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81.
A method for initiating quality assurance in cardiac surgery was developed multicentrically by a commission of the German Society for Thoracic and Cardiovascular Surgery (QUADRA Study). To appraise the quality of cardiosurgical action, variables were compiled from the preoperative, intraoperative, and postoperative treatment course. The data collection was carried out at the same time as treatment. On the basis of unicentric data profiles, multicentric hospital profiles, and problem profiles, a quality comparison could be carried out and the variability of cardiosurgical action which may occasion interventions could be identified. A reduction of perioperative blood consumption during the study period could be observed in four out of five hospitals as the first result. The data collection also revealed epidemiological features. On average, women were older than men at the time of the heart-valve and coronary operations. To ensure data validity and the organization of quality assurance, a documentation assistant and a specially trained physician are necessary at every cardiovascular surgery center. The multicentric external comparison is indispensable and must be carried out by means of a central data collection, for which intrumental and staff capacities are also to be provided. With modern methods of data processing, an additional and new approach to the improvement of quality in cardiac surgery can thus be made.  相似文献   
82.
OBJECTIVES: The purpose of this study was to evaluate the hypothesis that presumed reversion of electrical remodeling after cardioversion of atrial fibrillation (AF) restores the efficacy of flecainide. BACKGROUND: Flecainide loses its efficacy to cardiovert when AF has been present for more than 24 hours. Most probably, the loss is caused by atrial electrical remodeling. Studies suggest electrical remodeling is completely reversible within 4 days after restoration of sinus rhythm (SR). METHODS: One hundred eighty-one patients with persistent AF (median duration 3 months) were included in this prospective study. After failure of pharmacologic cardioversion by flecainide 2 mg/kg IV (maximum 150 mg in 10 minutes) and subsequent successful electrical cardioversion, we performed intense transtelephonic rhythm monitoring three times daily for 1 month. In case of AF recurrence, a second cardioversion by flecainide was attempted as soon as possible. RESULTS: AF recurred in 123 patients (68%). Successful cardioversion by flecainide occurred only when SR had been maintained for more than 4 days (7/51 patients [14%]). Failure to cardiovert was associated with a prolonged duration of the recurrent AF episode and concurrent digoxin use. Multivariate logistic regression confirmed that successful cardioversion was determined by digoxin use (odds ratio [OR] 0.093, P = .047) and by the interaction between the duration of SR and the (inverse) duration of recurrent AF (OR 6.499, P < .001). When flecainide was administered within 10 hours after AF onset and the duration of SR was greater than 4 days, the success rate was 58%. CONCLUSIONS: Flecainide recovers its antiarrhythmic action after cardioversion of AF. However, successful pharmacologic cardioversion occurs only after SR has lasted at least 4 days and is expected only for recurrences having duration of a few hours. Immediate pharmacologic cardioversion of AF recurrence may be a worthwhile strategy for management of persistent AF.  相似文献   
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ObjectiveThis retrospective study evaluates the occurrence and frequency of different fracture patterns in a series of computed tomography (CT) scans in terms of the AOCMF Trauma Classification (TC) orbit module and correlates the assigned defects with measurements of the fracture area in order to get an approximate guideline for fracture size predictions on the basis of the classification.Material and methodsCT scans of patients with orbital floor fractures were evaluated using the AOCMFTC to determine the topographical subregions. The coding consisted of: W = orbital wall, 1 = anterior orbit, 2 = midorbit, i = inferior, m = medial. The 3-dimensional surface area size of the fractures was quantified by the “defect body” method (Brainlab, Munich, Germany). The fracture area size and its confidence and prediction interval within each topographical subregion was estimated by regression analysis.ResultsA total of 137 CT scans exhibited 145 orbital floor fractures, which were combined with 34 medial orbital wall fractures in 31 patients. The floor fractures – W1(i)2(i) (n = 86) and W1(i) (n = 19) were the most frequent patterns. Combined floor and medial wall fractures most frequently corresponded to the pattern W1 (im)2 (im) (n = 15) ahead of W1 (im) 2(i) (n = 10). The surface area size ranged from 0.11 cm2 to 6.09 cm2 for orbital floor and from 0.29 cm2 to 5.43 cm2 for medial wall fractures.The prediction values of the mean fracture area size within the subregions were computed as follows: W1(i) = 2.25 cm2, W2(i) = 1.64 cm2, W1(i)2(i) = 3.10 cm2, W1(m) = 1.36 cm2, W2(m) = 1.65 cm2, W1(m)2(m) = 2.98 cm2, W1 (im) = 3.35 cm2, W1 (im) 2(i) = 4.63 cm2, W1 (im)2(m) = 4.06 cm2 and W1 (im)2 (im) = 7.16 cm2.ConclusionThe AOCMFTC orbital module offers a suitable framework for topographical allocation of fracture patterns inside the infero-medial orbital cavity. The involvement of the subregions is of predictive value providing estimations of the mean 3-D fracture area size.  相似文献   
86.

Introduction

Fast track methodology or enhanced recovery schemes have gained increasing popularity in perioperative care. While evidence is strong for colorectal surgery, its importance in gastric and oesophageal surgery has yet to be established. This article reviews the evidence of enhanced recovery schemes on outcome for this type of surgery.

