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1.
BMC Gastroenterol ; 21(1): 252, 2021 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-34098880

RESUMEN

BACKGROUND: The aim of this study was to analyze prognostic indicators of in-hospital mortality among patients listed for urgent liver transplantation (LT) for non-acetaminophen (APAP)-induced acute liver failure (ALF). METHODS: ALF patients listed for LT according to the King's College Criteria were retrospectively reviewed. Variables were recorded from medical records and electronic databases (HCMED and RedCap). RESULTS: The study included 100 patients, of which 69 were subject to LT and 31 died while waiting for LT. Patients were 35.5 ± 14.73 years old, and 78% were females. The main etiologies were virus (17%), drug-induced (32%), autoimmune (15%), and indeterminate hepatitis (31%). The prioritization-to-LT time interval was 1.5 days (0-9). The non-LT patients showed higher lactate (8.71 ± 5.36 vs. 4.48 ± 3.33 mmol/L), creatinine (229 ± 207 vs. 137 ± 136 µm/L), MELD (44 ± 8 vs. 38 ± 8), and BiLE scores (15.8 ± 5.5 vs. 10.3 ± 4.1) compared to LT patients (p < 0.05). Multiple logistic regression analysis identified creatinine and lactate as independent prognostic factors, and a creatinine-lactate (CL) score was developed. ROC analysis showed that creatinine, lactate, MELD, BiLE, and CL scores had considerable specificity (71-88%), but only BiLE, lactate, and CL presented high sensitivities (70%, 80%, and 87% respectively). AUCs were 0.696 for creatinine, 0.763 for lactate, 0.697 for MELD, 0.814 for BiLE, and 0.835 for CL. CONCLUSIONS: CL and BiLE scores predict mortality with more accuracy than MELD in patients with ALF during prioritization time. Creatinine and lactate are independent prognostic factors for mortality.


Asunto(s)
Fallo Hepático Agudo , Trasplante de Hígado , Adulto , Creatinina , Femenino , Humanos , Ácido Láctico , Fallo Hepático Agudo/inducido químicamente , Fallo Hepático Agudo/cirugía , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Adulto Joven
4.
BMC Med Imaging ; 15: 37, 2015 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-26385342

RESUMEN

BACKGROUND: Abernethy malformation is a rare congenital vascular abnormality in which the portal vein bypasses the liver and drains directly into the inferior vena cava. Diagnosis is complex and requires good quality imaging methods to identify details in systemic and portal circulation in order to establish diagnostic confirmation and treatment strategy. In this study we highlight the significance of the use of CT scans and Color Doppler Duplex Ultrasound for the diagnosis, treatment and evolution assessment in two adults with Abernethy malformation. CASE PRESENTATION: The diagnosis and the treatment of two patients with Abernethy malformation by CT scan and Color Doppler Duplex Ultrasound is described. One patient was submitted to liver transplantation due to chronic liver disease and multiple nodules diagnosed as adenoma. The other patient had normal liver function and a mild neurological and psychomotor dysfunction, therefore we adopted clinical treatment and close liver parenchyma evaluation and nodule surveillance, using an imaging approach involving intercalating CT scan and Color Doppler Duplex Ultrasound every 6 months. We highlight some important direct and indirect findings of non-invasive imaging methods. CONCLUSION: Abernethy malformation requires meticulous image diagnosis to improve treatment and avoid iatrogenic procedures. CT scans and Color Doppler Duplex Ultrasound are both efficient methods for diagnosis, treatment planning and evolution assessment of patients with Abernethy malformation.


