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Jain R, Ajenu EO, Hafiz EOA, Romfh P, Tessier SN. Real-time monitoring of mitochondrial oxygenation during machine perfusion using resonance Raman spectroscopy predicts organ function. RESEARCH SQUARE 2023:rs.3.rs-3740098. [PMID: 38196624 PMCID: PMC10775389 DOI: 10.21203/rs.3.rs-3740098/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2024]
Abstract
Organ transplantation is a life-saving procedure affecting over 100,000 people on the transplant waitlist. Ischemia reperfusion injury is a major challenge in the field as it can cause post-transplantation complications and limits the use of organs from extended criteria donors. Machine perfusion technology is used to repair organs before transplant, however, currently fails to achieve its full potential due to a lack of highly sensitive and specific assays to predict organ quality during perfusion. We developed a real-time and non-invasive method of assessing organ function and injury based on mitochondrial oxygenation using resonance Raman spectroscopy. It uses a 441 nm laser and a high-resolution spectrometer to predict the oxidation state of mitochondrial cytochromes during perfusion, which vary due to differences in storage compositions and perfusate compositions. This index of mitochondrial oxidation, or 3RMR, was found to predict organ health based on clinically utilized markers of perfusion quality, tissue metabolism, and organ injury. It also revealed differences in oxygenation with perfusates that may or may not be supplemented with packed red blood cells as oxygen carriers. This study emphasizes the need for further refinement of a reoxygenation strategy during machine perfusion that is based on a gradual recovery from storage. Thus, we present a novel platform that provides a real-time and quantitative assessment of mitochondrial health during machine perfusion of livers, which is easy to translate to the clinic.
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Affiliation(s)
- Rohil Jain
- Harvard Medical School & Massachusetts General Hospital
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2
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Parente A, Flores Carvalho M, Schlegel A. Endothelial Cells and Mitochondria: Two Key Players in Liver Transplantation. Int J Mol Sci 2023; 24:10091. [PMID: 37373238 DOI: 10.3390/ijms241210091] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Revised: 05/30/2023] [Accepted: 06/02/2023] [Indexed: 06/29/2023] Open
Abstract
Building the inner layer of our blood vessels, the endothelium forms an important line communicating with deeper parenchymal cells in our organs. Previously considered passive, endothelial cells are increasingly recognized as key players in intercellular crosstalk, vascular homeostasis, and blood fluidity. Comparable to other cells, their metabolic function strongly depends on mitochondrial health, and the response to flow changes observed in endothelial cells is linked to their mitochondrial metabolism. Despite the direct impact of new dynamic preservation concepts in organ transplantation, the impact of different perfusion conditions on sinusoidal endothelial cells is not yet explored well enough. This article therefore describes the key role of liver sinusoidal endothelial cells (LSECs) together with their mitochondrial function in the context of liver transplantation. The currently available ex situ machine perfusion strategies are described with their effect on LSEC health. Specific perfusion conditions, including perfusion pressure, duration, and perfusate oxygenation are critically discussed considering the metabolic function and integrity of liver endothelial cells and their mitochondria.
