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31.
OBJECTIVES: To describe the results and complications of in situ preservation (ISP) of kidneys from donors after cardiac death (DCD). BACKGROUND: DCD donors are increasingly being used to expand the pool of donor kidneys. ISP reduces warm ischemic injury which is associated with DCD donation. METHODS: Insertion of a double-balloon triple-lumen catheter allows selective perfusion of the abdominal aorta to preserve the kidneys in situ. From January 2001 until August 2005, 133 ISP procedures were initiated in our procurement area. RESULTS: Fifty-six (42%) ISP procedures led to transplantation; in the remaining 77 cases (58%), the donation procedure was abandoned or both kidneys were discarded because of ISP complications (n = 31), poor graft quality (n = 23), no consent for donation (n = 13), medical contraindications (n = 8), or unknown cause (n = 2). Increasing donor age (odds ratio (OR) 1.06 per year, P < 0.001) and uncontrolled DCD donation (OR 5.4, P < 0.001) were independently correlated with ISP complications. After transplantation, prolonged double-balloon triple-lumen catheter insertion time was an independent predictor of graft failure (OR 2.0, P = 0.05). Selected controlled DCD donors were managed by rapid laparotomy and direct aortic cannulation; graft survival of these kidneys was superior to kidneys from controlled DCD donors managed by ISP. CONCLUSIONS: A minority of initiated ISP procedures led to transplantation, resulting in a high workload compared with donation after brain death. The association between increasing catheter insertion time and inferior graft outcome emphasizes the need for fast and effective surgery. Therefore, rapid laparotomy with direct aortic cannulation is preferred over ISP in controlled DCD donation. Despite these limitations, we have expanded our donor pool 3- to 4-fold by procuring DCD kidneys that were preserved in situ.  相似文献   
32.
Objective: The use of non-heart-beating donors (NHBD) has been propagated as an alternative to overcome the scarcity of pulmonary grafts. Formation of microthrombi after circulatory arrest, however, is a major concern for the development of reperfusion injury. We looked at the effect and the best route of pulmonary flush following topical cooling in NHBD. Methods: Non-heparinized pigs were sacrificed by ventricular fibrillation and divided into three groups (n = 6 per group). After 1 h of in situ warm ischaemia and 2.5 h of topical cooling, lungs in group I were retrieved unflushed (NF). In group II, lungs were explanted following an anterograde flush (AF) through the pulmonary artery with 50 ml/kg Perfadex® (6 °C). Finally, in group III, lungs were retrieved after an identical but retrograde flush (RF) via the left atrium. Flush effluent was sampled at intervals to measure haemoglobin concentration. Performance of the left lung was assessed during 60 min in our ex vivo reperfusion model. Wet-to-dry weight ratio (W/D) of both lungs was calculated as an index of pulmonary oedema. IL-1ß and TNF- protein levels in bronchial lavage fluid from both lungs were compared between groups. Results: Haemoglobin concentration (g/dl) was higher in the first effluent in RF versus AF (3.4 ± 1.1 vs 0.6 ± 0.1; p < 0.05). Pulmonary vascular resistance (dynes × s × cm−5) was 975 ± 85 RF versus 1567 ± 98 AF and 1576 ± 88 NF at 60 min of reperfusion (p < 0.001). Oxygenation (mmHg) and compliance (ml/cmH2O) were higher (491 ± 44 vs 472 ± 61 and 430 ± 33 NS, 22 ± 3 vs 19 ± 3 and 14 ± 1 NS, respectively) and plateau airway pressure (cmH2O) was lower (11 ± 1 vs 13 ± 1 and 13 ± 1 NS) after RF versus AF and NF, respectively. No differences in cytokine levels or in W/D ratios were observed between groups after reperfusion. Histology demonstrated microthrombi more often present after AF and NF compared to RF. Conclusion: Retrograde flush of the lung following topical cooling in the NHBD results in a better washout of residual blood and microthrombi and subsequent reduced pulmonary vascular resistance upon reperfusion.  相似文献   
33.
BACKGROUND: Optimal management in patients with umbilical hernias and liver cirrhosis with ascites is still under debate. The objective of this study was to compare the outcome in our series of operative versus conservative treatment of these patients. METHODS: In the period between 1990 and 2004, 34 patients with an umbilical hernia combined with liver cirrhosis and ascites were identified from our hospital database. In 17 patients, treatment consisted of elective hernia repair, and 13 were managed conservatively. Four patients underwent hernia repair during liver transplantation. RESULTS: Elective hernia repair was successful without complications and recurrence in 12 out of 17 patients. Complications occurred in 3 of these 17 patients, consisting of wound-related problems and recurrence in 4 out 17. Success rate of the initial conservative management was only 23%; hospital admittance for incarcerations occurred in 10 of 13 patients, of which 6 required hernia repair in an emergency setting. Two patients of the initially conservative managed group died from complications of the umbilical hernia. In the 4 patients that underwent hernia correction during liver transplantation, no complications occurred and 1 patient had a recurrence. CONCLUSIONS: Conservative management of umbilical hernias in patients with liver cirrhosis and ascites leads to a high rate of incarcerations with subsequent hernia repair in an emergency setting, whereas elective repair can be performed with less morbidity and is therefore advocated.  相似文献   
34.
Background:  Fatigue after liver transplantation (LTx) is a major problem that is associated with lower daily functioning and health-related quality of life (HRQoL). This study aimed to assess changes over time in fatigue following LTx. We also examined daily functioning and HRQoL changes over time and assessed the influence of fatigue and changes in fatigue on daily functioning and HRQoL. We determined whether sleep quality, anxiety, and depression were associated with fatigue.
Methods:  We identified 70 LTx recipients who had previously participated in a cross-sectional study and reassessed them after two yr to determine changes in level of fatigue, daily functioning, and HRQoL. We also assessed sleep quality, anxiety, and depression after two yr.
Results:  Level of fatigue and level of daily functioning were unchanged at follow-up. HRQoL domains remained stable or worsened. Fatigue was a significant predictor of daily functioning and all HRQoL domains (p < 0.01). Change in fatigue was a significant predictor of daily functioning and the HRQoL domains of "physical functioning,""vitality," and "pain" (p < 0.05). Sleep quality, anxiety, and depression were associated with fatigue severity (r = 0.35 to r = 0.60, p < 0.05).
Conclusion:  This longitudinal study shows that fatigue is a chronic problem after LTx and that daily functioning and HRQoL do not improve over time. This study supports the need for intervention programs to address fatigue after LTx.  相似文献   
35.

