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OBJECTIVE: Organ transplantation is limited by the number of brain-dead human donors. Xenotransplantation could be an alternative to guarantee a constant supply of organs. A major problem of xenotransplantation are xenogeneic natural antibodies (XNAb) directed against species-specific antigens of a discordant donor species (e.g. pig). They trigger the hyperacute xenograft rejection (HXR). Re-usable immunoapheresis (LA)-columns Ig-Therasorb (Therasorb, Baxter) were used to adsorb these XNAb. The effect of immunoapheresis of the perfusing human blood was investigated in ex vivo working pig hearts. METHODS: Hearts of 12 landrace pigs (body weight 14-31 kg) were explanted after inducing cardiac arrest with 4 degrees C Celsior solution. Human blood (500 ml, heparinized) was obtained from healthy volunteers. In group 1 (G1, n = 6), blood as perfusate remained untreated. In group 2 (G2, n = 6), native blood was separated by plasmapheresis into cellular components and plasma. The latter passed through the Ig-Therasorb column for removal of immunoglobulins (so-called immunoadsorption or immunoapheresis). After back-table preparation the hearts were mounted to the working heart model. After 20 min of reperfusion in Langendorff mode, the working heart mode was established. Blood samples were taken isochronously for measurement of: CK(-MB), LDH, ASAT, troponin, immunoglobulins, complement activity, anti-pig antibodies and others. After cessation of the heart, atrial and ventricular tissue samples were taken for histological examinations (light/electron microscopy and immunohistochemistry). RESULTS: Two cycles of immunoapheresis reduced the levels of IgG by 84%, IgM by 83.3% and IgA by 76%. In G2, the antibody immunoadsorption of blood prolonged the duration of the working heart mode significantly to 335+/-37.5 min. In contrast, hearts of group 1 (control) failed after 125+/-31.3 min. Heart rate was significantly different between both groups (G1, 77.3+/-6.1 beats/min; G2, 86.5+/-5.5 beats/min). In G2 cardiac output was 118% and mean coronary flow was 154.6% higher than in G1. CK, LDH and ASAT showed no differences in the two groups. Heart weight increased significantly more in group 1 than in G2. Histological examination indicated specific signs of HXR in G1 after 1.5 h, whereas in G2 only slight unspecific damages were found after 6 h. CONCLUSION: Antibody removal by means of immunoapheresis results in a significantly improved xenogeneic cardiac function. Immunoapheresis may, therefore, become an important adjunct in future pig-to-man clinical xenotransplantation.  相似文献   
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The aim of our study was to evaluate the impact of intraoperative parathyroid hormone (PTH) measurement on surgical results in patients with renal hyperparathyroidism (HPT). From December 1999 to February 2004, a series of 95 consecutive patients underwent total parathyroidectomy and intraoperative PTH measurement for renal HPT. Intraoperative PTH was measured before and 15 minutes after parathyroidectomy with the Immulite DPC assay for intact PTH. The median PTH levels before surgery were 133.0 pmol/L, which declined to 5.9 pmol/L at the end of the operation. At follow-up, 91 of 95 (96%) patients presented with normal calcium levels. Persistent renal HPT was seen in three patients, and recurrent HPT was diagnosed in another. In 99% of the patients the intraoperative PTH levels declined more than 50% and in 73% the PTH decay was more than 90%. In 64% of the patients PTH levels dropped into the normal range (< 7.6 pmol/L). Altogether, 97% of the patients with an intraoperative PTH decrease of more than 90% presented with normal PTH levels postoperatively (p = 0.0237), as did all of the patients whose intraoperative PTH dropped into the normal range (p = 0.0432). Intraoperative PTH measurement with a decrease in intraoperative PTH of at least 90% is highly predictive of successful parathyroidectomy and normalization of postoperative calcium and PTH levels.  相似文献   
15.
Mythos OP-Minute     
The economic situation in German Hospitals is tense and needs the implementation of differentiated controlling instruments. Accordingly, parameters of revenue development of different organizational units within a hospital are needed. This is particularly necessary in the revenue and cost-intensive operating theater field. So far there are only barely established productivity data for the control of operating room (OR) revenues during the year available. This article describes a valid method for the calculation of case-related revenues per OR minute conform to the diagnosis-related groups (DRG).  相似文献   
16.
High degrees of premature retirement among teachers warrant investigating the occupational burden and the mental health status of this profession. A sample of 1074 German teachers participated in this study. Two samples of the general population (N = 824 and N = 792) were used as comparison groups. Work distress was assessed with the Effort–Reward‐Imbalance questionnaire, and mental health problems were measured with the General Health Questionnaire (GHQ‐12). Teachers reported more effort–reward imbalance (M = 0.64) compared with the general population (M = 0.57), and they perceived more mental health problems (GHQ: M = 12.1) than the comparison group (M = 9.5). School type was not associated with work stress and mental health. Teachers with leading functions perceived high degrees of effort and reward, resulting in a moderate effort–reward ratio and no heightened mental health problems. Teachers working full time reported more effort than teachers working part time, but the reward mean values of both groups were similar. This results in a somewhat unfavourable effort–reward ratio of teachers working full time. Moreover, teachers working full time reported more mental health problems. The results support the appropriateness of the effort–reward conception, applied to the profession of teachers. The higher degree of effort–reward imbalance and the level of mental health problems warrant preventive measures. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
17.

Introduction

Pancreaticoduodenectomy (PD) is the standard operation for cancer of the pancreatic head. To achieve complete tumor resection and, thus, improve long-term survival, venous resection of the portal or superior mesenteric vein with reconstruction has become routine for advanced pancreatic adenocarcinoma (PDAC). However, its clinical benefit still remains controversial. The aim of this study was to investigate morbidity, mortality, and survival of patients with advanced PDAC following PD with venous resection and to identify significant survival determinants.

