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排序方式: 共有471条查询结果,搜索用时 15 毫秒
1.
The need to evaluate expensive, dramatic, and politically sensitive emergency medical services programs when classical controlled trials are neither ethically nor practically possible can be satisfied by quasi-experimental designs. The sequential implementation of paramedic services in several suburban areas provided a natural experimental situation in which to evaluate whether addition of the service could significantly alter the outcome of cardiac emergencies compared to the basic emergency medical technician program previously available. Before measurements and after measurements were made in a study area plus two control areas: one with paramedic services in both time periods and the other with emergency medical technician service throughout. Preliminary results indicate successful resuscitation increased from 20% to 32% (p less than .05) and discharge from the hospital went from 8% to 18% (p less than .01). The implications for program and policy decisions are noted. Development of studies that evolved from this work are outlined. 相似文献
2.
Patrick H. Pun Sana M. Al-Khatib Joo Yoon Han Rex Edwards Gust H. Bardy J. Thomas Bigger Alfred E. Buxton Arthur J. Moss Kerry L. Lee Richard Steinman Paul Dorian Al Hallstrom Riccardo Cappato Alan H. Kadish Peter J. Kudenchuk Daniel B. Mark Paul L. Hess Lurdes Y.T. Inoue Gillian D. Sanders 《American journal of kidney diseases》2014
3.
DK Bilku AR Dennison TC Hall MS Metcalfe G Garcea 《Annals of the Royal College of Surgeons of England》2014,96(1):15-22
INTRODUCTION
Surgical stress in the presence of fasting worsens the catabolic state, causes insulin resistance and may delay recovery. Carbohydrate rich drinks given preoperatively may ameliorate these deleterious effects. A systematic review was undertaken to analyse the effect of preoperative carbohydrate loading on insulin resistance, gastric emptying, gastric acidity, patient wellbeing, immunity and nutrition following surgery.METHODS
All studies identified through PubMed until September 2011 were included. References were cross-checked to ensure capture of cited pertinent articles.RESULTS
Overall, 17 randomised controlled trials with a total of 1,445 patients who met the inclusion criteria were identified. Preoperative carbohydrate drinks significantly improved insulin resistance and indices of patient comfort following surgery, especially hunger, thirst, malaise, anxiety and nausea. No definite conclusions could be made regarding preservation of muscle mass. Following ingestion of carbohydrate drinks, no adverse events such as apparent or proven aspiration during or after surgery were reported.CONCLUSIONS
Administration of oral carbohydrate drinks before surgery is probably safe and may have a positive influence on a wide range of perioperative markers of clinical outcome. Further studies are required to determine its cost effectiveness. 相似文献4.
5.
The effect of a zinc metalloprotease from Serratia marcescens on platelet surface glycoproteins (GP) Ib and V was analyzed. Increasing protease treatments caused progressive loss of GP Ib with appearance of the major fragment, glycocalicin, in the supernatant solution. No GP V was detected in the supernatant solution, and protease-pretreated platelets had the same capacity as control platelets to release fragment 1 of GP V in response to thrombin. The Serratia protease- pretreated platelets did show the lag before thrombin-induced dense granule secretion, characteristic of platelets modified by pretreatment with other nonstimulating proteases. Treatment with Serratia protease gives the only demonstrated selective loss of GP Ib without apparent effect on GP V. It suggests that GP V (1) does not depend on GP Ib for its association with platelets and (2) is not the substrate for protease modification of platelet function. 相似文献
6.
7.
Survivors of out-of-hospital ventricular fibrillation (VF) are at high risk for recurrent VF, probably reflecting continued myocardial electrical instability. In this study 12-lead ECGs of 125 VF survivors with coronary heart disease were examined and compared to those of 98 ambulatory post-MI patients. The study was part of an effort to define clinical identifiers of patients likely to develop sudden cardiac death. Ventricular fibrillation survivors were commonly had premature ventricular complexes (PVCs):30% versus 13% (P less than 0.01). In addition, ECGs of VF survivors showed a significantly greater prevalence of ST-segment depression (46% versus 10%), T wave flattening (52% versus 26%), and QTc prolongation (35% versus 18%). It is proposed that these repolarization abnormalities represent asynchronous repolarization, which together with frequent PVCs, may set the stage for re-entrant ventricular dysrhythmias and ultimately VF. It is also possible that repolarization abnormalities together with premature ventricular contractions might serve as markers of patients with coronary heart disease who are at increased risk for sudden cardiac death. 相似文献
8.
