Meindert N. Sosef
University of Amsterdam
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BMC Surgery | 2010
Hilko A Swank; J. Vermeulen; Johan F. Lange; Irene M. Mulder; Joost A. B. van der Hoeven; Laurents P. S. Stassen; Rogier Mph Crolla; Meindert N. Sosef; Simon W. Nienhuijs; Robbert J. I. Bosker; Maarten J Boom; Philip M Kruyt; Dingeman J. Swank; Willem H. Steup; Eelco J. R. de Graaf; Wibo F. Weidema; Robert E. G. J. M. Pierik; Hubert A. Prins; H. B. A. C. Stockmann; Rob A. E. M. Tollenaar; Bart A. van Wagensveld; Peter-Paul Coene; Gerrit D. Slooter; E. C. J. Consten; Eino B van Duijn; Michael F. Gerhards; Anton G M Hoofwijk; Thomas Karsten; Peter Neijenhuis; Charlotte F J M Blanken-Peeters
BackgroundRecently, excellent results are reported on laparoscopic lavage in patients with purulent perforated diverticulitis as an alternative for sigmoidectomy and ostomy.The objective of this study is to determine whether LaparOscopic LAvage and drainage is a safe and effective treatment for patients with purulent peritonitis (LOLA-arm) and to determine the optimal resectional strategy in patients with a purulent or faecal peritonitis (DIVA-arm: perforated DIVerticulitis: sigmoidresection with or without Anastomosis).Methods/DesignIn this multicentre randomised trial all patients with perforated diverticulitis are included. Upon laparoscopy, patients with purulent peritonitis are treated with laparoscopic lavage and drainage, Hartmanns procedure or sigmoidectomy with primary anastomosis in a ratio of 2:1:1 (LOLA-arm). Patients with faecal peritonitis will be randomised 1:1 between Hartmanns procedure and resection with primary anastomosis (DIVA-arm). The primary combined endpoint of the LOLA-arm is major morbidity and mortality. A sample size of 132:66:66 patients will be able to detect a difference in the primary endpoint from 25% in resectional groups compared to 10% in the laparoscopic lavage group (two sided alpha = 5%, power = 90%). Endpoint of the DIVA-arm is stoma free survival one year after initial surgery. In this arm 212 patients are needed to significantly demonstrate a difference of 30% (log rank test two sided alpha = 5% and power = 90%) in favour of the patients with resection with primary anastomosis. Secondary endpoints for both arms are the number of days alive and outside the hospital, health related quality of life, health care utilisation and associated costs.DiscussionThe Ladies trial is a nationwide multicentre randomised trial on perforated diverticulitis that will provide evidence on the merits of laparoscopic lavage and drainage for purulent generalised peritonitis and on the optimal resectional strategy for both purulent and faecal generalised peritonitis.Trial registrationNederlands Trial Register NTR2037
BMC Surgery | 2011
Surya S. A. Y. Biere; K. W. Maas; Luigi Bonavina; Josep Roig Garcia; Mark I. van Berge Henegouwen; Camiel Rosman; Meindert N. Sosef; Elly S. M. de Lange; H. Jaap Bonjer; Miguel A. Cuesta; Donald L. van der Peet
BackgroundThere is a rise in incidence of esophageal carcinoma due to increasing incidence of adenocarcinoma. Probably the only curative option to date is the use of neoadjuvant therapy followed by surgical resection. Traditional open esophageal resection is associated with a high morbidity and mortality rate. Furthermore, this approach involves long intensive care unit stay, in-hospital stay and long recovery period. Minimally invasive esophagectomy could reduce the morbidity and accelerate the post-operative recovery.Methods/DesignComparison between traditional open and minimally invasive esophagectomy in a multi-center, randomized trial. Patients with a resectable intrathoracic esophageal carcinoma, including the gastro-esophageal junction tumors (Siewert I) are eligible for inclusion. Prior thoracic surgery and cervical esophageal carcinoma are indications for exclusion. The surgical technique involves a right thoracotomy with lung blockade and laparotomy either with a cervical or thoracic anastomosis for the traditional group. The minimally invasive procedure involves a right thoracoscopy in prone position with a single lumen tube and laparoscopy either with a cervical or thoracic anastomosis. All patients in both groups will undergo identical pre-operative and post-operative protocol. Primary endpoint of this study are post-operative