Asunto(s)
Tomografía Computarizada por Rayos X/métodos , Ultrasonografía Doppler en Color/métodos , Malformaciones Vasculares/patología , Vena Cava Inferior/patología , Diagnóstico Diferencial , Femenino , Humanos , Hepatopatías/cirugía , Trasplante de Hígado , Persona de Mediana Edad , Malformaciones Vasculares/complicaciones , Vena Cava Inferior/diagnóstico por imagen , Adulto Joven
5.
Surg Radiol Anat ; 36(2): 105-9, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23817807

RESUMEN

Accurate knowledge of the anatomy of the bile ducts is critical for successfully hepato-biliary surgery. We describe the anatomical variations of the confluence of the bile ducts, their branches patterns, frequency and classification. From 1996 to 2011, we have collected data of the bile duct confluence. 2,032 and 1,014 anatomical variations of right and left bile ducts, respectively, were reviewed and classified according to the branching pattern. The frequencies of each type of the right hepatic duct (RHD) were as follows: Type A1-1,247 (61.3%); Type A2-296 (14.5%); Type A3-272 (13.3%); Type A4-124 (6.1%); Type A5-21 (1%) and others-72 (3.5%) and, for the left hepatic duct (LHD) was as follows: Type B1-773 (76.2%); Type B2-153 (15%); Type B3-38 (3.7%); Type B4-9 (0.8%); Type B5-29 (2.8%) and others-12 (1.1%). Atypical branching patterns of both the right and left hepatic ducts were found in 14 and 8%, respectively. The two most common variations of the RHD were right anterior and posterior hepatic ducts join together to form the RHD and trifurcation where the RHD is absent and right anterior and posterior hepatic ducts join directly to the confluence with the LHD to form the common hepatic duct. The two most common variations in the LHD were segment IV drainage to the left and right hepatic ducts.


Asunto(s)
Variación Anatómica/fisiología , Conductos Biliares/anatomía & histología , Conductos Biliares/cirugía , Colangiografía/métodos , Humanos , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X/métodos , Ultrasonografía Doppler/métodos
6.
Transplant Proc ; 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38749861

RESUMEN

Anorectal transplantation (ART) is an obvious therapeutic option for treating permanent colostomy and severe fecal incontinence. The rat is the best model for beginning studies of a new surgical procedure. In this article, we review ART techniques in rats. METHODS: We reviewed articles on rat and ART keywords throughout Cochrane Library, MEDLINE, and EMBASE. Five articles were found, of which 2 used autotransplantations, 1 performed only transplantation of the anal canal and extraperitoneal rectum, and another performed transplantation of the entire intestine, including the anus, but only followed for 2 hours. RESULTS: In 2016, we performed the first series of isoART (n = 6) and alloART (n = 9) of the entire anorectal segment and micro-anastomosis of the inferior mesenteric vessels. Two animals died due to surgical complications, and the others survived until the endpoint of the experiment. Five animals with alloART showed clinical signs of immunologic rejection 3 weeks after transplantation, and autopsy histology on postoperative day 30 revealed moderate to severe rejection in the allografts. CONCLUSIONS: In this review, we observed that ART in rats is viable and may allow further physiologic and immunologic studies of this procedure, a potential treatment for severe incontinence and permanent colostomy.

7.
Transplant Proc ; 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38890075

RESUMEN

BACKGROUND: The swine is a valuable model for preclinical research and surgical technique training. Induction of Type I diabetes is achieved by total pancreatectomy, therefore these animals may be used in several research studies, including islet transplantation field. Given the lack of information in the literature, the purpose of this work is to describe anatomic aspects of swine pancreas, the total pancreatectomy surgical technique, intra- and postoperative complications and the autopsy results. MATERIAL AND METHODS: Five hybrid male pigs, 20-35 kg, submitted to total pancreatectomy with duodenum, bile duct, and spleen preservation. Postoperatively, daily clinical assessment and capillary blood glucose collection were performed. At the end of the 30-day period or in the occurrence of serious clinical complications, euthanasia and autopsy were performed. RESULTS: The average duration of surgery was 128 minutes, without intraoperative deaths or anesthesia induction failures. The median survival was 6.6 days. Postoperative complications were weight loss (3), emesis (2), constipation (2), abdominal distension (2), diarrhea (1), and loss of appetite (1). All animals were euthanized due to serious complications. Two animals presented surgical complications (duodenal necrosis with gastroparesis and internal hernia with intestinal necrosis). The other 3 animals presented serious clinical complications related to exocrine pancreatic insufficiency due to deficiency of pancreatic enzymes. Glycemic values above 200 mg/dL were found on the first postoperative day and above 300 mg/dL on the seventh day in all animals. CONCLUSION: A model of total pancreatectomy with duodenum, spleen, and bile duct preservation in pigs was established. All animals became diabetic, however, animals without postoperative complications were euthanized due to serious complications related to pancreas exocrine insufficiency.

