtained. Five groups of six animals were used for orthotopic liver transplantation. Two groups were autografted with a non-flushed and Ringers lactate flushed liver respectively. Two groups were allografted with livers stored in Collins and University of Wisconsin solutions respectively. A fifth group was transplanted with a liver stored for six hours by surface cooling alone, without any flushing at all. The latter method has not been described in experimental or clinical liver transplantation before. No immunosuppression was used in any animal, to eliminate the effects of hepatotoxic drugs. No blood was transfused at any point during or after the transplant. An animal survival rate in excess of 90%, for seven days or longer, was aimed for and obtained. Blood sampling was done at short intervals in the immediate postoperative period up to six hours and daily for a week. All currently used clinical parameters were determined, as well as indicators which are known, but novel in transplantation. Changes in total and ionised calcium values occurred in all groups and no explanatory mechanism could be identified. There was no correlation in changes between total and ionised calcium, nor any correlation with calcium content of preservation fluids. A reciprocal change in magnesium was identified. Acid base metabolism was markedly changed during and after the transplant. An increase in serum bicarbonate indicated survival, and a persisting metabolic alkalosis was seen in all survivors. Sodium and potassium values did not show marked changes, except for a temporary hyperkalaemia immediately following reperfusion. Serum values of liver transaminases were not found to be of value to discriminate between groups. Protein metabolism was not affected by transplantation. Glucose metabolism was markedly affected by transplantation and even more so by poor function. Early return of normal glucose metabolism indicated survival. Lactic acid metabolism was conspicuously altered during transplantation and could also be regarded as an indicator of hepatocyte function. Coagulation in this series of experiments was affected negligibly and not thought to be influenced by transplantation of a normal liver under ideal circumstances. Thus, changes in values within groups and variance between groups, if any, were described and possible mechanisms causing variation discussed. New indicators of good liver function post-transplant were identified. The conclusion was reached that the process of transplantation per se does cause major changes in electrolyte and acid-base metabolism, but that coagulation was not affected by the process of successful preservation and transplantation.

Persufflation (PSF; gaseous oxygen perfusion) is an organ preservation technique with a potential for use in donor heart preservation. Improved heart preservation with PSF may improve outcomes by maintaining cardiac tissue quality in the setting of longer cold ischemia times and possibly increasing the number of donor hearts available for allotransplant. Published data suggest that PSF is able to extend the cold storage times for porcine hearts up to 14 hours without compromising viability and function, and has been shown to resuscitate porcine hearts following donation after cardiac death. This review summarizes key published work on heart PSF, including prospective implications and future directions for PSF in heart transplantation. We emphasize the potential impact of extending preservation times and expanding donor selection criteria in heart allotransplant. Additionally, the key issues that need to be addressed before PSF were to become a widely utilized preservation strategy prior to clinical heart transplantation are summarized and discussed.

Thesis (doctoral)--Lund University, 1998. / Added t.p. with thesis statement inserted.