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Affiliation(s)
- Alessandro Parente
- HPB and Transplant Unit, Department of Surgical Science, University of Rome Tor Vergata, 00133 Rome, Italy
- Division of Hepatobiliary and Liver Transplantation, Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul 05505, Republic of Korea
| | | | - Andrea Schlegel
- Department of Experimental and Clinical Medicine, University of Florence, 50121 Florence, Italy
- Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Centre of Preclinical Research, 20122 Milan, Italy
- Transplantation Center, Digestive Disease and Surgery Institute, Department of Immunity and Inflammation, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44106, USA
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Schuler MJ, Becker D, Mueller M, Bautista Borrego L, Mancina L, Huwyler F, Binz J, Hagedorn C, Schär B, Gygax E, Weisskopf M, Sousa Da Silva RX, Antunes Crisóstomo JM, Dutkowski P, Rudolf von Rohr P, Clavien PA, Tibbitt MW, Eshmuminov D, Hefti M. Observations and findings during the development of a subnormothermic/normothermic long-term ex vivo liver perfusion machine. Artif Organs 2023; 47:317-329. [PMID: 36106378 DOI: 10.1111/aor.14403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Revised: 08/24/2022] [Accepted: 08/26/2022] [Indexed: 02/03/2023]
Abstract
BACKGROUND Ex situliver machine perfusion at subnormothermic/normothermic temperature isincreasingly applied in the field of transplantation to store and evaluateorgans on the machine prior transplantation. Currently, various perfusionconcepts are in clinical and preclinical applications. Over the last 6 years ina multidisciplinary team, a novel blood based perfusion technology wasdeveloped to keep a liver alive and metabolically active outside of the bodyfor at least one week. METHODS Within thismanuscript, we present and compare three scenarios (Group 1, 2 and 3) we werefacing during our research and development (R&D) process, mainly linked tothe measurement of free hemoglobin and lactate in the blood based perfusate. Apartfrom their proven value in liver viability assessment (ex situ), these twoparameters are also helpful in R&D of a long-term liver perfusion machine and moreover supportive in the biomedical engineering process. RESULTS Group 1 ("good" liver on the perfusion machine) represents the best liver clearance capacity for lactate and free hemoglobin wehave observed. In contrast to Group 2 ("poor" liver on the perfusion machine), that has shown the worst clearance capacity for free hemoglobin. Astonishingly,also for Group 2, lactate is cleared till the first day of perfusion andafterwards, rising lactate values are detected due to the poor quality of theliver. These two perfusate parametersclearly highlight the impact of the organ quality/viability on the perfusion process. Whereas Group 3 is a perfusion utilizing a blood loop only (without a liver). CONCLUSION Knowing the feasible ranges (upper- and lower bound) and the courseover time of free hemoglobin and lactate is helpful to evaluate the quality ofthe organ perfusion itself and the maturity of the developed perfusion device. Freehemoglobin in the perfusate is linked to the rate of hemolysis that indicates how optimizing (gentle blood handling, minimizing hemolysis) the perfusion machine actually is. Generally, a reduced lactate clearancecapacity can be an indication for technical problems linked to the blood supplyof the liver and therefore helps to monitor the perfusion experiments.Moreover, the possibility is given to compare, evaluate and optimize developed liverperfusion systems based on the given ranges for these two parameters. Otherresearch groups can compare/quantify their perfusate (blood) parameters withthe ones in this manuscript. The presented data, findings and recommendations willfinally support other researchers in developing their own perfusion machine ormodifying commercially availableperfusion devices according to their needs.
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Affiliation(s)
- Martin J Schuler
- Wyss Zurich - ETH Zurich/University of Zurich, Zurich, Switzerland
| | - Dustin Becker
- Wyss Zurich - ETH Zurich/University of Zurich, Zurich, Switzerland
| | - Matteo Mueller
- Department of Surgery, Swiss Hepato-Pancreato-Biliary and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | - Lucia Bautista Borrego
- Department of Surgery, Swiss Hepato-Pancreato-Biliary and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | - Leandro Mancina
- Department of Surgery, Swiss Hepato-Pancreato-Biliary and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | - Florian Huwyler
- Macromolecular Engineering Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, Switzerland
| | - Jonas Binz
- Wyss Zurich - ETH Zurich/University of Zurich, Zurich, Switzerland
| | - Catherine Hagedorn
- Department of Surgery, Swiss Hepato-Pancreato-Biliary and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | - Beatrice Schär
- Entwicklung biomedizinische Anwendungen, Securecell AG, Urdorf, Switzerland
| | - Erich Gygax
- Forschung und Entwicklung, Fumedica AG, Muri, Switzerland
| | - Miriam Weisskopf
- Center of Surgical Research, University Hospital Zürich, University of Zürich, Zurich, Switzerland
| | - Richard Xavier Sousa Da Silva
- Department of Surgery, Swiss Hepato-Pancreato-Biliary and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | | | - Philipp Dutkowski
- Department of Surgery, Swiss Hepato-Pancreato-Biliary and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | - Philipp Rudolf von Rohr
