B Stange

Postoperative tracheal extubation after orthotopic liver transplantation

Background: The duration of postoperative mechanical ventilation and its influence on pulmonary function in liver transplant recipients is still debated controversially.

Clinical Implications of Hepatic Preservation Injury After Adult Liver Transplantation

Several advances in organ preservation have allowed for improved results after liver transplantation; however, little information is available regarding the clinical impact of preservation injury on the postoperative course. The medical records of 889 liver transplants were retrospectively reviewed. Preservation injury was classified according to postoperative aspartate aminotransferase values as minor (<1000 U/L), moderate (1000–5000 U/L), or severe (>5000 U/L). The following criteria were analyzed and compared according to the extent of preservation injury: patient and graft survival, retransplantation rate, duration of hospitalization and postoperative ventilation, as well as incidence of rejection, infection, and hemodialysis. The majority of patients received a liver with minor preservation injury (75.9%), whereas 22.7% and 1.3% of grafts showed moderate or severe injury. Graft survival was significantly lower in patients with severe preservation injury, when compared to minor or moderate injury. The relative risk for initial nonfunction was 39.36‐fold increased (95% confidence interval (ci): 10.3–150.2), as it was increased for duration of postoperative ventilation (6.92‐fold; 95%ci: 2.1–22.3) and hemodialysis (6.13‐fold; 95%ci: 1.9–19.3). Since the incidence of retransplantation was significantly increased (50%), patient survival remained comparable between all groups. Severe preservation injury had a tremendous impact on the postoperative clinical course, requiring the maximum medical effort to achieve adequate patient survival.

Incidence and indications for reintubation during postoperative care following orthotopic liver transplantation

STUDY OBJECTIVE To analyze the incidence and indications for reintubation during postoperative care following orthotopic liver transplantation (OLT). DESIGN Retrospective chart review. SETTING Large metropolitan teaching hospital. PATIENTS 546 adult liver transplant recipients. MEASUREMENTS AND MAIN RESULTS The medical charts of 546 patients who underwent OLT at our institution between January 1992 and September 1996 were reviewed for the incidence and indications of reintubation throughout primary hospitalization. Eighty-one of 546 patients (14.8%) required one or more episodes of reintubation after OLT. In the majority of cases, reintubation was performed for pulmonary complications (44.6%), followed by cerebral (19.1%) and surgical (14.5%) complications. Cardiac (9.1%) and peripheral neurologic (2.7%) complications were less frequent reasons for reintubation. Overall patient survival, according to the Kaplan-Meier estimates, was 89.9%, 87.5%, 86.5%, and 82.2% after 1, 2, 3, and 5 years, respectively. In patients with one or more episodes of reintubation, overall survival decreased to 62.5% after 1, 2, and 3 years, and to 56.4% after 5 years (p < 0.001). CONCLUSIONS The main indications for reintubation after OLT were pulmonary, cerebral, and surgical complications. These reintubation events had a considerable influence on the patients postoperative recovery, and were associated with a significantly higher rate of mortality, than for OLT patients who did not undo reintubation.

Hepatic Resection in Liver Transplant Recipients: Single Center Experience and Review of the Literature

Biliary complications such as ischemic (type) biliary lesions frequently develop following liver transplantation, requiring costly medical and endoscopic treatment. If conservative approaches fail, re‐transplantation is most often an inevitable sequel. Because of an increasing donor organ shortage and unfavorable outcomes in hepatic re‐transplantation, efforts to prolong graft survival become of particular interest. From a series of 1685 liver transplants, we herein report on three patients who underwent partial hepatic graft resection for (ischemic type) biliary lesions. In all cases, left hepatectomy (Couinauds segments II, III and IV) was performed without Pringle maneuver or mobilization of the right liver. All patients fully recovered postoperatively, but biliary leakage required surgical revision twice in one patient. At last follow‐up, two patients presented alive and well. The other patient with persistent hepatic artery thrombosis (HAT), however, demonstrated progression of disease in the right liver remnant and required re‐transplantation 13 months after hepatic graft resection. Including our own patients, review of the literature identified 24 adult patients who underwent hepatic graft resection. In conclusion, partial graft hepatectomy can be considered a safe and beneficial procedure in selected liver transplant recipients with anatomical limited biliary injury, thereby, preserving scarce donor organs.

Enhanced cytolytic activity of intestinal intraepithelial lymphocytes in patients with Crohn's disease.

Abstract  Background and aims: Dysfunction of the immune system with inappropriate responses of lymphocytes to various antigens has been implicated in the development of Crohn’s disease. Therefore, the functional and phenotypic characteristics of intestinal intraepithelial lymphocytes (IEL) in comparison to peripheral blood lymphocytes (PBL) were analyzed in patients with and without Crohn’s disease. Patients and methods: Six patients with Crohn’s disease and six control patients were studied. Isolated IEL and PBL were tested for cytolytic activity against the human adenocarcinoma cells DLD-1 and the human leukemia cells K562 in a 51Cr-release assay. Two-color flow cytometry was performed for phenotype analysis of isolated lymphocytes. Results: IEL from patients with Crohn’s disease showed significantly increased cytolytic activity against epithelial-derived target cells when compared with IEL from control patients. In contrast, no functional changes were detectable among PBL from patients with Crohn’s disease. IEL from patients with Crohn’s disease contained a significantly higher percentage of CD8+ lymphocytes when compared with IEL from control patients, whereas no phenotypic changes were observed among PBL. Conclusions: In Crohn’s disease, the functional and phenotypic changes of T cells are limited to lymphocytes of the intestinal mucosa. Furthermore, it is conceivable that the increased cytolytic activity of IEL contributes to the tissue damage in this disease.