Thesis (doctoral)--Lund University, 1998. / Added t.p. with thesis statement inserted.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / O transplante hepÃtico à o tratamento padrÃo para os portadores de doenÃa hepÃtica terminal. Com o refinamento da tÃcnica cirÃrgica, melhoria da eficÃcia dos imunossupressores, o entendimento da lesÃo de isquemia-reperfusÃo e o uso de soluÃÃes de preservaÃÃo mais fisiolÃgicas, houve um aumento considerÃvel da sobrevida do enxerto hepÃtico, e consequentemente, da sobrevida do paciente. A soluÃÃo de preservaÃÃo de Collins à a mais simples e a mais econÃmica, sendo utilizada desde 1969 principalmente no transplante renal. A soluÃÃo de Belzer à a mais utilizada mundialmente e preserva o enxerto hepÃtico por um perÃodo maior, entretanto com um custo mais elevado. O presente estudo compara 2 esquemas de perfusÃo hepÃtica utilizando a soluÃÃo de Collins e Belzer. A diferenÃa entre os dois grupos à que a soluÃÃo de Belzer infundida pela veia porta à substituÃda pela soluÃÃo de Collins. Foram avaliados 49 pacientes submetidos a transplante hepÃtico com doador falecido no Hospital UniversitÃrio Walter CantÃdio da Universidade Federal do CearÃ. A funÃÃo hepÃtica apÃs o transplante foi avaliada atravÃs das concentraÃÃes sÃricas de AST, ALT, Bilirrubinas e valores de INR (RelaÃÃo Normatizada Internacional do tempo de protrombina) no primeiro e sÃtimo dia pÃs-operatÃrio. O tempo de isquemia fria foi menor que 10 horas em todos os pacientes. NÃo houve diferenÃa entre os dois grupos nos parÃmetros analisados, exceto no INR do grupo em que foi infundida soluÃÃo de Collins na veia porta, que foi maior no 1 PO. Os dois esquemas de preservaÃÃo hepÃtica podem ser utilizados com seguranÃa, desde que observado um tempo de isquemia fria menor que 10 horas. Houve uma reduÃÃo do custo do transplante no grupo que utilizou um menor volume da soluÃÃo de Belzer / The hepatic transplant is the standard treatment for terminal hepatic illness. With the refinement of the surgical technique, improvement of the effectiveness of the immunosuppressive drugs, the better knowledge of the reperfusion injury and the use of more physiological solutions of preservation, had a considerable increase of the survival of hepatic graft. The Collinsâ preservation solution used since 1969 , in renal transplant, is simplest and most economic preservation solution. The Belzerâs solution is used world wide and preserves hepatic graft for a longer period, although more expensive. The present study it compares 2 projects of hepatic perfusion using the Collins and Belzerâs solution. The difference between the two groups is that the Belzerâs solution perfused for the portal vein is substituted by the solution of Collins. At Walter CantÃdio Hospital of the Federal University of the Cearà 49 patients submitted to hepatic transplant of deceased donors graft were evaluated. The hepatic function after the transplant was evaluated through parameters AST, ALT, INR and Bilirubin in first and the seventh postoperative day. The time of cold ischemia was less than 10 hours in all the patients. There was no difference between the two groups in the analyzed parameters, except in the INR of the group where Collinsâ solution in the portal vein was perfused, which was greater in the 1 postoperative day. The two projects of hepatic preservation can be used with security, as the cold ischemia time is less than 10 hours, however, it had a reduction of the cost of the liver transplant in the group that used a lesser volume of the solution of Belzer.

No description available.