- Transport Processes and Reactions Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, Switzerland
| | - Pierre-Alain Clavien
- Department of Surgery, Swiss Hepato-Pancreato-Biliary and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | - Mark W Tibbitt
- Macromolecular Engineering Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, Switzerland
| | - Dilmurodjon Eshmuminov
- Department of Surgery, Swiss Hepato-Pancreato-Biliary and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | - Max Hefti
- Wyss Zurich - ETH Zurich/University of Zurich, Zurich, Switzerland
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Lascaris B, Thorne AM, Lisman T, Nijsten MWN, Porte RJ, de Meijer VE. Long-term normothermic machine preservation of human livers: what is needed to succeed? Am J Physiol Gastrointest Liver Physiol 2022; 322:G183-G200. [PMID: 34756122 DOI: 10.1152/ajpgi.00257.2021] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Although short-term machine perfusion (≤24 h) allows for resuscitation and viability assessment of high-risk donor livers, the donor organ shortage might be further remedied by long-term perfusion machines. Extended preservation of injured donor livers may allow reconditioning, repairing, and regeneration. This review summarizes the necessary requirements and challenges for long-term liver machine preservation, which requires integrating multiple core physiological functions to mimic the physiological environment inside the body. A pump simulates the heart in the perfusion system, including automatically controlled adjustment of flow and pressure settings. Oxygenation and ventilation are required to account for the absence of the lungs combined with continuous blood gas analysis. To avoid pressure necrosis and achieve heterogenic tissue perfusion during preservation, diaphragm movement should be simulated. An artificial kidney is required to remove waste products and control the perfusion solution's composition. The perfusate requires an oxygen carrier, but will also be challenged by coagulation and activation of the immune system. The role of the pancreas can be mimicked through closed-loop control of glucose concentrations by automatic injection of insulin or glucagon. Nutrients and bile salts, generally transported from the intestine to the liver, have to be supplemented when preserving livers long term. Especially for long-term perfusion, the container should allow maintenance of sterility. In summary, the main challenge to develop a long-term perfusion machine is to maintain the liver's homeostasis in a sterile, carefully controlled environment. Long-term machine preservation of human livers may allow organ regeneration and repair, thereby ultimately solving the shortage of donor livers.
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Affiliation(s)
- Bianca Lascaris
- Section of Hepatopancreatobiliary Surgery & Liver Transplantation, Department of Surgery, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Adam M Thorne
- Section of Hepatopancreatobiliary Surgery & Liver Transplantation, Department of Surgery, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Ton Lisman
- Surgical Research Laboratory, Department of Surgery, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Maarten W N Nijsten
- Department of Critical Care, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Robert J Porte
- Section of Hepatopancreatobiliary Surgery & Liver Transplantation, Department of Surgery, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Vincent E de Meijer
- Section of Hepatopancreatobiliary Surgery & Liver Transplantation, Department of Surgery, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
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Eshmuminov D, Hefti M, Mueller M, Schuler MJ, Bautista Borrego L, Schneider MA, Koch K, Weisskopf M, Tibbitt MW, Dutkowski P, Rudolf von Rohr P, Studt JD, Becker D, Clavien PA. Synthesis of coagulation factors during long-term ex situ liver perfusion. Artif Organs 2021; 46:273-280. [PMID: 34287985 DOI: 10.1111/aor.14041] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 06/10/2021] [Accepted: 07/06/2021] [Indexed: 01/04/2023]
Abstract
Robust viability assessment of grafts during normothermic liver perfusion is a prerequisite for organ use. Coagulation parameters are used commonly for liver assessment in patients. However, they are not yet included in viability assessment during ex situ perfusion. In this study, we analysed coagulation parameters during one week ex situ perfusion at 34℃. Eight discarded human livers were perfused with blood-based, heparinised perfusate for one week; perfusions in a further four livers were terminated on day 4 due to massive ongoing cell death. Coagulation parameters were well below the physiologic range at perfusion start. Physiologic levels were achieved within the first two perfusion days for factor V (68.5 ± 35.5%), factor VII (83.5 ± 26.2%), fibrinogen (2.1 ± 0.4 g/L) and antithrombin (107 ± 26.5%) in the livers perfused for one week. Despite the increased production of coagulation factors, INR was detectable only at 24h of perfusion (2.1 ± 0.3) and prolonged thereafter (INR > 9). The prolongation of INR was related to the high heparin level in the perfusate (anti-FXa > 3 U/mL). Intriguingly, livers with ongoing massive cell death also disclosed synthesis of factor V and improved INR. In summary, perfused livers were able to produce coagulation factors at a physiological level ex situ. We propose that single coagulation factor analysis is more reliable for assessing the synthetic function of perfused livers as compared to INR when using a heparinised perfusate.