8.
Arq Gastroenterol ; 60(3): 383-392, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37792769

RESUMEN

•In this review, we described different murine models of carcinogenesis: classic models, new transgenic and combined models, that reproduce the key points for HCC and CCA genesis allowing a better understanding of its genetic physiopathological, and environmental abnormalities. •Each model has its advantages, disadvantages, similarities, and differences with the corresponding human disease and should be chosen according to the specificity of the study. Ultimately, those models can also be used for testing new anticancer therapeutic approaches. •Cholangiocarcinoma has been highlighted, with an increase in prevalence. This review has an important role in understanding the pathophysiology and the development of new drugs. Background - This manuscript provides an overview of liver carcinogenesis in murine models of hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA). Objective - A review through MEDLINE and EMBASE was performed to assess articles until August 2022.Methods - Search was conducted of the entire electronic databases and the keywords used was HCC, CCA, carcinogenesis, animal models and liver. Articles exclusion was based on the lack of close relation to the subject. Carcinogenesis models of HCC include HCC induced by senescence in transgenic animals, HCC diet-induced, HCC induced by chemotoxicagents, xenograft, oncogenes, and HCC in transgenic animals inoculated with B and C virus. The models of CCA include the use of dimethylnitrosamine (DMN), diethylnitrosamine (DEN), thioacetamide (TAA), and carbon tetrachloride (CCl4). CCA murine models may also be induced by: CCA cells, genetic manipulation, Smad4, PTEN and p53 knockout, xenograft, and DEN-left median bile duct ligation. Results - In this review, we described different murine models of carcinogenesis that reproduce the key points for HCC and CCA genesis allowing a better understanding of its genetic, physiopathological, and environmental abnormalities. Conclusion - Each model has its advantages, disadvantages, similarities, and differences with the corresponding human disease and should be chosen according to the specificity of the study. Ultimately, those models can also be used for testing new anticancer therapeutic approaches.


Asunto(s)
Neoplasias de los Conductos Biliares , Carcinoma Hepatocelular , Colangiocarcinoma , Neoplasias Hepáticas , Animales , Ratones , Neoplasias de los Conductos Biliares/genética , Neoplasias de los Conductos Biliares/patología , Conductos Biliares Intrahepáticos/patología , Carcinogénesis , Carcinoma Hepatocelular/patología , Colangiocarcinoma/genética , Colangiocarcinoma/inducido químicamente , Modelos Animales de Enfermedad , Neoplasias Hepáticas/patología
9.
Acta Cir Bras ; 38: e386023, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38055396

RESUMEN

PURPOSE: After partial hepatectomy (PH), the remaining liver (RL) undergoes regenerative response proportional to the host. Limited literature exists on hepatic viability after tissue injury during hypothermic preservation. Spectroscopy measures cellular fluorescence and is explored for tissue characterization and parameter investigation. This study aimed to assess fluorescence analysis (spectroscopy) in evaluating liver viability and its relationship with hepatic tissue regeneration 24 hours after PH. Additionally, we analyzed liver regeneration in RL after 70% partial hepatectomy under hypothermic conditions with laser irradiation. METHODS: Fifty-six Wistar rats were divided into four groups: total non-perfused liver (control), total perfused liver, partial hepatectomy "in situ", and partial hepatectomy "ex situ". Tissue analysis was performed at 0 and 24 hours using spectroscopy with laser devices emitting at 532 (green) and 405 nm (violet). RESULTS: Spectroscopy identified tissue viability based on consistent results with Ki67 staining. The fluorescence spectra and Ki67 analysis displayed similar patterns, linking proliferative activity and absorption intensity. CONCLUSIONS: Fluorescence spectroscopy proves to be promising for real-time analysis of cellular activity and viability. Metabolic activity was observed in groups of live animals and hypothermically preserved samples, indicating cellular function even under blood deprivation and hypothermic conditions.