Introdução: Apesar dos importantes avanços na preservação pulmonar alcançados nas últimas décadas esta questão permanece longe do ideal e representa um dos maiores problemas enfrentados pelos grupos de transplante pulmonar. O grupo da Suécia liderado pelo Prof. Stig Steen descreveu um novo método de preservação pulmonar chamado de ECMOtópico que foi publicado nos mesmos artigos que divulgaram o sistema de perfusão ex vivo. Todavia, este novo método nunca foi avaliado de forma comparativa contra a forma atualmente mais aceita de preservação pulmonar: a isquemia fria após infusão de solução de preservação. O presente estudo compara estas duas formas de preservação utilizando um modelo de avaliação pulmonar ex vivo. Como objetivos secundários foram estudados: a capacidade de recuperação da função pulmonar pelo sistema ex vivo e a utilidade do modelo experimental bloco pulmonar dividido. Métodos: Quatorze pulmões foram captados de sete doadores em morte encefálica negados para transplante pulmonar. Após a preservação inicial com perfusão anterógrada de solução de LPD-glicose o bloco pulmonar foi dividido, sendo cada lado submetido a um médoto diferente de preservação: ECMO-tópico ou isquemia fria por oito horas. Após este período os pulmões foram re-conectados e avaliados em um sistema de reperfusão pulmonar ex vivo estudando-se parâmetros funcionais e histológicos; biópsias pulmonares foram coletadas em três tempos em cada lado. As variáveis funcionais estudadas foram: capacidade de oxigenação (CO), pressão de artéria pulmonar (PAP) e resistência vascular pulmonar (RVP). As variáveis histológicas foram: escore de lesão pulmonar (ELP), contagem de células apoptóticas (CCA) e estudo de microscopia eletrônica de transmissão. Resultados: Sete casos foram incluídos. A idade média foi de 53.86 anos (±16.7); sexo masculino em 4 casos (57.1%); causa da morte encefálica: acidente vascular encefálico hemorrágico em 5 doadores e trauma crânio encefálico em 2. O lado submetido ao ECMO-tópico: direito em 4 e esquerdo em 3 casos. A média da CO foi 468.00 mmHg (±81.69) no grupo ECMOtópico e 455.86 (±54.05) no grupo isquemia fria (p=0. 758); a mediana da PAP foi de 140 mmHg(120 160) para o ECMO-tópico e 140mmHg(140 150) para isquemia fria (p=0,285); a mediana da RVP 459 dina.s.cm-5 (432,43 492,30) no grupo ECMO-tópico e 474,5 dina.s.cm-5 (459,01 545,45) no grupo isquemia fria (p=0,285). As médias dos escores de lesão pulmonar encontrados foram: para o grupo ECMO-tópico em T1 6,285 (±4,029), em T2 8,714 (±7,714) e em T3 9,571 (±7,857); já no grupo isquemia fria as médias foram em T1 7,571 (±4,429), em T2 7,714 (±4,785) e em T3 7,857 (±6,121) p = 0,531. As médias das contagens de células apoptóticas foram: para o grupo ECMO-tópico em T1 16,71(±2,545), em T2 20,71 (±5,843) e em T3 25,00 (±9,34); no grupo isquemia fria em T1 18,57 (±5,118), em T2 17,57 (±3,014) e em T3 24,86 (±10,374) p=0,803. O estudo de microscopia eletrônica de transmissão não demonstrou diferenças entre os grupos. Conclusões: Neste estudo o ECMOtópico não demonstrou melhora na preservação pulmonar, comparado a isquemia fria, em nenhum dos parâmetros estudados . O modelo de reperfusão pulmonar ex vivo permitiu importante melhora na função pulmonar, e o modelo experimental com bloco pulmonar dividido demonstrou ser um método adequado para estudos experimentais comparativos com pulmões humanos / Background: Besides the important advances in lung preservation reached in last decades this subject continues far from ideal and still represent a major challenge for the lung transplant groups. The Swedish group lead by Prof. Stig Steen has described a new method of preservation so called topical- ECMO along with the ex vivo perfusion system. However this new method has never been tested against the most popular formula of preservation: cold ischemia after single flush perfusion. This study compares these two forms of lung preservation on an ex vivo evaluation model. As secondarys end-points we also study the ex vivo lung perfusion capacity for recover damaged lungs to transplant and the usefulness of the lung bloc split model for experimental study of human lungs. Methods: Fourteen lungs were retrieved from seven brain-dead organ donors refused for transplantation. After initial preservation with single flush of LPD glucose, the lung bloc was divided and each side was preserved by topical-ECMO or cold ischemia for 8 hours. After this the bloc was reconnected than assessed on ex