Background

The independent prognostic value of tumour volume in radical prostatectomy (RP) specimens is controversial, and it remains a matter of debate whether pathologists should report a measure of tumour volume. In addition, tumour volume might be of value in substaging of pathologic tumour stage (pT2) prostate cancer (PCa).

Objective

To assess the prognostic value of PCa tumour volume.

Design, setting, and participants

The cohort consisted of 344 participants in the European Randomised Study of Screening for Prostate Cancer (ERSPC), Rotterdam section, whose PCa was treated with RP. Mean time of follow-up was 96.2 mo.

Measurements

Tumour volume was measured in totally embedded RP specimens with a morphometric, computer-assisted method and assessed as a continuous variable, as relative tumour volume (tumour volume divided by prostate volume), and in a binary fashion (≥0.5 ml or <0.5 ml). These variables were related to prostate-specific antigen (PSA) progression, local recurrence, or distant metastasis and PCa-related mortality using univariate and multivariable Cox proportional hazards analyses. The analyses were repeated in the subgroup with pT2 tumours.

Results and limitations

Tumour volume was related to tumour stage, Gleason score, seminal vesicle invasion (SVI), and surgical margin status. In univariate analyses, tumour volume and relative tumour volume were predictive for all outcome variables. In multivariable analyses, including age, tumour stage, Gleason score, SVI, and surgical margin status, neither tumour volume nor relative volume were independent predictors of progression or mortality. Tumour volume ≥0.5 ml was predictive for PSA recurrence and local and/or distant progression in univariate analyses but not in multivariable analyses. Tumour volume was not predictive for recurrence or mortality in univariate or multivariable analyses in the pT2 subgroup.