respiratory complications within the first two post-operative weeks confirmed by clinical, radiological and sputum culture data. Secondary endpoints are the operative data, the post-operative data and oncological data such as quality of the specimen and survival. Operative data include duration of the operation, blood loss and conversion to open procedure. Post-operative data include morbidity (major and minor), quality of life tests and hospital stay.Based on current literature and the experience of all participating centers, an incidence of pulmonary complications for 57% in the traditional arm and 29% in the minimally invasive arm, it is estimated that per arm 48 patients are needed. This is based on a two-sided significance level (alpha) of 0.05 and a power of 0.80. Knowing that approximately 20% of the patients will be excluded, we will randomize 60 patients per arm.DiscussionThe TIME-trial is a prospective, multi-center, randomized study to define the role of minimally invasive esophageal resection in patients with resectable intrathoracic and junction esophageal cancer.Trial registration (Netherlands Trial Register)NTR2452
Transplantation | 2002
Meindert N. Sosef; Leo S. L. Abrahamse; Maarten-Paul van de Kerkhove; Robin Hartman; R.A.F.M. Chamuleau; Thomas M. van Gulik
Background. The anhepatic pig model was used to evaluate a bioartificial liver developed in our institution (AMC-BAL). The bioartificial liver is based on oxygenated plasma perfusion of porcine hepatocytes attached to a polyester matrix. Methods. Pigs (n=15) underwent total hepatectomy with restoration of caval continuity using a polyethylene, three-way prosthesis. In group I, pigs received limited intensive care under continuation of general anesthesia (n=5). Group II pigs (n=5) underwent, in addition, extracorporeal plasma perfusion of an AMC-BAL without hepatocytes (device control group). In group III (n=5), plasma perfusion occurred with an AMC-BAL loaded with autologous hepatocytes. Groups II and III were connected to the extracorporeal system 24 hr after hepatectomy, for a period of 24 hr. The main outcome parameters were as follows: survival time, liver enzymes (aspartate aminotransferase, alanine aminotransferase), blood ammonia, and total/direct bilirubin. Results. Survival (mean ± SD) of the anhepatic pigs was significantly increased in the BAL-treated group (group III: 65±15 hr), as compared with the control groups (group I: 46±6 hr and group II: 43±14 hr). Mean blood ammonia levels during BAL treatment were significantly lower in the BAL-treated group in comparison with both control groups (P =0.02). Total and direct bilirubin levels gradually increased after hepatectomy and reached maximum values of 1.98 mg/dl and 1.50 mg/dl, respectively, showing no differences between the three groups. Conclusions. (1) Treatment of anhepatic pigs with the AMC-BAL containing autologous hepatocytes significantly increases survival time, which is associated with a significant decrease in blood ammonia. 2) Anhepatic pigs demonstrate increasing direct bilirubin levels as a result of extrahepatic bilirubin conjugation.
Digestive Surgery | 2005
Suzanne S. Gisbertz; Meindert N. Sosef; Sebastiaan Festen; Michael F. Gerhards
Background: Recent publications show promising results using fibrin glue in the treatment of anal fistulas. The technique is simple, repeatable, with minor surgical trauma so that sphincter function is preserved and further treatment options are not compromised. The aim of this pilot study was to analyse if we could reproduce the results reported in the literature, using this simple technique. Methods: Patients with a primary or recurrent anal fistula were included in this trial. Patients with a complex fistula were excluded. Under general or spinal anaesthesia, the fistulas were curetted and injected with fibrin glue. Follow-up visits were scheduled for 1 week, 6 weeks and 6 months. Results: Twenty-seven patients were included. The overall success rate was 33% after a mean follow-up of 27 weeks. Patients with a recurrent fistula had a poorer outcome (success rate 14%). None of the patients suffered from postoperative continence problems, and no other complications were recorded. Conclusion: This study confirms the safety of fibrin glue in the treatment of anal fistulas. However, a high success rate could not be reproduced.