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Affiliation(s)
- Dilmurodjon Eshmuminov
- Department of Surgery, Swiss Hepato-Pancreato-Biliary and Transplantation Center, University Hospital Zurich, Zurich, Switzerland.,Wyss Zurich - ETH Zurich/University of Zurich, Zurich, Switzerland
| | - Max Hefti
- Wyss Zurich - ETH Zurich/University of Zurich, Zurich, Switzerland.,Transport Processes and Reactions Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, Switzerland
| | - Matteo Mueller
- Department of Surgery, Swiss Hepato-Pancreato-Biliary and Transplantation Center, University Hospital Zurich, Zurich, Switzerland.,Wyss Zurich - ETH Zurich/University of Zurich, Zurich, Switzerland
| | - Martin J Schuler
- Wyss Zurich - ETH Zurich/University of Zurich, Zurich, Switzerland.,Transport Processes and Reactions Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, Switzerland
| | - Lucia Bautista Borrego
- Department of Surgery, Swiss Hepato-Pancreato-Biliary and Transplantation Center, University Hospital Zurich, Zurich, Switzerland.,Wyss Zurich - ETH Zurich/University of Zurich, Zurich, Switzerland
| | - Marcel André Schneider
- Department of Surgery, Swiss Hepato-Pancreato-Biliary and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | - Karin Koch
- Department of Medical Oncology and Hematology, University Hospital Zurich, Zurich, Switzerland
| | - Miriam Weisskopf
- Center of Surgical Research, University Hospital Zürich University of Zürich, Zurich, Switzerland
| | - Mark W Tibbitt
- Macromolecular Engineering Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, Switzerland
| | - Philipp Dutkowski
- Department of Surgery, Swiss Hepato-Pancreato-Biliary and Transplantation Center, University Hospital Zurich, Zurich, Switzerland
| | - Philipp Rudolf von Rohr
- Wyss Zurich - ETH Zurich/University of Zurich, Zurich, Switzerland.,Transport Processes and Reactions Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, Switzerland
| | - Jan-Dirk Studt
- Department of Medical Oncology and Hematology, University Hospital Zurich, Zurich, Switzerland
| | - Dustin Becker
- Wyss Zurich - ETH Zurich/University of Zurich, Zurich, Switzerland.,Transport Processes and Reactions Laboratory, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, Switzerland
| | - Pierre-Alain Clavien
- Department of Surgery, Swiss Hepato-Pancreato-Biliary and Transplantation Center, University Hospital Zurich, Zurich, Switzerland.,Wyss Zurich - ETH Zurich/University of Zurich, Zurich, Switzerland
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Orita E, Becker D, Mueller M, Hefti M, Schuler MJ, Bautista Borrego L, Dutkowski P, Zeimpekis K, Treyer V, Kaufmann PA, Eshmuminov D, Clavien PA, Huellner MW. FDG-PET/CT: novel method for viability assessment of livers perfused ex vivo. Nucl Med Commun 2021; 42:826-832. [PMID: 33741853 DOI: 10.1097/mnm.0000000000001399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE Ex vivo liver machine perfusion is a promising option to rescue marginal liver grafts mitigating the donated organ shortage. Recently, a novel liver perfusion machine that can keep injured liver grafts alive for 1 week ex vivo was developed and reported in Nature Biotechnology. However, liver viability assessment ex vivo is an unsolved issue and the value of 18F-fluorodeoxyglucose (FDG)-PET/CT for such purpose was explored. MATERIALS AND METHODS Discarded two human and six porcine liver grafts underwent FDG-PET/CT for viability assessment after 1 week of ex vivo perfusion. PET parameters [standardized uptake value (SUV)max, SUVmean, SUVpeak and total lesion glycolysis] were compared between hepatic lobes and between porcine and human livers. The prevalence of FDG-negative organ parts was recorded. The estimated effective radiation dose for PET/CT was calculated. RESULTS All organs were viable with essentially homogeneous FDG uptake. Of note, viability was preserved in contact areas disclosing the absence of pressure necrosis. Four porcine and two human organs had small superficial FDG-negative areas confirmed as biopsy sites. Total lesion glycolysis was significantly higher in the right hepatic lobe (P = 0.012), while there was no significant difference of SUVmax, SUVmean and SUVpeak between hepatic lobes. There was no significant difference in FDG uptake parameters between porcine and human organs. The estimated effective radiation dose was 1.99 ± 1.67 mSv per organ. CONCLUSION This study demonstrates the feasibility of FDG-PET/CT for viability assessment of ex vivo perfused liver grafts after 1 week.
