Knut Helmke
University of Hamburg
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Annals of Surgery | 2001
Dieter C. Broering; Lars Mueller; Rainer Ganschow; Jong-Sun Kim; Eike Achilles; Hansjörg Schäfer; Matthias Gundlach; Lutz Fischer; Martina Sterneck; Christian Hillert; Knut Helmke; Jacob R. Izbicki; Martin Burdelski; Xavier Rogiers
ObjectiveTo assess and compare the value of split-liver transplantation (SLT) and living-related liver transplantation (LRT). Summary Background DataThe concept of SLT results from the development of reduced-size transplantation. A further development of SLT, the in situ split technique, is derived from LRT, which itself marks the optimized outcome in terms of postoperative graft function and survival. The combination of SLT and LRT has abolished deaths on the waiting list, thus raising the question whether living donor liver transplantation is still necessary. MethodsOutcomes and postoperative liver function of 43 primary LRT patients were compared with those of 49 primary SLT patients (14 ex situ, 35 in situ) with known graft weight performed between April 1996 and December 2000. Survival rates were analyzed using the Kaplan-Meier method. ResultsAfter a median follow-up of 35 months, actual patient survival rates were 82% in the SLT group and 88% in the LRT group. Actual graft survival rates were 76% and 81%, respectively. The incidence of primary nonfunction was 12% in the SLT group and 2.3% in the LRT group. Liver function parameters (prothrombin time, factor V, bilirubin clearance) and surgical complication rates did not differ significantly. In the SLT group, mean cold ischemic time was longer than in the LRT group. Serum values of alanine aminotransferase during the first postoperative week were significantly higher in the SLT group. In the LRT group, there were more grafts with signs of fatty degeneration than in the SLT group. ConclusionsThe short- and long-term outcomes after LRT and SLT did not differ significantly. To avoid the risk for the donor in LRT, SLT represents the first-line therapy in pediatric liver transplantation in countries where cadaveric organs are available. LRT provides a solution for urgent cases in which a cadaveric graft cannot be found in time or if the choice of the optimal time point for transplantation is vital.
Annals of Surgery | 2004
Dieter C. Broering; Jong-Sun Kim; T Mueller; Lutz Fischer; Rainer Ganschow; Turan Bicak; Lars Mueller; Christian Hillert; Christian Wilms; Bernd Hinrichs; Knut Helmke; Werner Pothmann; Martin Burdelski; Xavier Rogiers
Objective:Orthotopic liver transplantation (OLT) has become an established procedure for the treatment of pediatric patients with end-stage liver disease. Since starting our program in 1989, 422 pediatric OLTs have been performed using all techniques presently available. Analyzing our series, we have concluded that the year of transplantation is the most important prognostic factor in patient and graft survival in a multivariate analysis. Methods:From April 2001 to December 1, 2003, 18 whole organs (14%), 17 reduced-size organs (13%), 53 split organs (42%; 46 ex situ, 7 in situ), and 44 organs from living donors (33%) were transplanted into 115 patients (62 male and 53 female). One hundred twelve were primary liver transplants, 18 were retransplants, one third and one fourth liver transplants. Of the 132 OLTs, 26 were highly urgent (19.7%). The outcome of these 132 OLTs was retrospectively analyzed. Results:Of 132 consecutive pediatric liver transplants, no patients died within the 6 months posttransplantation. Overall, 3 recipients (2%) died during further follow-up, 1 child because of severe pneumonia 13 months after transplantation and the second recipient with unknown cause 7 months postoperatively, both with good functioning grafts after uneventful transplantation. The third had a recurrence of an unknown liver disease 9 months after transplantation. The 3-month and actual graft survival rates are 92% and 86%, respectively. Sixteen children (12%) had to undergo retransplantation, the causes of which were chronic rejection (3.8%), primary nonfunction (3.8%), primary poor function (PPF; 1.5%), and arterial thrombosis (3%). The biliary complication rate was 6%; arterial complications occurred in 8.3%; intestinal perforation was observed in 3%; and in 5%, postoperative bleeding required reoperation. The portal vein complication rate was 2%. Conclusions:Progress during the past 15 years has enabled us to perform pediatric liver transplantation with near perfect patient survival. Advances in posttransplant care of the recipients, technical refinements, standardization of surgery and monitoring, and adequate choice of the donor organ and transplantation technique enable these results, which mark a turning point at which immediate survival after transplantation will be considered the norm. The long-term treatment of the transplanted patient, with the aim of avoiding late graft loss and achieving optimal quality of life, will become the center of debate.