JMIR Research Protocols | 2015
Bo Jan Noordman; Joel Shapiro; Manon Spaander; Kausilia K. Krishnadath; Hanneke W. M. van Laarhoven; Mark I. van Berge Henegouwen; G.A.P. Nieuwenhuijzen; Richard van Hillegersberg; Meindert N. Sosef; Ewout W. Steyerberg; Bas P. L. Wijnhoven; J. Jan B. van Lanschot; Gja Offerhaus
Background Results from the recent CROSS trial showed that neoadjuvant chemoradiotherapy (nCRT) significantly increased survival as compared to surgery alone in patients with potentially curable esophageal cancer. Furthermore, in the nCRT arm 49% of patients with a squamous cell carcinoma (SCC) and 23% of patients with an adenocarcinoma (AC) had a pathologically complete response in the resection specimen. These results provide a rationale to reconsider and study the timing and necessity of esophagectomy in (all) patients after application of the CROSS regimen. Objective We propose a “surgery as needed” approach after completion of nCRT. In this approach, patients will undergo active surveillance after completion of nCRT. Surgical resection would be offered only to those patients in whom residual disease or a locoregional recurrence is highly suspected or proven. However, before a surgery as needed approach in oesophageal cancer patients (SANO) can be tested in a randomized controlled trial, we aim to determine the accuracy of detecting the presence or absence of residual disease after nCRT (preSANO trial). Methods This study is set up as a prospective, single arm, multicenter, diagnostic trial. Operable patients with potentially curable SCC or AC of the esophagus or esophagogastric junction will be included. Approximately 4-6 weeks after completion of nCRT all included patients will undergo a first clinical response evaluation (CRE-I) including endoscopy with (random) conventional mucosal biopsies of the primary tumor site and of any other suspected lesions in the esophagus and radial endo-ultrasonography (EUS) for measurement of tumor thickness and area. Patients in whom no locoregional or disseminated disease can be proven by cytohistology will be offered a postponed surgical resection 6-8 weeks after CRE-I (ie, approximately 12-14 weeks after completion of nCRT). In the week preceding the postponed surgical resection, a second clinical response evaluation (CRE-II) will be planned that will include a whole body PET-CT, followed again by endoscopy with (random) conventional mucosal biopsies of the primary tumor site and any other suspected lesions in the esophagus, radial EUS for measurement of tumor thickness and area, and linear EUS plus fine needle aspiration of PET-positive lesions and/or suspected lymph nodes. The main study parameter is the correlation between the clinical response assessment during CRE-I and CRE-II and the final pathological response in the resection specimen. Results The first patient was enrolled on July 23, 2013, and results are expected in January 2016. Conclusions If this preSANO trial shows that the presence or absence of residual tumor can be predicted reliably 6 or 12 weeks after completion of nCRT, a randomized trial comparing nCRT plus standard surgery versus chemoradiotherapy plus “surgery as needed” will be conducted (SANO trial). Trial Registration Netherlands Trial Register: NTR4834; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=4834 (archived by Webcite at http://www.webcitation.org/6Ze7mn67B).