vivo lung system for functional and histological parameters; lung biopsies were collect in three different times on each side. The functional variables assessed were: oxygenation capacity (OC), pulmonary artery pressure (PAP) and pulmonary vascular resistance (PVR). The histological variables were: lung injury score (LIS), apoptotic cells counting and transmission electron microscopy study. Results: Seven cases were included. Mean age 53.86 years (±16.7); male 4 (57.1%); cause of death: hemorrhagic stroke for 5 donors and head trauma for 2. Side of topical- ECMO: Right 4 e Left 3. The mean OC was 468.00 mmHg (±81.69) on topical-ECMO group and 455.86 (±54.05) on Cold Ischemia group (p=0. 758); median PAP median was 140 mmHg(120 160) for topical-ECMO and 140mmHg (140 150) for Cold Ischemia (p=0,285); median PVR 459 dina.s.cm-5 (432,43 492,30) on topical-ECMO group and 474,5 dina.s.cm-5 (459,01 545,45) on Cold Ischemia group (p=0,285). The median for LIS was: topical-ECMO group on T1 6,285 (±4,029), on T2 8,714 (±7,714) and on T3 9,571 (±7,857); Cold Ischemia group on T1 7,571 (±4,429) on T2 7,714 (±4,785) and on T3 7,857 (±6,121) p=0,531. For apoptotic cell counting: topical-ECMO group on T1 16,71(±2,545), on T2 20,71 (±5,843) and on T3 25,00 (±9,34); for Cold Ischemia group it was on T1 18,57 (±5,118), on T2 17,57 (±3,014) and on T3 24,86 (±10,374) p=0,803. The transmission electron microscopy study shows no difference between groups. Conclusions: In our study the topical-ECMO failed to show improvement of lung preservation compared with the cold ischemia in all studied parameters. However the ex vivo lung perfusion model was responsible for a important increase on lung function, and the lung bloc split model appears as a reliable method for experimental human lung studies

Introdução: Apesar dos importantes avanços na preservação pulmonar alcançados nas últimas décadas esta questão permanece longe do ideal e representa um dos maiores problemas enfrentados pelos grupos de transplante pulmonar. O grupo da Suécia liderado pelo Prof. Stig Steen descreveu um novo método de preservação pulmonar chamado de ECMOtópico que foi publicado nos mesmos artigos que divulgaram o sistema de perfusão ex vivo. Todavia, este novo método nunca foi avaliado de forma comparativa contra a forma atualmente mais aceita de preservação pulmonar: a isquemia fria após infusão de solução de preservação. O presente estudo compara estas duas formas de preservação utilizando um modelo de avaliação pulmonar ex vivo. Como objetivos secundários foram estudados: a capacidade de recuperação da função pulmonar pelo sistema ex vivo e a utilidade do modelo experimental bloco pulmonar dividido. Métodos: Quatorze pulmões foram captados de sete doadores em morte encefálica negados para transplante pulmonar. Após a preservação inicial com perfusão anterógrada de solução de LPD-glicose o bloco pulmonar foi dividido, sendo cada lado submetido a um médoto diferente de preservação: ECMO-tópico ou isquemia fria por oito horas. Após este período os pulmões foram re-conectados e avaliados em um sistema de reperfusão pulmonar ex vivo estudando-se parâmetros funcionais e histológicos; biópsias pulmonares foram coletadas em três tempos em cada lado. As variáveis funcionais estudadas foram: capacidade de oxigenação (CO), pressão de artéria pulmonar (PAP) e resistência vascular pulmonar (RVP). As variáveis histológicas foram: escore de lesão pulmonar (ELP), contagem de células apoptóticas (CCA) e estudo de microscopia eletrônica de transmissão. Resultados: Sete casos foram incluídos. A idade média foi de 53.86 anos (±16.7); sexo masculino em 4 casos (57.1%); causa da morte encefálica: acidente vascular encefálico hemorrágico em 5 doadores e trauma crânio encefálico em 2. O lado submetido ao ECMO-tópico: direito em 4 e esquerdo em 3 casos. A média da CO foi 468.00 mmHg (±81.69) no grupo ECMOtópico e 455.86 (±54.05) no grupo isquemia fria (p=0. 