Annals of Surgery | 2008
Christian Wilms; Lars Mueller; C Lenk; Oliver Wittkugel; Knut Helmke; Gerrit Krupski-Berdien; Xavier Rogiers; Dieter C. Broering
Summary Background Data:The extent of hepatectomies is limited by the functional reserve of the remnant liver. The introduction of preoperative portal vein occlusion techniques to induce a preoperative hyperplasia of the future liver remnant has reduced the risk of postoperative liver failure. However, it has remained a matter of debate whether partial portal vein embolization (PVE) or suture ligation of the portal branches during exploration is the preferred technique. We compared both techniques under standardized experimental conditions in a large animal model by means of effectiveness and pathophysiologic differences. Methods:Thirteen mini-pigs underwent portal vein ligation (PVL), 11 mini-pigs underwent PVE of 75% of the liver volume, and 6 underwent a sham operation. The animals were killed after 28 days. Laboratory liver function and damage parameters, lobar liver-to-body weight indices, portal and arterial flow alterations, and histologic changes were assessed. Ex situ arteriograms and portograms were performed to examine adaptive changes in the macroarchitecture of both vascular systems. Results:The liver-to-body weight index of the nonoccluded lobe was highest after PVE (0.85) versus 0.6 (P < 0.05) after PVL. There was no significant reduction in global serum parameters reflecting total liver function. After 4 weeks, the PVL group consistently exhibited hepatopetal portal flow in the ligated lobes, which was present but significantly decreased after PVE. The ex situ angiography after PVE and PVL revealed the development of portal neocollaterals in the portal-occluded liver parts. Conclusions:Both PVL and PVE are able to induce hypertrophy of the future liver remnant. In comparison, PVE is the more effective technique to increase the future liver remnant. This is due to a more effective, durable occlusion of the portal branches. Formation of collaterals between occluded and nonoccluded liver parts seems to be the cause of inferior regeneration in the ligation group.
Acta Ophthalmologica | 2011
Hans-Christian Hansen; Wolf A. Lagrèze; Oswald Krueger; Knut Helmke
Purpose: To determine the distensibility and elastic characteristics of the optic nerve sheath for development of a basic understanding of ultrasound studies aimed to measure optic nerve sheath diameter (ONSD) for detection of acutely elevated intracranial pressure (ICP).
Annals of Surgery | 2005
Dieter C. Broering; Christian Wilms; C Lenk; Jan Schulte am Esch; Silke Schönherr; Lars Mueller; Jong-Sun Kim; Knut Helmke; Martin Burdelski; Xavier Rogiers
Objective:Splitting of the liver at the line of Cantlie of otherwise healthy people is accepted worldwide as a reasonable procedure for the donors in adult living donor liver transplantation. A similar operation is still considered as experimental if performed in the deceased donor liver. The aim of this study is to evaluate the technical evolution and the results of this variant splitting technique. Patients and Methods:From January 1999 to August 2004, a total of 35 transplants of hemilivers from deceased donors (segments V–VIII: n = 16 and segments (I)II–IV: n = 19) were performed in our center. Seven splits were performed in situ and 12 ex situ. Splitting of the vena cava was applied in 18 splits and splitting of the middle hepatic vein in 8. Seven adults and 12 adolescents received the left hemiliver with a mean age of 12 years (range, 3–64 years), of whom 21% were UNOS status 1. Recipients of right hemilivers were exclusively adults with a mean age of 48 years (range, 31–65 years), none of them were high urgent. The outcome of these 35 recipients of hemilivers was prospectively evaluated. Results:Mean deceased donor age was 27 years (range, 12–57 years), the donors body weight ranged between 55 kg and 100 kg. The mean weight of the right and left hemilivers was 1135 g (range, 745–1432 g) and 602 g (range, 289–1100 g), respectively. The mean graft recipient weight ratio in left and right hemiliver group was 1.46% (range, 0.88%–3.54%) and 1.58% (range, 1.15%–1.99%), respectively. Median follow-up was 27.4 months (range, 1–68.3 months). Four patients died (actual patient survival FR group: 87.5% versus FL group: 89.5%), 3 due to septic MOF and 1 due to graft versus host disease. In each of the 2 groups, 2 recipients had to undergo retransplantation, which resulted in an actual right and left hemiliver survival rate of 75% and 84%, respectively. The causes for retransplantation were primary nonfunction in 2 left hemilivers, chronic graft dysfunction in 1 right hemiliver, and recurrence of the primary disease in 1 recipient of a right hemiliver. Primary poor function was observed in 1 recipient of a right hemiliver. Early and late biliary complications occurred in both right and left hemiliver groups at the rate of 37.5% (n = 6) and 21% (n = 4), respectively. Arterial, portal, and venous complications were not observed in either group. Conclusion:The technical development of splitting along Cantlies line is almost complete with the last challenge being the reduction of biliary complications. The key to success is the choice of adequate deceased donors and recipients. Full-right full-left splitting is safely possible and should be considered as a reasonable instrument to alleviate mortality on the adult waiting list and to reduce the need for adult and adolescent living donation.