W D Weaver M S Eisenberg J S Martin P E Litwin S M Shaeffer M T Ho P Kudenchuk A P Hallstrom M D Cerqueira M K Copass 《Journal of the American College of Cardiology》1990,15(5):925-931
Prehospital initiation of thrombolytic therapy by paramedics, if both feasible and safe, could considerably reduce the time to treatment and possibly decrease the extent of myocardial necrosis in patients with acute coronary thrombosis. Preliminary to a trial of such a treatment strategy, paramedics evaluated the characteristics of 2,472 patients with chest pain of presumed cardiac origin; 677 (27%) had suitable clinical findings consistent with possible acute myocardial infarction and no apparent risk of complication for potential thrombolytic drug treatment. Electrocardiograms (ECGs) of 522 of the 677 patients were transmitted by cellular telephone to a base station physician; 107 (21%) of the tracings showed evidence of ST segment elevation. Of the total 2,472 patients, 453 developed evidence of acute myocardial infarction in the hospital; 163 (36%) of the 453 had met the strict prehospital screening history and examination criteria and 105 (23.9%) showed ST elevation on the ECG and, thus, would have been suitable candidates for prehospital thrombolytic treatment if it had been available. The average time from the onset of chest pain to prehospital diagnosis was 72 +/- 52 min (median 52); this was 73 +/- 44 min (median 62) earlier than the time when thrombolytic treatment was later started in the hospital. Paramedic selection of appropriate patients for potential prehospital initiation of thrombolytic treatment is feasible with use of a directed checklist and cellular-transmitted ECG and saves time. This strategy may reduce the extent and complications of infarction compared with results that can be achieved in a hospital setting. 相似文献
9.
C M Pratt A Hallstrom P Theroux D Romhilt J Coromilas J Myles 《Journal of the American College of Cardiology》1991,17(1):1-8
The Cardiac Arrhythmia Pilot Study (CAPS) was a 1 year trial that analyzed the safety and effectiveness of arrhythmia suppression in 502 patients surviving acute myocardial infarction who had greater than or equal to 10 ventricular premature depolarizations/h or greater than or equal to 5 runs of ventricular tachycardia on a Holter recording obtained 6 to 60 days after the acute infarction. Because 100 of these patients received placebo in a double-blind fashion for 1 year, a comprehensive objective analysis was performed of spontaneous arrhythmia changes based on real data rather than statistical estimates. In the CAPS placebo group, 19% developed some serious clinical event in 1 year (death, heart failure, proarrhythmia) that could likely be attributable to antiarrhythmic drug toxicity. A significant reduction in the frequency of ventricular premature depolarizations (p = 0.004) occurred in the first few weeks of "therapy" with a further significant (p less than 0.04) decrease between 3 to 12 months. After initiation of placebo antiarrhythmic therapy, 27% had "apparent ventricular premature depolarization suppression" (greater than or equal to 70% reduction) after one Holter recording evaluation and nearly half (48%) after six Holter recordings to assess suppression were performed.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
10.
Koulnis M Porpiglia E Porpiglia PA Liu Y Hallstrom K Hidalgo D Socolovsky M 《Blood》2012,119(5):1228-1239
Survival signaling by the erythropoietin (Epo) receptor (EpoR) is essential for erythropoiesis and for its acceleration in hypoxic stress. Several apparently redundant EpoR survival pathways were identified in vitro, raising the possibility of their functional specialization in vivo. Here we used mouse models of acute and chronic stress, including a hypoxic environment and β-thalassemia, to identify two markedly different response dynamics for two erythroblast survival pathways in vivo. Induction of the antiapoptotic protein Bcl-x(L) is rapid but transient, while suppression of the proapoptotic protein Bim is slower but persistent. Similar to sensory adaptation, however, the Bcl-x(L) pathway "resets," allowing it to respond afresh to acute stress superimposed on a chronic stress stimulus. Using "knock-in" mouse models expressing mutant EpoRs, we found that adaptation in the Bcl-x(L) response occurs because of adaptation of its upstream regulator Stat5, both requiring the EpoR distal cytoplasmic domain. We conclude that survival pathways show previously unsuspected functional specialization for the acute and chronic phases of the stress response. Bcl-x(L) induction provides a "stop-gap" in acute stress, until slower but permanent pathways are activated. Furthermore, pathologic elevation of Bcl-x(L) may be the result of impaired adaptation, with implications for myeloproliferative disease mechanisms. 相似文献