University of Western Australia, Crawley, Perth, Australia.
Prehosp Emerg Care. 2013 Apr-Jun;17(2):261-73. doi: 10.3109/10903127.2012.749967. Epub 2013 Feb 1.
Acute respiratory failure (ARF) is a common problem encountered by emergency medical services and is associated with significant morbidity, mortality, and health care costs. Continuous positive airway pressure (CPAP) is an integral part of the hospital treatment of acute ARF, predominantly because of congestive heart failure. Intuitively, better patient outcomes may be achieved when CPAP is applied early in the prehospital setting, but there are few outcome studies to validate its use in this setting.
This systematic review and meta-analysis aimed to examine the effectiveness of CPAP in the prehospital setting for patients with ARF.
A literature review of bibliographic databases and secondary sources was conducted and potential papers were assessed by two independent reviewers. Included studies were those that compared CPAP therapy (and usual care) with no CPAP for ARF in the prehospital setting. Studies of other methods of noninvasive ventilation were not included. Methodologic quality was assessed using guidelines from the Cochrane Collaboration. Outcomes included the number of intubations, mortality, physiologic parameters, and dyspnea score. Forrest plots were constructed to estimate the pooled effect of CPAP on outcomes.
Five studies (1,002 patients) met the selection criteria--three randomized controlled trials (RCTs), a nonrandomized comparative study, and a retrospective comparative study using chart review. Forty-seven percent of the patients were allocated to the CPAP group. Baseline characteristics were similar between groups. The pooled estimates demonstrated significantly fewer intubations (odds ratio [OR] 0.31; 95% confidence interval [CI] 0.19-0.51) and lower mortality (OR 0.41; 95% CI 0.19-0.87) in the CPAP group.
The studies included in this review showed a reduction in the number of intubations and mortality in patients with ARF who received CPAP in the prehospital setting. The results may not be applicable to other health care contexts because of the inherent differences in the organization and staffing of the EMS systems. Information from large RCTs on the efficacy of CPAP initiated early in the prehospital setting is critical to establishing the evidence base underpinning this therapy before ambulance services incorporate CPAP as routine clinical practice.
急性呼吸衰竭（ARF）是急诊医疗服务中常见的问题，与较高的发病率、死亡率和医疗保健费用相关。持续气道正压通气（CPAP）是急性 ARF 医院治疗的一个重要组成部分，主要是因为充血性心力衰竭。直观地说，当 CPAP 在院前环境中尽早应用时，可能会获得更好的患者预后，但很少有研究来验证其在这种环境中的应用。
本系统评价和荟萃分析旨在检查 CPAP 在 ARF 的院前环境中的有效性。
对文献数据库和二次来源进行了文献回顾，由两名独立的审查员评估潜在的论文。纳入的研究是那些将 CPAP 治疗（和常规护理）与 ARF 院前环境中的无 CPAP 治疗进行比较的研究。不包括其他无创通气方法的研究。使用 Cochrane 协作组织的指南评估方法学质量。结果包括插管数量、死亡率、生理参数和呼吸困难评分。构建森林图来估计 CPAP 对结果的 pooled 效应。
五项研究（1002 例患者）符合选择标准——三项随机对照试验（RCT）、一项非随机对照研究和一项使用图表回顾的回顾性对照研究。47%的患者被分配到 CPAP 组。组间基线特征相似。pooled 估计表明 CPAP 组的插管数量显著减少（比值比 [OR] 0.31；95%置信区间 [CI] 0.19-0.51）和死亡率降低（OR 0.41；95% CI 0.19-0.87）。
本综述纳入的研究表明，在 ARF 患者中，院前环境中接受 CPAP 治疗的患者插管数量和死亡率降低。由于 EMS 系统的组织和人员配备存在固有差异，这些结果可能不适用于其他医疗保健环境。关于在院前环境中尽早开始 CPAP 的疗效的大型 RCT 提供的信息对于在救护车服务将 CPAP 纳入常规临床实践之前，为支持该治疗的证据基础奠定基础至关重要。