Upregulation of intraepithelial lymphocyte (IEL) function in the small intestinal mucosa in sepsis.

Host defense mechanisms preventing bacterial invasion are particularly important in the gastrointestinal tract, since most gram-negative infections originate from there. Intraepithelial lymphocytes (IEL) seem to play an important role in this immune surveillance of the intestine, although their function in sepsis is not fully understood. To evaluate the characteristics of IEL in sepsis, C57BL/6 mice received a non-lethal dose of LPS and IEL were harvested at various time points thereafter. Although IEL displayed no phenotypic changes after endotoxemia, they displayed enhanced cytolytic activity and increased proliferation after LPS injection In addition, IEL from septic mice showed enhanced gamma interferon (IFN-gamma) production after LPS administration. The production of IFN-gamma may have induced the increased intestinal NOS-2 mRNA expression which was observed after endotoxemia. In conclusion, endotoxemia leads to functional activation of IEL without phenotypic changes. The activation of IEL and the subsequently increased NOS-2 expression may be important mechanisms in maintaining the mucosal barrier after sublethal LPS challenge.

Failure of Immediate Tracheal Extubation After Liver Transplantation - A Single Center Experience

Fast tracking approaches in liver transplantation include postoperative extubation immediately after surgery in the operating theatre. Based on the experience of 837 liver transplantations performed between 01/97 and 05/05, we report on the safety and feasibility of this procedure in almost 80% of transplant recipients, without increasing the incidence of subsequent reintubation (11%). This patient population experienced significantly higher survival compared to patients in whom extubation succeeded at the intensive care unit (p<0.02). Special attention was required for recipients with acute liver failure or retransplantation. These patients did not participate in fast tracking protocols, as demonstrated by a multi- variate regression analysis. In this context, failure of immediate tracheal extubation was independent of cold ischemic time, duration of surgery, donor / recipient age or gender, extent of preservation injury, or type of organ donation (post- mortal vs living-related). ROC analysis revealed that only intraoperative transfusions of � 6 units of red blood cells were associated with primary extubation in the operating theatre with high sensitivity and specifity. To conclude, postoperative mechanical ventilation is justified only in a small cohort of recipients. For the vast majority ofpatients, immediate post- operative tracheal extubation should be the standard procedure after liver transplantation.

Interleukin-2 mindert den oxidativen Stress und stabilisiert das Verhältnis der Subpopulationen intraepithelialer Lymphozyten nach Ischämie/Reperfusion des Dünndarms

Hintergrund: Oxidativer Stres mit massiver Zellschadigung und konsekutiver Beeintrachtigung der mukosalen Barrierefunktion liegt dem Ischamie/Reperfusionsschaden (I/R) im Dunndarm zu Grunde. Wenig bekannt sind dabei die Veranderungen intraepithelialer Lymphozyten (IEL), einer zum Barrieresystem beitragenden Zellpopulation. In der vorliegenden Studie wurden daher bei I/R und nach Modulation des I/R durch In-terleukin-2 (IL-2), Phanotyp und Proliferation intestinaler IEL, sowie die Expression der induzierbaren Nitric-Oxide Synthase (iNOS) im Darm untersucht.

Erhöhte Anzahl und Aktivität von NK-Zellen im peripheren Blut bei Patienten mit nichtmetastasiertem Kolonkarzinom

Naturliche Killerzellen (NK-Zellen) unterscheiden sich von T- und B-Lymphozyten durch ihre Fahigkeit eine Vielzahl von Zielzellen spontan und nicht-MHC restringiert zu lysieren [1]. Insbesondere bei der Tumorabwehr spielt dieser Mechanismus eine wichtige Rolle. In verschiedenen Studien wurde ein Zusammenhang zwischen verringerter NK-Zell-Anzahl bzw. verringerter NK-Aktivitat und der Tumorausbreitung gezeigt [2, 3]. Bei verschiedene Tumorerkrankungen (Bronchial-Ca, Mamma-Ca, Ovarial-Ca, Prostata-Ca, Blasen-Ca, Hepatocellulares-Ca u.a.) gilt eine verringerte NK-ZeII-Aktivitat als negativ prognostischer Marker [4,5]. Ahnliche Untersuchungen bei Patienten mit Kolonkarzinom sind dagegen in ihren Aussagen widerspruchlich [6, 7]. In der vorliegenden Studie wurde daher die NK-ZeII-Anzahl und NK-Aktivitat bei Patienten mit Kolonkarzinomen in verschiedenen Stadien (nichtmetastasiert/metastasiert) im Vergleich zu Kontrollpatienten untersucht.