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111.
BACKGROUND: Early implantation of centrifugal devices in patients with postcardiotomy cardiogenic shock may provide a bridge to recovery and allow subsequent long-term survival. METHODS: Since January 1989, 62 patients were supported with centrifugal pumps because of failure to wean from cardiopulmonary bypass. Indications were postcardiotomy cardiogenic shock (PCCS) (n = 60), bridge to cardiac retransplantation (n = 1), and right ventricular failure (n = 1). Patients' ages ranged from 23 to 78 years; 40 were men (65%), and 22 were women (35%). Twenty-two patients (35%) had a left ventricular assist device; 9 patients (15%) had a right ventricular assist device; and 31 patients (50%) had a biventricular assist device. Length of support ranged from 1 day to 19 days. RESULTS: Forty-two patients (68%) were weaned successfully; 27 patients survived to discharge (44%). Complications included bleeding (n = 41, 66%), renal failure (n = 28, 45%), and respiratory failure (n = 26, 42%). Currently, 23 patients survived 10 or more years (n = 1), 6 to 10 years (n = 7), 1 to 5 years (n = 10), and less than 1 year (n = 5). CONCLUSIONS: Centrifugal pumps are available, easy to use, and relatively inexpensive. Our experience justifies their continued use as a bridge to recovery for patients with postcardiotomy cardiogenic shock, despite the availability and increasing use of more expensive devices.  相似文献   
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BACKGROUND: Critical organ shortage in lung transplantation could be attenuated by the use of non-heart-beating donor (NHBD) lungs. In addition, prolonged ischemic tolerance of the organs would contribute to the alleviation of organ shortage. The aim of this study was to investigate pulmonary graft function of NHBD lungs after long-term hypothermic storage. METHODS: Twelve native-bred pigs (bodyweight 20 to 30 kg) underwent left lung allotransplantation. In the heart-beating donor (HBD) group, lungs were harvested immediately after cardiac arrest. In the NHBD group, lungs were subjected to a warm ischemic period of 90 minutes before harvesting. After a total ischemic time of 19 hours, pulmonary grafts in both groups were reperfused and pulmonary graft function was assessed. All values were compared with a sham-operated control group. RESULTS: Pulmonary graft function in the HBD group was excellent. In the NHBD group, pulmonary gas exchange was impaired, but still provided good graft function compared with the excellent graft function in the HBD group. Pulmonary vascular resistance was even lower in the NHBD group. In the NHBD group, calculated intrapulmonary shunt fraction (Qs/Qt) was significantly increased compared with the sham-group. Histologic alteration and wet-to-dry ratio did not differ significantly between the HBD and NHBD group. CONCLUSIONS: We conclude that NHBD lungs (90 minutes of warm ischemic time) have the potential to alleviate organ shortage in lung transplantation even after an extended total ischemic time.  相似文献   
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The international prognostic scoring system (IPSS) is considered the gold standard for risk assessment in primary myelodysplastic syndromes (MDS). This score includes several prognostic factors except serum lactate dehydrogenase (LDH). We evaluated the prognostic power of LDH as an additional variable in IPSS-based risk assessment. For this purpose, a total of 892 patients with primary MDS registered by the Austrian-German cooperative MDS study group was analyzed retrospectively. Multivariate analysis confirmed the value of established parameters such as medullary blasts, karyotype and peripheral cell counts and showed that elevated LDH was associated with decreased overall survival (P<0.00005) and increased risk of AML development (P<0.00005), independent of the system used to classify MDS (FAB or WHO). Moreover, elevated LDH was found to be a significant predictor of poor survival within each IPSS risk group and within each FAB group except RAEB-T. To exploit these results for refined prognostication, each IPSS risk group was split into two separate categories (A=normal LDH vs B=elevated LDH). Using this LDH-assisted approach, it was possible to identify MDS patients with unfavorable prognosis within the low and intermediate IPSS risk groups. We propose that the IPSS+LDH score should improve clinical decision-making and facilitate proper risk stratification in clinical trials.  相似文献   
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OBJECTIVES: We sought to analyze the experience with bronchoplastic procedures over a 7-year period and to determine putative prognostic factors for survival. METHODS: From 1991 to 1997, 144 bronchoplastic procedures were performed for non-small cell lung cancer (n = 123), small cell lung cancer (n = 5), carcinoid tumor (n = 10), and metastases of extrathoracic malignant tumors (n = 6). There were 111 sleeve lobectomies, 17 bilobectomies, 4 lobectomies with carinal resection, 8 sleeve pneumonectomies, and 4 bronchotomies without parenchymal resection. Multivariable analysis included risk factors, such as age, sex, type of bronchoplastic procedure (bronchotomy, lobectomy, bilobectomy, or pneumonectomy), additional angioplasty, TNM staging, histology, radicality of resection, respiratory risk (forced expiratory volume in 1 second, percent predicted < 60), cardiovascular risk, and adjuvant therapy. RESULTS: Overall 1- and 3-year survival was 72% and 52%, respectively. The overall 30-day mortality was 8.3% (5.4% for single sleeve lobectomies). Multivariable analysis demonstrated 4 risk factors for survival. High tumor stage, type of bronchoplastic procedure, impaired lung function, and presence of cardiovascular risk were associated with a poor outcome. Univariate analysis showed reduced survival in patients with sleeve pneumonectomies (1-year survival, 25%). CONCLUSIONS: Bronchoplastic procedures for central tumors and sleeve pneumonectomies are associated with poor survival. Careful selection of these patients, as well as of patients with impaired lung function and cardiovascular risk factors, is mandatory.  相似文献   