BMC Surgery | 2008
Emma J. Eshuis; Willem A. Bemelman; Ad A. van Bodegraven; Mirjam A. G. Sprangers; Patrick M. Bossuyt; A. W. Marc van Milligen de Wit; Rogier Mph Crolla; Djuna L. Cahen; Liekele Oostenbrug; Meindert N. Sosef; Annet M. C. J. Voorburg; Paul H. P. Davids; C. Janneke van der Woude; Johan F. Lange; Rosalie C. Mallant; Maarten J Boom; Rob Lieverse; Edwin S. van der Zaag; Martin H. M. G. Houben; Juda Vecht; Robert E. G. J. M. Pierik; Theo J. van Ditzhuijsen; Hubert A. Prins; Willem A. Marsman; Henricus B. Stockmann; Menno A. Brink; E. C. J. Consten; Sjoerd D. J. van der Werf; Andreas W Marinelli; Jeroen M. Jansen
BackgroundWith the availability of infliximab, nowadays recurrent Crohns disease, defined as disease refractory to immunomodulatory agents that has been treated with steroids, is generally treated with infliximab. Infliximab is an effective but expensive treatment and once started it is unclear when therapy can be discontinued. Surgical resection has been the golden standard in recurrent Crohns disease. Laparoscopic ileocolic resection proved to be safe and is characterized by a quick symptom reduction.The objective of this study is to compare infliximab treatment with laparoscopic ileocolic resection in patients with recurrent Crohns disease of the distal ileum with respect to quality of life and costs.Methods/designThe study is designed as a multicenter randomized clinical trial including patients with Crohns disease located in the terminal ileum that require infliximab treatment following recent consensus statements on inflammatory bowel disease treatment: moderate to severe disease activity in patients that fail to respond to steroid therapy or immunomodulatory therapy. Patients will be randomized to receive either infliximab or undergo a laparoscopic ileocolic resection. Primary outcomes are quality of life and costs. Secondary outcomes are hospital stay, early and late morbidity, sick leave and surgical recurrence. In order to detect an effect size of 0.5 on the Inflammatory Bowel Disease Questionnaire at a 5% two sided significance level with a power of 80%, a sample size of 65 patients per treatment group can be calculated. An economic evaluation will be performed by assessing the marginal direct medical, non-medical and time costs and the costs per Quality Adjusted Life Year (QALY) will be calculated. For both treatment strategies a cost-utility ratio will be calculated. Patients will be included from December 2007.DiscussionThe LIR!C-trial is a randomized multicenter trial that will provide evidence whether infliximab treatment or surgery is the best treatment for recurrent distal ileitis in Crohns disease.Trial registrationNederlands Trial Register NTR1150
International Journal of Artificial Organs | 2002
Salomon L. Abrahamse; M.P. van de Kerkhove; Meindert N. Sosef; Robin Hartman; R.A.F.M. Chamuleau; T.M. van Gulik
Several different types of bioartificial liver (BAL) support systems have been developed to bridge patients suffering from acute liver failure (ALF) to transplantation or liver regeneration. In this study we assessed the effects of ALF plasma on hepatocyte function in the BAL system that has been developed in our center. Pigs (40–60 kg) were anaesthetised and a total hepatectomy was performed. Cells were isolated from the resected livers and were transferred to the bioreactor of the BAL system. Twenty hours after cell isolation, hepatocytes in the BAL were tested for cell viability and functional activity by using a recirculating test medium in which assessment of LDH leakage, ammonia clearance, urea synthesis, 7-ethoxycoumarin O-deethylase (ECOD) activity and pseudocholine esterase production was performed. Subsequently, two groups were studied. In one group (I, n=5), the cell-loaded bioreactor was used to treat the donor pig, rendered anhepatic, for 24 hours. In the second group (II, n=5) the bioreactor was cultured for 24 h and served as a control. After 24 hours treatment or culturing, the cell viability count and functional activity tests were repeated. The results show that hepatocytes in the BAL remained viable after 24 h treatment of anhepatic pigs, as shown by the LDH release and pseudocholine esterase production. However, metabolic functions such as ammonia clearance, ECOD and urea synthesis were reduced after 24 h exposure of hepatocytes to autologous ALF plasma, whereas these functions were unaltered after 24 h culturing of the cells in the bioreactor.
