Flynn Julie, Archer Frank, Morgans Amee
Centre for Ambulance and Paramedic Studies, Monash University, Frankston, Australia.
Prehosp Disaster Med. 2006 Mar-Apr;21(2):72-6. doi: 10.1017/s1049023x00003381.
In Australia, cardiac arrest kills 142 out of every 100,000 people each year; with only 3-4% of out-of-hospital patients with cardiac arrest in Melbourne surviving to hospital discharge. Prompt initiation of cardiopulmonary resuscitation (CPR), defibrillation, and advanced cardiac care greatly improves the chances of survival from cardiac arrest. A critical step in survival is identifying by the emergency ambulance dispatcher potential of the probability that the person is in cardiac arrest. The Melbourne Metropolitan Ambulance Service (MAS) uses the computerized call-taking system, Medical Priority Dispatch System (MPDS), to triage incoming, emergency, requests for ambulance responses. The MPDS is used in many emergency medical systems around the world, however, there is little published evidence of the system's efficacy.
This study attempts to undertake a sensitivity/specificity analysis to determine the ability of MPDS to detect cardiac arrest.
Emergency ambulance dispatch records of all cases identified as suspected cardiac arrest by MPDS were matched with ambulance, patient-care records and records from the Victorian Ambulance Cardiac Arrest Registry to determine the number of correctly identified cardiac arrests. Additionally, cases that had cardiac arrests, but were not identified correctly at the point of call-taking, were examined. All data were collected retrospectively for a three-month period (01 January through 31 March 2003).
The sensitivity of MPDS in detecting cardiac arrest was 76.7% (95% confidence interval (CI): 73.6%-79.8%) and specificity was 99.2% (95% CI: 99.1-99.3%). These results indicate that cardiac arrests are correctly identified in 76.7% of cases.
Although the system correctly identified 76.7% of cardiac arrest cases, the number of false negatives suggests that there is room for improvement in recognition by MPDS to maximize chances for survival in out-of-hospital cardiac arrest. This study provides an objective and comprehensive measurement of the accuracy of MPDS cardiac-arrest detection in Melbourne, as well as providing a baseline for comparison with subsequent changes to the MPDS.
在澳大利亚，每年每10万人中有142人死于心脏骤停；在墨尔本，院外心脏骤停患者中只有3%-4%能存活至出院。及时启动心肺复苏（CPR）、除颤和高级心脏护理可大大提高心脏骤停后的存活几率。生存的关键一步是由急救调度员识别出该人处于心脏骤停状态的可能性。墨尔本都会救护服务局（MAS）使用计算机化的接警系统——医疗优先调度系统（MPDS）对 incoming、emergency、requests for ambulance responses进行分类。MPDS在全球许多紧急医疗系统中都有使用，然而，关于该系统有效性的公开证据很少。
本研究试图进行敏感性/特异性分析，以确定MPDS检测心脏骤停的能力。
将MPDS识别为疑似心脏骤停的所有病例的急救调度记录与救护车、患者护理记录以及维多利亚州救护车心脏骤停登记处的记录进行匹配，以确定正确识别的心脏骤停病例数。此外，还检查了那些发生了心脏骤停但在接警时未被正确识别的病例。所有数据均为回顾性收集，为期三个月（2003年1月1日至3月31日）。
MPDS检测心脏骤停的敏感性为76.7%（95%置信区间（CI）：73.6%-79.8%），特异性为99.2%（95%CI：99.1-99.3%）。这些结果表明，76.7%的病例被正确识别为心脏骤停。
尽管该系统正确识别了76.7%的心脏骤停病例，但假阴性的数量表明，MPDS在识别方面仍有改进空间，以最大限度地提高院外心脏骤停的存活几率。本研究为墨尔本MPDS心脏骤停检测的准确性提供了客观全面的衡量标准，也为与MPDS后续变化进行比较提供了基准。