Asunto(s)
Hepatectomía , Hígado , Ratas , Animales , Espectrometría de Fluorescencia , Antígeno Ki-67/metabolismo , Ratas Wistar , Hígado/cirugía , Hígado/metabolismo , Hepatectomía/métodos , Regeneración Hepática/fisiología , Isquemia/metabolismo , Rayos Láser
10.
Front Surg ; 10: 1086651, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37151860

RESUMEN

Background: Multivisceral transplantation of pelvic organs would be a potential treatment for severe pelvic floor dysfunction with fecal and urinary incontinence, extensive perineal trauma, or congenital disorders. Here, we describe the microsurgical technique of multivisceral transplantation of pelvic organs, including the pelvic floor, in rats. Donor operation: We performed a perineal (including the genitalia, anus, muscles, and ligaments) and abdominal incision. The dissection progressed near the pelvic ring, dividing ligaments, muscles, external iliac vessels, and pudendal nerves, allowing pelvic floor mobilization. The aorta and vena cava were isolated distally, preserving the internal iliac and gonadal vessels. The graft containing the skin, muscles, ligaments, bladder, ureter, rectum, anus and vagina, uterus and ovarian (female), or penile, testis and its ducts (male) was removed en bloc, flushed, and cold-stored. Recipient operation: The infrarenal aorta and vena cava were isolated and donor/recipient aorta-aorta and cava-cava end-to-side microanastomoses were performed. After pelvic floor and viscera removal, we performed microanastomoses between the donor and the recipient ureter, and the rectum and pudenda nerves. The pelvic floor was repositioned in its original position (orthotopic model) or the abdominal wall (heterotopic model). We sacrificed the animals 2 h after surgery. Results: We performed seven orthotopic and four heterotopic transplantations. One animal from the orthotopic model and one from the heterotopic model died because of technical failure. Six orthotopic and three heterotopic recipients survived up to 2 h after transplantation. Conclusion: The microsurgical technique for pelvic floor transplantation in rats is feasible, achieving an early survival rate of 81.82%.

11.
Acta Cir Bras ; 37(1): e370103, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35262597

RESUMEN

INTRODUCTION: Portal hypertension still represents an important health problem worldwide. In the search for knowledge regarding this syndrome, experimental studies with animal models have proven to be useful to point the direction to be taken in future randomized clinical trials. PURPOSE: To validate the experimental model of portal hypertension and esophagogastric varices in a medium-sized animal. METHODS: This study included five minipigs br1. Midline laparotomy with dissection of the portal vein and production of a calibrated stenosis of this vein was performed. Measurement of pressure in the portal venous and digestive endoscopic were performed before and five weeks after the production of a stenosis. RESULTS: All animals were 8 months old, average weight of 17 ± 2.5 kg. The mean pressure of the portal vein immediately before the partial ligation of the portal vein was 8.9 + 1.6 mm Hg, with 26.6 + 5.4 mm Hg in the second measurement five weeks later (p < 0.05). No gastroesophageal varices or hypertensive portal gastropathy were seen at endoscopy procedures in our sample at any time in the study. CONCLUSION: Portal vein ligation in minipigs has been validated in the production of portal hypertension, but not in the formation of esophageal varices.


Asunto(s)
Várices Esofágicas y Gástricas , Hipertensión Portal , Várices , Animales , Endoscopía , Várices Esofágicas y Gástricas/cirugía , Modelos Teóricos , Proyectos Piloto , Vena Porta/cirugía , Porcinos , Porcinos Enanos
12.
Pharmacol Res Perspect ; 10(6): e01027, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36404629