Conclusions

Tumour volume did not add prognostic value to routinely assessed pathologic parameters. Therefore, there seems to be little reason to routinely measure tumour volume in RP specimens.  相似文献   
36.
Intraductal papillary-mucinous neoplasm (IPMN) of the pancreas is a clinically and morphologically distinctive precursor lesion of pancreatic cancer, characterized by gradual progression through a sequence of neoplastic changes. Based on the nature of the constituting neoplastic epithelium, degree of dysplasia and location within the pancreatic duct system, IPMNs are divided in several types which differ in their biological properties and clinical outcome. Molecular analysis and recent animal studies suggest that IPMNs develop in the context of a field-defect and reveal their possible relationship with other neoplastic precursor lesions of pancreatic cancer.  相似文献   
37.
BACKGROUND: In an attempt to reduce late referral and to improve the care of patients with chronic kidney disease (CKD), different organizations have issued guidelines on when to refer patients to the nephrologist. Most suggest referral of patients with a GFR below 60 ml/min/1.73 m2, and demand referral if the GFR is below 30 ml/min/1.73 m2. It is recommended to use the abbreviated MDRD equation to estimate GFR. This formula is, however, sensitive to the creatinine assay methodology. In addition, the impact of the implementation of such guidelines on the nephrology practice has never been evaluated. This study (i) identifies the true burden of CKD in a population and simulates the effects of a 100% implementation of the guidelines on the nephrology work load, and (ii) evaluates the validity of the estimated GFR using the abbreviated MDRD formula when routinely provided. METHODS: Different laboratories (both hospital and private) in our region were asked to report on all the serum creatinine values performed during the first week of December 2004. If patients had more than one determination, only the lowest serum creatinine value was retained. Patients already known to a nephrology unit were not included. GFR was calculated using the abbreviated MDRD, using the serum creatinine as reported by these laboratories, or after correction to the MDRD-standard using different published equations. RESULTS: 20,108 patients, with a mean age of 53.4+/-16.2 years, 48% females, had at least one serum creatinine determination in the observation period. According to the K/DOQI CKD classification, 20.2, 1.6 and 0.8% of females and 13.3, 1.6 and 0.6% of males were in stage 3, 4 and 5, respectively, when the abbreviated MDRD formula was used with the serum creatinine value as reported by the laboratories. Important differences in classifications were obtained when the different correction formulae for creatinine were applied. According to the current recommendations, this would lead to a mandatory referral of 1650-2400 CKD stage 4 patients per 100 000 inhabitants and a suggested referral of another 4100-15 360 CKD stage 3 patients per 100,000 inhabitants to a nephrology unit. CONCLUSION: Implementation of the current guidelines for referral of CKD patients to nephrologists would lead to an overload of the nephrology care capacities. Large differences in estimated GFRs with different corrections for serum creatinine are observed, resulting in important CKD classification differences. Standardization of serum creatinine assays is mandatory before guidelines, and especially the routine provision of the estimated GFR by the abbreviated MDRD formula, can be implemented in clinical practice.  相似文献   
38.
BACKGROUND & AIMS: Collagenous colitis (CC) is a well-described entity causing chronic diarrhea and characteristic histologic findings. Several treatment options have been suggested, but no controlled data are available. We conducted a placebo-controlled trial to show the clinical and histologic effects of budesonide in CC. METHODS: Twenty-eight patients were randomly assigned to receive placebo (n = 14) or budesonide 9 mg daily (n = 14) for 8 weeks. Patients were evaluated clinically, and blinded biopsy specimens were analyzed from fixed locations at weeks 0 and 8. Clinical response was defined as a decrease of at least 50% in the disease activity score (number of bowel movements in the last 7 days). At week 8, nonresponders received open-label budesonide for the next 8-week period; responders discontinued treatment and were followed up. RESULTS: Three patients discontinued the study prematurely. Intention-to-treat analysis showed clinical response in 8 of 14 patients in the budesonide group compared with 3 of 14 responders for placebo (P = 0.05) after 8 weeks of blinded therapy, together with improved stool consistency. Histologically, there was no change in the mean thickness of the collagen band but a significant decrease of the lamina propria infiltrate in the budesonide group (P < 0.001). CONCLUSIONS: Budesonide is efficacious in inducing short-term clinical response in CC with significant reduction of the histologic infiltrate in the lamina propria.  相似文献   
39.
PURPOSE: To characterize the flow dynamics of albumin ultrasound contrast microspheres containing perfluoropropane (PFP) in normal and inflamed microvasculature. MATERIALS AND METHODS: Mesenteric microvessels of rats were examined after an intravenous injection of fluorocein-labeled erythrocytes or PFP microspheres by fluorescence intravital microscopy with and without local application of 10(-8) M platelet activating factor (PAF) as an experimental form of inflammation. RESULTS: All the microspheres passed freely through arterioles and capillaries. Mean velocities of the microspheres in each vessel were closely correlated with those of erythrocytes. Only a minor fraction of the microspheres was retained in the venules (> or =0.1 s stoppage) by attachment to endothelial cells. The frequency of microsphere retention in venules was significantly enhanced by PAF (2.6+/-2.1%, P<0.01 vs. control), especially in regions with leukocyte adhesion. Treatment with a monoclonal antibody to intercellular adhesion molecule-1, P-selectin or the common leukocyte antigen inhibited PAF-induced microsphere retention in venules (P<0.05). In the inflamed microcirculation, a small subgroup of microspheres becomes attached to venular endothelial cells in regions with leukocyte adhesion via interaction among microspheres, activated leukocytes and endothelial cells via adhesion molecules. CONCLUSION: In inflamed microcirculation, a small subgroup of microspheres becomes attached to venular endothelial cells in regions with leukocyte adhesion via interaction among microspheres, activated leukocytes and endothelial cells via adhesion molecules. These results suggest that ultrasonography with microspheres has the potential to evaluate inflammatory site distribution as well as tissue perfusion.  相似文献   
40.
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