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Affiliation(s)
- Erika Orita
- Department of Nuclear Medicine, University Hospital of Zurich, University of Zurich
| | - Dustin Becker
- Wyss Zurich, ETH Zurich and University of Zurich
- Transport Processes and Reactions Laboratory, Department of Mechanical and Process Engineering, ETH Zurich
| | - Matteo Mueller
- Wyss Zurich, ETH Zurich and University of Zurich
- Department of Surgery & Transplantation, Swiss Hepato-Pancreato-Biliary (HPB) Center, University Hospital of Zurich, University of Zurich, Zurich, Switzerland
| | - Max Hefti
- Wyss Zurich, ETH Zurich and University of Zurich
- Transport Processes and Reactions Laboratory, Department of Mechanical and Process Engineering, ETH Zurich
| | - Martin J Schuler
- Wyss Zurich, ETH Zurich and University of Zurich
- Transport Processes and Reactions Laboratory, Department of Mechanical and Process Engineering, ETH Zurich
| | - Lucia Bautista Borrego
- Wyss Zurich, ETH Zurich and University of Zurich
- Department of Surgery & Transplantation, Swiss Hepato-Pancreato-Biliary (HPB) Center, University Hospital of Zurich, University of Zurich, Zurich, Switzerland
| | - Philipp Dutkowski
- Wyss Zurich, ETH Zurich and University of Zurich
- Department of Surgery & Transplantation, Swiss Hepato-Pancreato-Biliary (HPB) Center, University Hospital of Zurich, University of Zurich, Zurich, Switzerland
| | | | - Valerie Treyer
- Department of Nuclear Medicine, University Hospital of Zurich, University of Zurich
| | - Philipp A Kaufmann
- Department of Nuclear Medicine, University Hospital of Zurich, University of Zurich
| | - Dilmurodjon Eshmuminov
- Wyss Zurich, ETH Zurich and University of Zurich
- Department of Surgery & Transplantation, Swiss Hepato-Pancreato-Biliary (HPB) Center, University Hospital of Zurich, University of Zurich, Zurich, Switzerland
| | - Pierre-Alain Clavien
- Department of Surgery & Transplantation, Swiss Hepato-Pancreato-Biliary (HPB) Center, University Hospital of Zurich, University of Zurich, Zurich, Switzerland
| | - Martin W Huellner
- Department of Nuclear Medicine, University Hospital of Zurich, University of Zurich
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Bile formation in long-term ex situ perfused livers. Surgery 2021; 169:894-902. [PMID: 33422346 DOI: 10.1016/j.surg.2020.11.042] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 11/18/2020] [Accepted: 11/27/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND Long-term ex situ liver perfusion may rescue injured grafts. Little is known about bile flow during long-term perfusion. We report the development of a bile stimulation protocol and motivate bile flow as a viability marker during long-term ex situ liver perfusion. METHODS Porcine and human livers were perfused with blood at close to physiologic conditions. Our perfusion protocol was established during phase 1 with porcine livers (n = 23). Taurocholic acid was applied to stimulate bile flow. The addition of piperacillin-tazobactam (tazobac) and methylprednisolone was modified from daily bolus to controlled continuous application. We adapted the protocol to human livers (n = 12) during phase 2. Taurocholic acid was replaced with medical grade ursodeoxycholic acid. RESULTS Phase 2: Despite administering taurocholic acid, bile flow declined from 29.3 ± 6.5 to 9.3 ± 1.4 mL/h (P < .001). Shortly after bolus of tazobac/methylprednisolone, bile flow recovered to 39.0 ± 9.7 mL/h with a decrease of solid bile components. This implied bile salt independent bile flow stimulation by tazobac/methylprednisolone. Phase 2: Ursodeoxycholic acid was shown to stimulate bile flow ex situ in human livers. Eight livers were perfused successfully for 1 week with continuous bile flow. The other 4 livers demonstrated progressive cell death, of which only 1 exhibited bile flow. CONCLUSION A lack of bile flow stimulation leads to a decline in bile flow and is not necessarily a sign of deterioration in liver function. Proper administration of stimulators can induce constant bile flow during ex situ liver perfusion for up to 1 week. Medical grade ursodeoxycholic acid is a suitable replacement for nonmedical grade taurocholic acid. The presence of bile flow alone is not sufficient to assess liver viability.
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