Journal of Thrombosis and Haemostasis | 2003
Meindert N. Sosef; M-P. Van De Kerkhove; Salomon L. Abrahamse; Marcel Levi; R.A.F.M. Chamuleau; T.M. van Gulik
Summary. The function of a newly devised bioartificial liver (AMC‐BAL) based on viable, freshly isolated porcine hepatocytes has been evaluated in anhepatic pigs. The aim of this study was to assess the contribution of BAL treatment on blood coagulation parameters. Pigs were anesthetized and a total hepatectomy was performed (n = 15). The infrahepatic caval vein and the portal vein were connected to the subdiaphragmatic caval vein using a three‐way prosthesis. Animals received standard intensive care (control, n= 5), treatment with an empty BAL (device control, n= 5) or with a cell‐loaded BAL (BAL‐treatment, n= 5) for a period of 24 h starting 24 h after hepatectomy. Coagulation parameters studied concerned prothrombin time (PT), platelet count, the procoagulant system (factors (F)II, FV, FVII, FVIII and fibrinogen), anticoagulant system (AT III), fibrinolytic system (t‐PA, PAI‐1) as well as markers of coagulation factor activation (TAT complexes, prothrombin fragment F1 + 2). FII, FV, FVII, AT III and fibrinogen rapidly decreased after total hepatectomy in pigs in accordance with the anhepatic state of the animals. FVIII levels were not influenced by the hepatectomy. A mild drop in platelet count was seen in all groups. Treatment of anhepatic pigs with the cell‐loaded BAL did not restore PT or clotting factor levels. TAT and F1 + 2 complexes, however, were significantly increased in this group. Levels of t‐PA and PAI‐1 were not influenced by cell‐loaded BAL treatment. Treatment of anhepatic pigs with the AMC‐BAL based on freshly isolated porcine hepatocytes does not result in an improved coagulation state due to extensive consumption of clotting factors. However, increased levels of TAT complexes and prothrombin fragments F1 + 2 during treatment of anhepatic pigs indicate synthesis and direct activation of coagulation factors, leading to thrombin generation. This demonstrates that this bioartificial liver is capable of synthesizing coagulation factors.
BMJ Open | 2014
Teus J. Weijs; G.A.P. Nieuwenhuijzen; Jelle P. Ruurda; Ewout A. Kouwenhoven; Camiel Rosman; Meindert N. Sosef; Richard van Hillegersberg; Misha D. Luyer
Introduction The best route of feeding for patients undergoing an oesophagectomy is unclear. Concerns exist that early oral intake would increase the incidence and severity of pneumonia and anastomotic leakage. However, in studies including patients after many other types of gastrointestinal surgery and in animal experiments, early oral intake has been shown to be beneficial and enhance recovery. Therefore, we aim to determine the feasibility of early oral intake after oesophagectomy. Methods and analysis This study is a feasibility trial in which 50 consecutive patients will start oral intake directly following oesophagectomy. Primary outcomes will be the frequency and severity of anastomotic leakage and (aspiration) pneumonia. Clinical parameters will be registered prospectively and nutritional requirements and intake will be assessed by a dietician. Surgical complications will be registered. Ethics and dissemination Approval for this study has been obtained from the Medical Ethical Committee of the Catharina Hospital Eindhoven and the study has been registered at the Dutch Trial Register, NTR4136. Results will be published and presented at international congresses. Discussion We hypothesise that the oral route of feeding is safe and feasible following oesophagectomy, as has been shown previously for other types of gastrointestinal surgery. It is expected that early oral nutrition will result in enhanced recovery. Furthermore, complications related to artificial feeding, such as jejunostomy tube feeding, are believed to be reduced. However, (aspiration) pneumonia and anastomotic leakage are potential risks that are carefully monitored. Trial registration number NTR4136.
European Surgical Research | 2004
Meindert N. Sosef; T.M. van Gulik
Total hepatectomy in animals provides an irreversible model of acute liver failure. Vascular reconstruction in this model of acute liver failure was modified and characterized for the use of assessment of liver support systems. Pigs underwent total hepatectomy and a rigid three-way transparent polyethylene vascular conduit was used to replace the retrohepatic caval vein and to shunt the portal venous blood to the caval vein. Placement of the vascular conduit in conjunction with excision of the liver was completed in 10–22 min without the need of a temporary veno-venous bypass. A survival study conducted in 5 animals showed a mean survival time of 46 ± 6 h. Baseline and 4 h postoperative hemoglobin levels were not different, and plasma ammonia levels rose to more than 30-fold of baseline values. All animals died of cardiac arrhythmias and irreversible shock. Total hepatectomy in the pig using a three-way portal-venous conduit is a reliable and well-reproducible animal model of acute liver failure for evaluation of liver assist devices.