RESUMEN

Liver ischemia-reperfusion (IR) injury is associated with poor outcome after liver transplantation and liver resections. Hexafluoroisopropanol (HFIP) is a tri-fluorinated metabolites of volatile anesthetics and has modulatory effects on inflammation that have been observed mainly in cell culture experiments. In this survey, we investigated the effects of HFIP in a rat model of normothermic hepatic ischemia-reperfusion injury. Twenty-four male Wistar rats were randomized into three groups: (1) control in which animals were submitted to 30 min of partial liver ischemia with resection of non-ischemic liver lobes immediate after reperfusion, (2) pre-ischemia (PI) group in which animals received intravenous HFIP (67 mg/kg) 5 min before liver ischemia, and (3) pre-reperfusion (PR) group in which animals received intravenous HFIP (67 mg/kg) 5 min before reperfusion. Four hours after reperfusion, all animals were euthanized for sample collection. Aspartate and alanine transaminases, glucose, and high mobility group box-1 (HMGB-1) protein concentrations showed a significant decreased, and malondialdehyde was increased in the PR group compared with control and PI groups. Interleukin 6 (IL-6) was increased in the PI group compared with control and PR groups. IL-10 and -12 were increased in the PR and PI groups, respectively, when compared with the control group. Glucose decreased in the PR when compared with the control group. Post-conditioning with HFIP led to a decrease in hepatocellular injury and was associated with a downregulation of HMGB-1. The HFIP resulted in a better control of inflammatory response to ischemia-reperfusion even without causing a reduction in oxidative stress.


Asunto(s)
Daño por Reperfusión , Animales , Masculino , Ratas , Regulación hacia Abajo , Glucosa/metabolismo , Isquemia/complicaciones , Isquemia/metabolismo , Hígado/metabolismo , Ratas Wistar , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/etiología , Daño por Reperfusión/metabolismo
13.
Transplant Proc ; 54(5): 1320-1323, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35537876

RESUMEN

BACKGROUND: Living donor liver transplant (LDLT) is a valuable therapeutic option for overcoming the deceased donor shortage. Modified right lobe graft (MRLG) keeps the middle hepatic vein (MHV) trunk with the remnant liver to improve donor safety. Hemostasis in the MHV tributary reconstruction can be tricky; surgical stitches and energy coagulation are ineffective. Fibrin glues are excellent vascular sealants but are poor in maintaining hemostasis in an active hemorrhage or preventing resection surface-related complications after liver resection. We propose applying fibrin sealant during back table graft preparation to seal the hepatic edge and MHV reconstruction to avoid bleeding after graft revascularization. METHODS: Our retrospective cohort study included all adult patients undergoing LDLT between August 2017 and December 2021. During the back table procedure, we performed the reconstruction of the inferior right hepatic vein and/or MHV tributaries from segment 5 (V5) and segment 8 (V8) using a vein harvested from a nonrelated deceased donor. Before initiating the hepatic graft implantation, we applied fibrin sealant in the resected parenchyma, especially in the V5 and V8 anastomosis, to seal the hepatic edge and hepatic vein reconstruction. RESULTS: No bleeding was identified in the hepatic edge, and blood product transfusion was unnecessary for any recipients after reperfusion. CONCLUSION: In LDLT using MRLG with MHV reconstruction, the fibrin sealant, when applied on the raw hepatic surface, and vascular reconstruction during back table graft preparation avoided bleeding after graft revascularization.


Asunto(s)
Trasplante de Hígado , Donadores Vivos , Adulto , Adhesivo de Tejido de Fibrina , Hemorragia/etiología , Hemorragia/prevención & control , Venas Hepáticas , Humanos , Hígado/irrigación sanguínea , Hígado/cirugía , Trasplante de Hígado/efectos adversos , Trasplante de Hígado/métodos , Reperfusión , Estudios Retrospectivos
14.
Transplant Proc ; 54(5): 1295-1299, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35768298