Methods

A systematic literature search was conducted up to March 2014. Studies were retrieved and analysed using predetermined criteria.

Results

From 34 articles reviewed, 18 eligible studies were identified: 7 on gastric and 11 on oesophageal resection. Three randomised controlled trials, five case-controlled studies and ten case series were identified. The reported protocols included changes to each stage of the patient journey from pre to postoperative care. The specific focus following oesophageal resections was on early mobilisation, a reduction in intensive care unit stay, early drain removal and early (or no) contrast swallow studies. Following gastric resections, the emphasis was on reducing epidural anaesthesia along with re-establishing oral intake in the first three postoperative days and early removal of nasogastric tubes.In the papers reviewed, mortality rates following fast track surgery were 0.8% (9/1,075) for oesophageal resection and 0% (0/329) for gastric resection. The reported morbidity rate was 16.5% (54/329) following gastric resection and 38.6% (396/1,075) following oesophageal resection. Length of stay was reduced in both groups compared with conventional recovery groups in comparative studies.

Conclusions

The evidence for enhanced recovery schemes following gastric and oesophageal resection is weak, with only three (low volume) published randomised controlled trials. However, the enhanced recovery approach appears safe and may be associated with a reduction in length of stay.  相似文献   
87.
Mimuro  J; Schleef  RR; Loskutoff  DJ 《Blood》1987,70(3):721-728
The extracellular matrix (ECM) of cultured bovine aortic endothelial cells (BAEs) was analyzed by immunoblotting and reverse fibrin autography and shown to contain type 1 plasminogen activator inhibitor (PAI-1). Most PAI-1 in the ECM formed complexes with exogenously added tissue-type plasminogen activator (tPA), demonstrating that this PAI-1 was functionally active. The resulting tPA/PAI-1 complexes were recovered in the reaction solution, indicating that the PAI-1 in such complexes no longer bound to ECM. The PAI-1 could not be removed by incubating ECM in high salt (2 mol/L NaCl), sugars (1 mol/L galactose, 1 mol/L mannose), glycosaminoglycans (10 mmol/L heparin, 10 mmol/L dermatan sulfate), or epsilon-aminocaproic acid (0.1 mol/L). However, PAI-1 could be extracted from ECM by treatment with either arginine (0.5 mol/L) or potassium thiocyanate (2 mol/L), or by incubation under acidic conditions (pH 2.5). ECM depleted of PAI-1 by acid extraction was able to bind both the active and latent forms of PAI-1. In this instance, most of the bound PAI-1 did not form complexes with tPA, indicating that the latent form was not activated as a consequence of binding to ECM. Although the PAI-1 activity in conditioned medium decayed with a half-life (t 1/2) of less than 3 hours, the t 1/2 of ECM- associated PAI-1 was greater than 24 hours. These data suggest that PAI- 1 is produced by cultured BAEs in an active form and is then either released into the medium where it is rapidly inactivated or into the subendothelium where it binds to ECM. The specific binding of PAI-1 to ECM protects it from this inactivation.  相似文献   
88.
Warrell  RP Jr; Lee  BJ; Kempin  SJ; Lacher  MJ; Straus  DJ; Young  CW 《Blood》1981,57(6):1011-1014
We treated 51 patients with advanced malignant lymphoma refractory to conventional therapy with methyl-glyoxal-bis(guanylhydrazone) (methyl- GAG) at doses ranging from 400 to 800 mg/sq m. Therapy was started on a weekly schedule and was switched to every other week in responding patients at the onset of toxicity. Partial responses were observed in 6 of 13 evaluable patients with Hodgkin's disease (46%), 5 of 10 patients with diffuse poorly differentiated lymphocytic lymphoma (50%), 2 of 4 patients with nodular poorly differentiated lymphocytic lymphoma (50%), and 3 of 13 patients with diffuse histiocytic lymphoma (23%). Two of six patients with mycosis fungoides showed objective improvement in cutaneous disease. Toxicity was generally mild and included muscular weakness, myalgia, mucositis, and diarrhea; two patients developed bronchospasm following drug infusions. We conclude that methyl-GAG has major antitumor activity when administered on this schedule to patients with advanced malignant lymphoma. The low degree of toxicity, unique mechanism of action, and minimal myelosuppressive effects suggest that methyl-GAG will prove useful in future trials of combination chemotherapy regimens for the treatment of lymphoma.  相似文献   
89.
Eosinophils stimulate fibroblast DNA synthesis   总被引:9,自引:0,他引:9  
Pincus  SH; Ramesh  KS; Wyler  DJ 《Blood》1987,70(2):572-574
Fibrosis complicates a number of chronic inflammatory diseases and occurs in some conditions following chronic hypereosinophilic syndromes. We assessed whether eosinophils might be a source of fibrogenic factors. Extracts of human and guinea pig cell populations enriched for eosinophils contained substances that stimulated tritiated thymidine incorporation by human fibroblasts. Supernatants derived from resting eosinophils and extracts prepared from eosinophil granules also contained fibrogenic factors. Our findings demonstrate a new potential role for eosinophils and suggest a causal relationship between tissue eosinophilia and scar formation in certain parasitic conditions.  相似文献   
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