758); a mediana da PAP foi de 140 mmHg(120 160) para o ECMO-tópico e 140mmHg(140 150) para isquemia fria (p=0,285); a mediana da RVP 459 dina.s.cm-5 (432,43 492,30) no grupo ECMO-tópico e 474,5 dina.s.cm-5 (459,01 545,45) no grupo isquemia fria (p=0,285). As médias dos escores de lesão pulmonar encontrados foram: para o grupo ECMO-tópico em T1 6,285 (±4,029), em T2 8,714 (±7,714) e em T3 9,571 (±7,857); já no grupo isquemia fria as médias foram em T1 7,571 (±4,429), em T2 7,714 (±4,785) e em T3 7,857 (±6,121) p = 0,531. As médias das contagens de células apoptóticas foram: para o grupo ECMO-tópico em T1 16,71(±2,545), em T2 20,71 (±5,843) e em T3 25,00 (±9,34); no grupo isquemia fria em T1 18,57 (±5,118), em T2 17,57 (±3,014) e em T3 24,86 (±10,374) p=0,803. O estudo de microscopia eletrônica de transmissão não demonstrou diferenças entre os grupos. Conclusões: Neste estudo o ECMOtópico não demonstrou melhora na preservação pulmonar, comparado a isquemia fria, em nenhum dos parâmetros estudados . O modelo de reperfusão pulmonar ex vivo permitiu importante melhora na função pulmonar, e o modelo experimental com bloco pulmonar dividido demonstrou ser um método adequado para estudos experimentais comparativos com pulmões humanos / Background: Besides the important advances in lung preservation reached in last decades this subject continues far from ideal and still represent a major challenge for the lung transplant groups. The Swedish group lead by Prof. Stig Steen has described a new method of preservation so called topical- ECMO along with the ex vivo perfusion system. However this new method has never been tested against the most popular formula of preservation: cold ischemia after single flush perfusion. This study compares these two forms of lung preservation on an ex vivo evaluation model. As secondarys end-points we also study the ex vivo lung perfusion capacity for recover damaged lungs to transplant and the usefulness of the lung bloc split model for experimental study of human lungs. Methods: Fourteen lungs were retrieved from seven brain-dead organ donors refused for transplantation. After initial preservation with single flush of LPD glucose, the lung bloc was divided and each side was preserved by topical-ECMO or cold ischemia for 8 hours. After this the bloc was reconnected than assessed on ex vivo lung system for functional and histological parameters; lung biopsies were collect in three different times on each side. The functional variables assessed were: oxygenation capacity (OC), pulmonary artery pressure (PAP) and pulmonary vascular resistance (PVR). The histological variables were: lung injury score (LIS), apoptotic cells counting and transmission electron microscopy study. Results: Seven cases were included. Mean age 53.86 years (±16.7); male 4 (57.1%); cause of death: hemorrhagic stroke for 5 donors and head trauma for 2. Side of topical- ECMO: Right 4 e Left 3. The mean OC was 468.00 mmHg (±81.69) on topical-ECMO group and 455.86 (±54.05) on Cold Ischemia group (p=0. 758); median PAP median was 140 mmHg(120 160) for topical-ECMO and 140mmHg (140 150) for Cold Ischemia (p=0,285); median PVR 459 dina.s.cm-5 (432,43 492,30) on topical-ECMO group and 474,5 dina.s.cm-5 (459,01 545,45) on Cold Ischemia group (p=0,285). The median for LIS was: topical-ECMO group on T1 6,285 (±4,029), on T2 8,714 (±7,714) and on T3 9,571 (±7,857); Cold Ischemia group on T1 7,571 (±4,429) on T2 7,714 (±4,785) and on T3 7,857 (±6,121) p=0,531. For apoptotic cell counting: topical-ECMO group on T1 16,71(±2,545), on T2 20,71 (±5,843) and on T3 25,00 (±9,34); for Cold Ischemia group it was on T1 18,57 (±5,118), on T2 17,57 (±3,014) and on T3 24,86 (±10,374) p=0,803. The transmission electron microscopy study shows no difference between groups. Conclusions: In our study the topical-ECMO failed to show improvement of lung preservation compared with the cold ischemia in all studied parameters. However the ex vivo lung perfusion model was responsible for a important increase on lung function, and the lung bloc split model appears as a reliable method for experimental human lung studies