RESUMEN

BACKGROUND: Liver transplant (LT) is the standard therapy for end-stage liver disease. Advances in surgical techniques and immunosuppression protocols improved the results of LT by increasing long-term survival. Nevertheless, an adequate match between the donor and recipient is paramount for avoiding futile liver transplants. We aimed to identify the prognostic factors in donor-recipient LT matching. METHODS: Retrospective analysis of adult LT was conducted from January 2006 to December 2018, which included the following transplant modalities: deceased donor LT (DDLT), living donor LT (LDLT), combined liver-kidney transplant (CLKT), and domino LT (DLT). RESULTS: Among 1101 patients who underwent LT, 958 patients underwent DDLT, 92 patients underwent LDLT, 45 patients underwent CLKT, and 6 patients underwent DLT. The overall survival (OS) in 1, 5, and 10 years were 89%, 83%, and 82%, respectively. For DDLT, OS in 1, 5, and 10 years were 91%, 84%, and 82%, respectively. For LDLT, OS in 1, 5, and 10 years were 89%, 72%, and 69%, respectively. For CKLT, OS in 1, 5, and 10 years were 90%, 71%, and 71%, respectively. None of the DLT patients died. For DDLT, the factors that affected OS were the presence of fulminant liver failure (odds ratio [OR], 2.23; 95% CI, 1.18-4.18; P = .001), hemodialysis before LT (OR, 2.12; 95% CI, 1.27-3.5; P = .004), retransplant (OR, 4.74; 95% CI, 2.75-8.17; P = .000), and recipient age >60 years (OR, 1.86; 95% CI, 1.27-2.73; P = .001). For hospitalization before LT (due to an acute-on-chronic liver failure), the OR was 2.10 (95% CI, 1.29-3.42; P = .003). Donor intensive care unit time >7 days (OR, 1.46; 95% CI, 1.04-2.06; P = .02) was also associated with overall mortality. CONCLUSIONS: We identified prognostic factors in donor-recipient LT matching. Furthermore, we demonstrated that an adequate organ allocation with donor-recipient selection might increase graft survival and reduce waiting list mortality.


Asunto(s)
Enfermedad Hepática en Estado Terminal , Trasplante de Hígado , Adulto , Enfermedad Hepática en Estado Terminal/diagnóstico , Enfermedad Hepática en Estado Terminal/cirugía , Humanos , Trasplante de Hígado/métodos , Donadores Vivos , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Resultado del Tratamiento
15.
Transplant Proc ; 54(5): 1313-1315, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35717257

RESUMEN

BACKGROUND: Identifying anatomic variations of the hepatic artery is essential in liver transplantation. The artery supply is crucial for the procedure's success, and, in some cases of anatomic variations, they need reconstruction. Hepatic artery thrombosis is a severe vascular complication. This study evaluated the prevalence of anatomic variations and correlated arterial reconstructions with hepatic artery thrombosis. METHODS: We performed a retrospective analysis of medical records, adult patients undergoing liver transplant, donor's arterial anatomy, arterial reconstructions, and thrombosis after transplant from January 2019 to December 2020. RESULTS: Among 226 cases, 71% had normal anatomy. All these patients met Michel's classification subtypes, of which 161 (71%) were class I, which is the most common. The second most common variation was class II, with 25 donors (11%), followed by class III, with 17 donors (7.5%). Anatomic artery variations were a risk factor for hepatic artery thrombosis development (odds ratio [OR], 7.2; 95% confidence interval [CI], 2.1-22.5; P = .002). In the same way, the artery reconstruction was associated with hepatic artery thrombosis arising with postoperative time (OR, 18.0; 95% CI, 4.9-57.5; P < .001). Global hepatic artery thrombosis occurred in 11 cases (4.87%). CONCLUSION: Anatomic hepatic artery variations are frequent and do not make liver transplant unfeasible. However, variations that require reconstruction may raise the risk of thrombosis.


Asunto(s)
Hepatopatías , Trasplante de Hígado , Trombosis , Adulto , Arteria Hepática/cirugía , Humanos , Hepatopatías/complicaciones , Trasplante de Hígado/efectos adversos , Prevalencia , Estudios Retrospectivos , Trombosis/epidemiología , Trombosis/etiología
16.
Transplant Proc ; 54(5): 1352-1356, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35715360

