Background: Despite recent advances, the average survival after out-of-hospital cardiac arrest (OHCA) remains <10%. Early defibrillation by an automated external defibrillator is the most important intervention for patients with OHCA, showing survival proportions >50%. Accordingly, placement of automated external defibrillators in the community as part of a public access defibrillation program (PAD) is recommended by international guidelines. However, different strategies have been proposed on how exactly to increase and make use of publicly available automated external defibrillators. This systematic review aimed to evaluate the effect of PAD and the different PAD strategies on survival after OHCA.

Methods: PubMed, Embase, and the Cochrane Library were systematically searched on August 31, 2015 for observational studies reporting survival to hospital discharge in OHCA patients where an automated external defibrillator had been used by nonemergency medical services. PAD was divided into 3 groups according to who applied the defibrillator: nondispatched lay first responders, professional first responders (firefighters/police) dispatched by the Emergency Medical Dispatch Center (EMDC), or lay first responders dispatched by the EMDC.

Results: A total of 41 studies were included; 18 reported PAD by nondispatched lay first responders, 20 reported PAD by EMDC-dispatched professional first responders (firefighters/police), and 3 reported both. We identified no qualified studies reporting survival after PAD by EMDC-dispatched lay first responders. The overall survival to hospital discharge after OHCA treated with PAD showed a median survival of 40.0% (range, 9.1–83.3). Defibrillation by nondispatched lay first responders was associated with the highest survival with a median survival of 53.0% (range, 26.0–72.0), whereas defibrillation by EMDC-dispatched professional first responders (firefighters/police) was associated with a median survival of 28.6% (range, 9.0–76.0). A meta-analysis of the different survival outcomes could not be performed because of the large heterogeneity of the included studies.

Conclusions: This systematic review showed a median overall survival of 40% for patients with OHCA treated by PAD. Defibrillation by nondispatched lay first responders was found to correlate with the highest impact on survival in comparison with EMDC-dispatched professional first responders. PAD by EMDC-dispatched lay first responders could be a promising strategy, but evidence is lacking.

背景：尽管有最近的进展，但院外心脏骤停（OHCA）后的平均存活率仍<10％。对于OHCA患者，通过自动体外除颤器进行早期除颤是最重要的干预措施，其生存率> 50％。因此，国际准则建议将自动体外除颤器作为公共除颤程序（PAD）的一部分放置在社区中。然而，已经提出了关于如何精确地增加和利用公开可用的自动体外除颤器的不同策略。本系统综述旨在评估PAD和不同PAD策略对OHCA术后生存的影响。

方法： 2015年8月31日，系统地搜索PubMed，Embase和Cochrane图书馆以进行观察性研究，以报告非紧急医疗服务使用自动体外除颤器的OHCA患者的出院存活率。PAD根据使用除颤器的人分为三类：未派遣的急救人员，紧急医疗调度中心（EMDC）派遣的专业急救人员（消防员/警察）或EMDC派遣的非急救人员。

结果：共纳入41项研究；18个报告了未派遣的急救人员的PAD，20个报告了EMDC派遣的专业急救人员（消防员/警察）的PAD，还有3个都报告了。我们没有发现合格的研究报告了由EMDC派遣的急救人员进行PAD后的存活情况。用PAD进行OHCA治疗后，到出院的总生存期中位生存率为40.0％（范围9.1–83.3）。未分派的急救人员的除颤与最高生存率相关，中位生存率为53.0％（范围26.0–72.0），而由EMDC派遣的专业急救人员（消防员/警察）进行的除纤颤，中位生存率为28.6％。 （范围为9.0–76.0）。

结论：该系统评价显示，PAD治疗的OHCA患者的平均总生存率为40％。与EMDC派遣的专业急救员相比，未派遣的非急救员进行的除颤与生存率的最高影响相关。由EMDC派遣的急救人员进行PAD可能是一种有前途的策略，但缺乏证据。