Material and Methods

From October 2001 to December 2007, 488 patients with PDAC of the pancreatic head underwent PD at our department. Venous resection was performed in 110 patients (22.5%). Clinical data, surgical techniques, perioperative parameters, and histopathologic data were analyzed on a prospective database.

Results

Major venous reconstruction was accomplished through primary lateral venorrhaphy in 18 patients (16.3%), polytetrafluoroethylene grafting (n?=?14, 12.7%), primary end-to-end anastomosis (n?=?72, 65.5%), an autologous saphenous venous graft patch (n?=?4, 4.6%) or a Goretex® patch (n?=?2, 2.3%). In 78.1% histopathologic examination revealed cancer invasion of the vein, whereas the remainder had peritumoral inflammation extending to the vessel wall. Perioperative morbidity rate was 41.8%; and the mortality rate 3.6%. The 1-, 2-, and 3-year survival rates were 55.2%, 23.1%, and 14.4%, respectively. Operating time (>420 min) and advanced age (>70 years) were the only prognostic variables, which significantly diminished survival on multivariate analysis.

Conclusion

Resection of the superior mesenteric or portal vein to achieve macroscopic tumor clearance can be performed safely with acceptable operative morbidity and mortality. However, improved local clearance in these patients cannot achieve a favorable long-term survival for all patients because distant metastases or local recurrence is frequent.  相似文献   
18.
Background The value of re-exploration for pancreatic ductal adenocarcinoma after the initial diagnosis of unresectability is unclear. Methods In this study, we analyzed 33 patients who were re-explored after an initial diagnosis of unresectability. Results At the time of reoperation, a resectable tumor was found in 18 patients: therefore, 15 pancreaticoduodenectomies, two total pancreatectomies and one left resection were performed with three vascular resections. Morbidity and mortality rates for the cohort were 6/33 and 1/33, without significant differences between resectable and nonresectable patients. Length of stay, duration of operation, and blood loss were significantly increased in the resection group. Kaplan–Meier survival analysis demonstrated increased median survival for resected patients (1078 days after the initial operation versus 547 days in the group of unresectable patients; p = 0.018). Analysis of the reasons against initial resection showed that, if the patients had been sent to a tertiary referral center for pancreatic surgery, a different decision in favor of resection would probably have been made in 14 out of 33 patients. A review of 10 published reports on reoperation for pancreatic cancer revealed results comparable to our study in terms of low morbidity and mortality as well as a survival benefit. Conclusions Reoperation for pancreatic ductal adenocarcinoma that is initially deemed unresectable can be safely performed in a selected group of patients by experienced surgeons, supporting the concept of patient centralization in pancreatic surgery. Resection at the second operation may confer a survival benefit even when the initial findings preclude a potentially curative approach.  相似文献   
19.
Is there still a role for total pancreatectomy?   总被引:3,自引:0,他引:3       下载免费PDF全文
OBJECTIVE: To evaluate the perioperative and long-term results of total pancreatectomy (TP), and to assess whether it provides morbidity, mortality, and quality of life (QoL) comparable to those of the pylorus-preserving (pp)-Whipple procedure in patients with benign and malignant pancreatic disease. SUMMARY BACKGROUND DATA: TP was abandoned for decades because of high peri- and postoperative morbidity and mortality. Because selected pancreatic diseases are best treated by TP, and pancreatic surgery and postoperative management of exocrine and endocrine insufficiency have significantly improved, the hesitance to perform a TP is disappearing. PATIENTS AND METHODS: In a prospective study conducted from October 2001 to November 2006, all patients undergoing a TP (n = 147; 100 primary elective TP [group A], 24 elective TP after previous pancreatic resection [group B], and 23 completion pancreatectomies for complications) were included, and perioperative and late follow-up data, including the QoL (EORTC QLQ-C30 questionnaire), were evaluated. A matched-pairs analysis with patients receiving a pp-Whipple operation was performed. RESULTS: Indications for an elective TP (group A + B) were pancreatic and periampullary adenocarcinoma (n = 71), other neoplastic pancreatic tumors (intraductal papillary mucinous neoplasms, neuroendocrine tumors, cystic tumors; n = 34), metastatic lesions (n = 8), and chronic pancreatitis (n = 11). There were 73 men and 51 women with a mean age of 60.9 +/- 11.3 years. Median intraoperative blood loss was 1000 mL and median operation time was 380 minutes. Postoperative surgical morbidity was 24%, medical morbidity was 15%, and mortality was 4.8%. The relaparotomy rate was 12%. Median postoperative hospital stay was 11 days. After a median follow-up of 23 months, global health status of TP patients was comparable to that of pp-Whipple patients, although a few single QoL items were reduced. All patients required insulin and exocrine pancreatic enzyme replacements. The mean HbA1c value was 7.3% +/- 0.9%. CONCLUSION: In this cohort study, mortality and morbidity rates after elective TP are not significantly different from the pp-Whipple. Because of improvements in postoperative management, QoL is acceptable, and is almost comparable to that of pp-Whipple patients. Therefore, TP should no longer be generally avoided, because it is a viable option in selected patients.  相似文献   
20.

Background  

Low cardiac output (LCO) after corrective surgery remains a serious complication in pediatric congenital heart diseases (CHD). In the case of refractory LCO, extra corporeal life support (ECLS) extra corporeal membrane oxygenation (ECMO) or ventricle assist devices (VAD) is the final therapeutic option. In the present study we have reviewed the outcomes of pediatric patients after corrective surgery necessitating ECLS and compared outcomes with pediatric patients necessitating ECLS because of dilatated cardiomyopathy (DCM).  相似文献   
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