RESUMEN

BACKGROUND: The small-for-size syndrome (SFSS) is characterized by prolonged hyperbilirubinemia, coagulopathy, and/or encephalopathy caused by a small liver graft that cannot sustain the metabolic demands of the recipient after a partial liver transplant (PLT). Models of PLT in pigs are excellent for studying this syndrome. This review aimed to identify the different porcine models of SFSS in the literature and compare their technical aspects and therapeutics methods focused on portal inflow modulation (PIM). METHODS: We performed a systematic review of the porcine experimental model and SFSS. The MEDLINE-PubMed, EMBASE, Cochrane Library, LILACS, and SciELO databases were electronically searched and updated until June 20, 2021. The MeSH terms used were ''ORGAN SIZE'' AND ''LIVER TRANSPLANTATION". RESULTS: Thirteen SFSS porcine models were reported. Four were performed with portocaval shunt to PIM and 3 with mesocaval shunt to PIM. A few studies focused on clinical therapeutics to PIM; a study described somatostatin infusion to avoid SFSS. Initially, studies on PIM showed its potentially beneficial effects without mentioning the minimum portal flow that permits liver regeneration. However, an excessive portal diversion could be detrimental to this process. CONCLUSIONS: The use of porcine models on SFSS resulted in a better understanding of its pathophysiology and led to the establishment of various types of portal modulation, surgical techniques with different complexities, and pharmaceutical strategies such as somatostatin, making clear that without reducing the portal vein pressure the outcomes are poor. With the improvement of these techniques, SFSS can be avoided.


Asunto(s)
Trasplante de Hígado , Animales , Regeneración Hepática/fisiología , Trasplante de Hígado/efectos adversos , Trasplante de Hígado/métodos , Donadores Vivos , Modelos Teóricos , Derivación Portocava Quirúrgica , Presión Portal/fisiología , Vena Porta/cirugía , Somatostatina , Porcinos , Síndrome
17.
Transplant Proc ; 54(5): 1357-1360, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35717258

RESUMEN

BACKGROUND: Liver transplantation in an animal model is challenging due to hemodynamics and intraoperative anesthetic care. Several models are described in the literature employing different techniques such as venovenous bypass or aortic cross-clamping to maintain hemodynamic stability, although few groups keep the animal alive in the postoperative period. This study aims to evaluate a liver transplantation clinical model in pigs without venovenous bypass or aortic cross-clamping. METHODS: Male pigs weighing 20 to 35 kg underwent liver transplantation surgery without using venovenous bypass or aorta cross-clamping. Protocols were approved by the Animal Care and Use Committee of the University of São Paulo, Brazil. RESULTS: Ten LTs were performed. Cold ischemia and warm ischemia were 119 ± 33.28 minutes and 26 ± 9.6 minutes, respectively. Hemodynamic changes were significantly higher after the postrevasculazation phase: heart rate (P < .001), medium arterial pressure (P < .001), and cardiac output (P = .03). Hypotension was treated with intravenous fluids and, in some cases, with vasoactive drugs especially during the post-reperfusion period. No animals died during the procedure and almost survival until the first postoperative day. Serum aspartate aminotransferase and lactate increased their values in the post-reperfusion phase. CONCLUSIONS: Practice-based on laboratory animals improves surgical skills and the development of experimental models aimed at new advances in this field. Perfecting our technique on the swine model, we could move forward to create a small-for-size model, test new therapeutic strategies, and define the boundaries for safely performing an enlarged liver resection or a partial liver graft transplant.


Asunto(s)
Trasplante de Hígado , Animales , Hemodinámica , Hígado/cirugía , Trasplante de Hígado/métodos , Masculino , Modelos Teóricos , Porcinos , Isquemia Tibia
18.
Surgery ; 169(6): 1512-1518, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33678500

RESUMEN

BACKGROUND: Liver ischemia reperfusion injury is still an unsolved problem in liver surgery and transplantation. In this setting, hypothermia is the gold standard method for liver preservation for transplantation. Hypertonic saline solution reduces inflammatory response with better hemodynamic recovery in several situations involving ischemia reperfusion injury. Here, we investigated the effect of hypertonic saline solution in hypothermic liver submitted to ischemia reperfusion injury. METHODS: Fifty male rats were divided into 5 groups: SHAM, WI (animals submitted to 40 minutes of partial warm liver ischemia and reperfusion), HI (animals submitted to 40 minutes hypothermic ischemia), HSPI (animals submitted to hypothermic ischemia and treated with 7.5% hypertonic saline solution preischemia), and HSPR (animals submitted to hypothermic ischemia and treated with hypertonic saline solution previously to liver reperfusion). Four hours after reperfusion, the animals were euthanized to collect liver and blood samples. RESULTS: Aspartate aminotransferase and alanine aminotransferase, histologic score, and hepatocellular necrosis were significantly decreased in animals submitted to hypothermia compared with the warm ischemia group. Malondialdehyde was significantly decreased in hypothermic groups with a further decrease when hypertonic saline solution was administrated preischemia. Hypothermic groups also showed decreased interleukin-6, interleukin-10, and tumor necrosis factor-α concentrations and better recovery of bicarbonate, base excess, lactate, and glucose blood concentrations. Moreover, hypertonic saline solution preischemia was more effective at controlling serum potassium concentrations. CONCLUSION: Hypertonic saline solution before hypothermic hepatic ischemia decreases hepatocellular oxidative stress, cytokine concentrations, and promotes better recovery of acid-base disorders secondary to liver ischemia reperfusion.