Transplantation | 2000
Knut Helmke; Martin Burdelski; Hans-Christian Hansen
BACKGROUND Development of elevated intracranial pressure (ICP) in hepatic failure indicates poor prognosis. Its detection by invasive methods poses methodological problems. We applied ultrasound studies of the optic nerves to noninvasively estimated ICP status. METHODS A total of 22 pediatric patients with hepatic failure were examined by serial B scan ultrasound and followed up clinically. Outcome was scored as survival or death due to multiorgan failure (MOF) or raised ICP. In 18 patients, transplantations were performed. RESULTS Four patients died before transplantation was possible (raised ICP: n=3, MOF: n=1). After OLT there were 10 survivors and 8 patients died (MOF: n=3, raised ICP: n=5). In 10 patients we found optic nerve sheath diameter (ONSD) above normal limits. Eight patients died, mostly because of raised ICP (n=7). Only 2 of the 10 survivors experienced a transient ONSD increase, steadily normalized after transplantation. Preoperatively, normal ONSD was detected in four of seven patients. The outcome of these four cases was clearly superior (three survivors and one MOF) compared with abnormal pre-OLT ultrasound findings (raised ICP: n=3). CONCLUSION Patients with poor prognosis related to raised ICP in pediatric liver failure can be identified by ultrasound measurement of ONSD without the disadvantages of invasive procedures. Although the exact intracranial pressure level cannot be deduced from single examinations, ONSD trends can reflect the evolution of ICP in hepatic encephalopathy.
Pediatric Transplantation | 2000
Rainer Ganschow; D. Nolkemper; Knut Helmke; E. Harps; J. C. Commentz; Dc Broering; W. Pothmann; Xavier Rogiers; H. H. Hellwege; M Burdelski
Abstract: A retrospective study was conducted to determine the significance of intensive care management on outcome after liver transplantation (LTx) in children. Of 195 transplants performed in 162 children, factors affecting morbidity and mortality were documented during the post‐operative intensive care unit (ICU) stay. To assess the gain in experience of ICU management, we compared mean ventilation time and stay in the ICU as well as mortality, incidence of surgical complications, infections, and rejection episodes, during three different time‐periods (October 1991–August 1994, September 1994–July 1996, and August 1996–February 1998). The time spent by patients in the ICU (9.7 days vs. 7.9 days vs. 4.7 days, p < 0.001) and time on ventilation (5.2 days vs. 3.1 days vs. 1.2 days, p < 0.001) were significantly reduced over the duration of the study. The overall mortality was 18.0% (n = 30) and 76.7% (n = 23) of these deaths occured during the early post‐operative period in the ICU. The incidence of severe surgical complications decreased significantly over time, and the application of intra‐operative Doppler ultrasound since 1994 led to detection of 27 correctable vascular complications. The overall incidence of acute cellular rejection episodes in our center was 64.1%: 43.5% of the infectious episodes occured in the ICU (bacterial 70.2%, viral 12.3%, and fungal 17.5%). The main side‐effect from immunosuppressive drugs was arterial hypertension in 29% of the patients. We conclude that our efforts to improve intensive care management and monitoring were the key elements in reducing morbidity and mortality after pediatric LTx.
