Myers R B
Division of Cardiology, Sunnybrook Health Science Centre, North York, Ontario.
Can J Cardiol. 1998 Oct;14(10):1231-40.
To review prehospital management of patients with suspected ST elevation acute myocardial infarction (AMI) based on the acquisition and interpretation of electrocardiograms (ECGs), and the effects of thrombolytic therapy initiated by prehospital care providers.
MEDLINE was searched by combining the search phrases 'thrombolysis,' 'paramedics' and 'myocardial infarction' to identify all pertinent articles. The bibliographies were reviewed to search for other relevant articles.
The earlier that treatment is initiated in AMI, the better the prognosis. Multiple randomized and nonrandomized trials indicate that prehospital care providers (including paramedics, nurses and doctors) are able to acquire prehospital ECGs with negligible increases in on-scene time, ranging from 30 s to 7 mins. With minimal training, they are capable of accurately interpreting ECGs and diagnosing ST elevation AMI, with results comparable with control ECGs obtained by physicians. Numerous studies have investigated the role of specially trained prehospital personnel in initiating thrombolysis. Trials outside of North America have predominantly used physicians, whereas North American studies employed paramedics. Thrombolysis has been shown to be safe and effective when started outside the hospital by physicians or paramedics, with a reduction in time to treatment and no increase in complications. The further a patient with ST elevation AMI is from hospital, the greater the potential benefit of prehospital thrombolysis. The European Myocardial Infarction Project (EMIP), the largest randomized trial of prehospital thrombolysis, demonstrated a trend towards reduced mortality but was underpowered to detect significant mortality differences. The Grampian Region Early Anistreplase Trial (GREAT), a rural study, is the only randomized trial to demonstrate a statistically significant mortality difference in patients receiving prehospital thrombolysis. Despite trends in favour of prehospital diagnosis and treatment of AMI, no urban study has been sufficiently powered to demonstrate mortality benefits.
Prehospital treatment of patients with chest pain using ECGs and thrombolysis is safe. Though rural patients have significant reductions in total mortality when treated with thrombolysis in a prehospital setting, this has not been documented with an urban population. Prehospital identification of thrombolysis-eligible patients with ST elevation AMI via acquisition and interpretation of ECGs followed by triage to a hospital 'lytic team' has the potential to improve patient outcome and requires further investigation. A prehospital paramedic program for identifying and treating thrombolysis-eligible patients requires intensive planning, retrospective feasibility work, implementation and monitoring to establish effectiveness.
基于心电图（ECG）的采集与解读，以及院前急救人员启动溶栓治疗的效果，回顾疑似ST段抬高型急性心肌梗死（AMI）患者的院前管理。
通过组合搜索词“溶栓”“护理人员”和“心肌梗死”检索MEDLINE，以识别所有相关文章。查阅参考文献以搜索其他相关文章。
AMI治疗开始得越早，预后越好。多项随机和非随机试验表明，院前急救人员（包括护理人员、护士和医生）能够采集院前ECG，现场时间增加可忽略不计，从30秒到7分钟不等。经过最少的培训，他们就能准确解读ECG并诊断ST段抬高型AMI，结果与医生获取的对照ECG相当。许多研究调查了经过专门培训的院前人员在启动溶栓治疗中的作用。北美以外的试验主要使用医生，而北美研究则使用护理人员。当由医生或护理人员在院外开始溶栓治疗时，已证明其安全有效，可缩短治疗时间且并发症不增加。ST段抬高型AMI患者离医院越远，院前溶栓的潜在益处就越大。欧洲心肌梗死项目（EMIP）是最大规模的院前溶栓随机试验，显示出死亡率降低的趋势，但检测显著死亡率差异的能力不足。格兰扁地区早期阿尼普酶试验（GREAT）是一项农村研究，是唯一一项在接受院前溶栓治疗的患者中显示出统计学显著死亡率差异的随机试验。尽管有支持AMI院前诊断和治疗的趋势，但尚无城市研究有足够的能力证明其对死亡率的益处。
使用ECG和溶栓对胸痛患者进行院前治疗是安全的。虽然农村患者在院前接受溶栓治疗时总死亡率显著降低，但城市人群尚未有相关记录。通过采集和解读ECG，然后将符合溶栓条件的ST段抬高型AMI患者分诊到医院“溶栓团队”进行院前识别，有可能改善患者预后，需要进一步研究。一个用于识别和治疗符合溶栓条件患者的院前护理人员项目需要精心规划、回顾性可行性研究、实施和监测以确定其有效性。