Asunto(s)
Hepatopatías/prevención & control , Estrés Oxidativo/efectos de los fármacos , Daño por Reperfusión/prevención & control , Solución Salina Hipertónica/uso terapéutico , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Glucemia/análisis , Hipotermia Inducida/métodos , Peroxidación de Lípido/efectos de los fármacos , Masculino , Ratas , Ratas Wistar
19.
Xenotransplantation ; 17(6): 423-8, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21192494

RESUMEN

INTRODUCTION: Xenotransplantation and multivisceral transplantation are advanced therapeutic methods that still require a scientific basis. There are no experimental models of multivisceral transplantation available, particularly not the monitoring by endoscopy. Here, we describe the endoscopic features in a model of multivisceral xenotransplantation. METHODS: The distal esophagus, stomach, intestine, colon, liver, pancreas, and the kidneys with a common vascular pedicle were harvested from rabbits and implanted in swine (group I, n = 9) or in rabbits (group II, n = 4). Endoscopy was performed in the stomach, jejunum, and ascending colon at four consecutive time points (immediate after surgery and 10, 90, and 180 min after reperfusion). Lesions were macroscopically graded as mild, moderate, and severe. Biopsies were taken following sacrifice at 180 min after reperfusion. RESULTS: In group I, the stomach, jejunum, and colon manifested a progression of lesions with predominance of mild lesions after 10 min, mild to moderate lesions after 90 min, and moderate to severe lesions after 180 min. In animals from group II, endoscopy showed normal features at all time points after reperfusion. Histopathologic analysis confirmed the diagnosis of hyperacute rejection in group I. Grafts from group II animals presented normal or mild ischemic/reperfusion injury. CONCLUSION: All animals subjected to multivisceral xenotransplantation showed a progression of endoscopic lesions with time after transplantation, while animals subjected to allotransplantation showed no aberrations in endoscopy. We conclude that endoscopy is a useful tool in the assessment of hyperacute rejection of a xenograft.


Asunto(s)
Trasplante Heterólogo/métodos , Vísceras/trasplante , Animales , Endoscopía Gastrointestinal , Rechazo de Injerto/patología , Humanos , Conejos , Porcinos , Trasplante Heterólogo/patología , Vísceras/patología
20.
Rev Assoc Med Bras (1992) ; 55(4): 489-96, 2009.
Artículo en Portugués | MEDLINE | ID: mdl-19750320

RESUMEN

The accumulation of free fluid of pathological origin in the peritoneal cavity is named ascites, and, in clinical practice this phenomenon is present in several diseases. The most common cause of ascites is liver cirrhosis. In the pathophysiology of ascites three theories are noteworthy: vasodilation, overflow and underfill. The modern concept suggest that these three theories are present in the same patient with cirrhosis depending on the disease evolution time. The vasodilation theory would be important in the pre-ascitic phase as well as during all the ascites evolution time. The overflow theory would be important in the first months of development of ascites in cirrhosis, and the underfill theory would explain most of the findings in patients with ascites for a long time. This article comments in detailed, several diseases that produce ascites, the diagnostic methods employed in clinical investigation of ascites' complication and therapeutics options available. In each item the evidence grade (A to C) found in medical literature is shown.


Asunto(s)
Ascitis , Medicina Basada en la Evidencia , Ascitis/diagnóstico , Ascitis/etiología , Ascitis/terapia , Humanos , Cirrosis Hepática/complicaciones
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