Transplantation | 2005
Jong-Sun Kim; Rainer Grotelüschen; T Mueller; Rainer Ganschow; Turan Bicak; Christian Wilms; Lars Mueller; Knut Helmke; Martin Burdelski; Xavier Rogiers; Dieter C. Broering
Background. Since starting our program in 1989, 455 pediatric orthotopic liver transplantations have been performed using all techniques. In April 2001, we experienced our last in-hospital death of a pediatric liver-transplant recipient. Since then, all our liver-transplant children (n=170) were able to be discharged from the hospital. The aim of this study is to analyze the actual status of pediatric liver transplantation at the University of Hamburg and to find future perspectives to improve the results after pediatric liver transplantation. Methods. From May 4, 2001 until September 8, 2004, 22 (13%) whole organs, 18 (11%) reduced-size organs, 79 (47%) split organs, and 51 (30%) organs from living donors were transplanted into 142 patients. One hundred forty-one were primary liver transplants, 25 retransplants, 3 third, and 1 fourth liver transplants. Of the 170 orthotopic liver transplantations (OLT), 31 (18%) were highly urgent (United Network of Organ Sharing [UNOS] I). Results. After 170 consecutive pediatric liver transplants, no patients died during the hospital course (100% patient survival<3 months), but overall, 5 (2.9%) recipients died during further follow-up. The 3-month and actual graft survival rates are 93% and 85%, respectively. Twenty (11.8%) children had to undergo retransplantation. However, patient survival was not sustained by longer graft survival. Analyzing our series, we see that graft survival after reduced-size liver transplantation showed a significantly lower rate versus living-donor liver transplantation. Conclusion. The learning curve in pediatric liver transplantation has reached a turning point where immediate patient survival is considered the rule. The challenge is to increase graft survival to the same level. The long-term management of the transplant patients, with the aim of avoiding late graft loss and achieving excellent quality of life, will become the center of the debate.
Transplantation | 2009
Florian Brinkert; Rainer Ganschow; Knut Helmke; Egmond Harps; Lutz Fischer; Björn Nashan; Bernd Hoppe; Stephanie Kulke; Dirk E. Müller-Wiefel; Markus J. Kemper
Background. Cure of the metabolic defect in primary hyperoxaluria type 1 (PH1) is possible with liver transplantation (LTx). Preemptive LTx (PLTx) was promoted to prevent chronic kidney disease due to nephrocalcinosis and urolithiasis. However, timing of this procedure is difficult in view of the heterogeneity of PH1 and effective conservative treatment. Combined liver-kidney transplantation (LKTx) is able to cure metabolic defect and replace renal function at the same time and is effective and indicated for patients with or approaching end-stage renal disease (ESRD). Sometimes a sequential approach for LKTx (first liver, then kidney) has been recommended. Methods. We report on 13 patients with PH1 since 1995 who underwent transplantation procedures in our center for PH1 at a median age of 4.7 (range 1.4–8.9) years. Results. The first two patients, planned for a sequential strategy, died early after LTx because of infectious complications. Four patients underwent PLTx at a median glomerular filtration rate of 65 (range 27–98) mL/min/1.73 m2/day (Hoppe et al., Pediatr Nephrol 1996; 10: 488), and three patients still have sufficient residual renal function after a follow-up of median 11.6 years. Seven patients with ESRD received a combined LKTx, including four with infantile oxalosis, and three weighing less than 10 kg. There was no mortality and catch-up growth was observed in most patients. Conclusion. In summary and conclusion, transplantation procedures are challenging in PH1, but our results including growth data are encouraging. PLTx remains an option despite the difficulties in timing the procedure. LKTx is indicated for patients with ESRD and is possible even in patients with infantile oxalosis and may improve longitudinal growth.
Clinical Transplantation | 2007
Andrea Richter; Enke Grabhorn; Knut Helmke; Michael P. Manns; Rainer Ganschow; M Burdelski
Abstract: Background: The presence of autoantibodies and development of autoimmune hepatitis after liver transplantation has recently been reported as one of the causes for chronic graft dysfunction. The pathogenesis and clinical significance of this disease still remains unclear.