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Embryonic stem cell (ES) technology has advanced considerably within the past three decades and has gained prominent distinction within the emerging field of regenerative medicine. As it now enters the nascent stages of clinical application, many hopes and expectations arise along with questions as to where the technology will go. This paper evaluates the technical and practical obstacles that must be overcome before it can fully translate into the clinical context, the existence of strong opposition to the technology, political and legal barriers that have impeded its progression, and the role of healthcare reform in creating new social and economic priorities. In contrast to the technological imperative, a driving force seeking to implement the most recent scientific advances into medical practice, we refer to such translational obstacles as “technological impedance.” Rather than expending inordinate effort to preserve existing systems that continue to possess major hurdles, we advocate fostering interdisciplinary approaches in the development of new generation platforms and embracing disruptive innovations that create solutions to technological impedance and move us forward in healthcare delivery. Clin Trans Sci 2012; Volume 5: 422–427  相似文献   
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Background contextPedicle screws have shown to be a safe and effective method of spinal fixation, offering superior multiplanar correction compared with hooks or sublaminar wires in selected situations. Though only food and drug administration (FDA) approved in the adolescent population, they are commonly used in an off-label manner in the preadolescent population.PurposeTo determine if the complication rate of the off-label use of pedicle screws for spinal fixation in the preadolescent 0- to 12-year-old population is comparable with the complication rate in the FDA-approved 13- to 18-year-old population.Study design/settingRetrospective medical record and radiograph review.Patient sampleA total of 726 pediatric patients who underwent a spinal fusion procedure at a single tertiary institution between January 2003 and December 2008 were reviewed.Outcome measuresIncidence of instrumentation failure, infection, neurological complication, and total complications.MethodsThe study population was divided into two groups based on age: the younger group included 0- to 12-year olds and the older group included 13- to 18-year olds at the time of surgery. Groups were further subdivided based on diagnosis: “A,” neuromuscular scoliosis; “B,” idiopathic scoliosis, and “C,” other spinal deformities. Rates of neurovascular complications, infections, and instrumentation complications were compared statistically between the younger and the older groups. Only patients with greater than or equal to 1-year follow-up and greater than or equal to 2-year follow-up were included in the calculations for infection and instrumentation complication rates, respectively.ResultsThere were 206 patients (33% males, 67% females) in the younger group (0 to 12 years) and 520 (41% males, 59% females) in the older group (13 to 18 years). Overall, younger group had a 13.6% complication rate compared with 16.9% in the older group. Younger subjects showed a 13.4% complication rate because of instrumentation-related complications, 0.5% for neurovascular complications, and an infection rate of 9.2%. The older group showed a 15.4% complication rate because of instrumentation-related complications, 1.92% for neurovascular complications, and an infection rate of 11.0%. Complication rates were statistically insignificant between the two groups. Other complications in the younger group included one patient with aspiration pneumonia, two with ileus, and one with pulmonary and other complications in the older group included one patient with aspiration pneumonia, two with ileus, three with superior mesenteric artery syndrome, and three with wound dehiscence.ConclusionsThe complication rates in the young pediatric population associated with the off-label use of pedicle screws for spinal fusions are not statistically different from the complication rates associated with the FDA-approved adolescent population.  相似文献   
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Mucoepidermoid carcinoma (MEC) is the most common malignancy of the salivary glands. The clinical behaviour of MEC is largely unpredictable, ranging from indolent tumour growth to highly aggressive metastatic spread. The objective of this study was to determine the clinicopathological predictors of recurrence and survival in patients with head and neck MEC. The medical records of 64 patients who underwent surgical treatment for head and neck MEC between 1982 and 2010 were reviewed. The main outcome measures were disease-free survival (DFS) and overall survival (OS). Clinicopathological parameters evaluated were age, sex, anatomical subsite, histological grade, tumour stage, tumour size, adjuvant therapy, and nodal and margin status. For the entire cohort, the 5-year DFS was 82.8% and the 5-year OS was 67.2%. Histological grade and tumour subsite were statistically significant predictors of OS. Furthermore, tumour stage and nodal status were statistically significant predictors with respect to OS. Advanced tumour stage, high histological grade, submandibular/sublingual localization, and positive nodal status were independent predictors of the prognosis in patients with head and neck MEC. Further studies into the molecular biology of MEC are needed in order to provide new therapeutic strategies for patients with locally aggressive and highly metastatic carcinomas.  相似文献   
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