使用地理信息系统建立院外心脏骤停延迟救护车反应的呼入量与无法响应间隔时间的关联模型。

A model for the association of the call volume and the unavailable-for-response interval on the delayed ambulance response for out-of-hospital cardiac arrest using a geographic information system.

机构信息

The Center for Education and Training of EMS and Rescue (KOA), Seoul Fire Academy, Seoul, Republic of Korea.

出版信息

Prehosp Emerg Care. 2010 Oct-Dec;14(4):469-76. doi: 10.3109/10903127.2010.497895.

DOI:10.3109/10903127.2010.497895

PMID:20809689

Abstract

BACKGROUND

An optimal ambulance response interval is desirable for emergency medical services (EMS) operations. Arriving on scene within a treatment time window is often delayed for many reasons, including overwhelming call volume.

OBJECTIVE

To determine whether an association exists between the ambulance call volume (ACV), the unavailable-for-response (UFR) interval, and the delayed ambulance response for out-of-hospital cardiac arrest (OHCA) patients.

METHODS

This was a retrospective observational study conducted in Seoul, Republic of Korea. The EMS ambulance logs from the metropolitan city's 22 EMS agencies, from January 1, 2006, to June 30, 2007, were obtained from the National Emergency Management Agency. These data included patient demographics and call location addresses. The addresses of the call locations and ambulance stations were geocoded and configured with a polygon expressing the optimal coverage areas in which an ambulance could travel within 4 minutes from their base station. The median ACV and mean UFR interval of each EMS agency were calculated. An actual response time interval greater than 4 minutes compared with the optimal coverage area was defined as a suboptimal response. Potential influencing factors on suboptimal response were analyzed using a multivariate logistic regression model to calculated the odds ratio (OR) and 95% confidence interval (95% CI).

RESULTS

Geocoding was successful for 255,961 calls, and 3,644 cardiac arrests occurred within the configured optimal response coverage areas. The response rate intervals for cardiac arrest patients, however, were optimal in only 22.6% of calls. Influencing factors for suboptimal response (occurring in 77.4% of the cases) were the median ACV and the mean UFR interval of each EMS agency. When the median ACV was seven or more, the OR of suboptimal response was 1.407 (1.142-1.734). If the mean UFR interval was 55 minutes or more, the OR for suboptimal response was 1.770 (1.345-2.329).

CONCLUSION

The ambulance response time intervals in this study setting were associated with EMS agencies with higher ACVs and longer UFR intervals.

摘要

背景

对于紧急医疗服务（EMS）运营来说，理想的救护车响应时间间隔是可取的。由于各种原因，包括呼叫量过大，救护车往往会延误到达治疗时间窗口。

目的

确定救护车呼叫量（ACV）、不可用响应（UFR）间隔与院外心脏骤停（OHCA）患者的救护车延迟响应之间是否存在关联。

方法

这是一项在韩国首尔进行的回顾性观察研究。从国家应急管理局获得了大都市 22 个 EMS 机构从 2006 年 1 月 1 日至 2007 年 6 月 30 日的 EMS 救护车日志。这些数据包括患者人口统计学信息和呼叫地点地址。呼叫地点和救护车站的地址进行了地理编码，并配置了一个多边形，表达了救护车可以在从其基站出发的 4 分钟内行驶的最佳覆盖区域。计算了每个 EMS 机构的中位数 ACV 和平均 UFR 间隔。与最佳覆盖区域相比，实际响应时间间隔大于 4 分钟被定义为次优响应。使用多变量逻辑回归模型分析对次优响应有潜在影响的因素，以计算比值比（OR）和 95%置信区间（95%CI）。

结果

255961 次呼叫成功进行了地理编码，配置的最佳响应覆盖区域内发生了 3644 次心脏骤停。然而，只有 22.6%的呼叫的反应时间间隔是最佳的。次优响应（占 77.4%的病例）的影响因素是每个 EMS 机构的中位数 ACV 和平均 UFR 间隔。当中位数 ACV 为 7 或更多时，次优响应的 OR 为 1.407（1.142-1.734）。如果平均 UFR 间隔为 55 分钟或更长，则次优响应的 OR 为 1.770（1.345-2.329）。