Arrich Jasmin, Holzer Michael, Havel Christof, Müllner Marcus, Herkner Harald
Department of Emergency Medicine, Medical University of Vienna, Vienna, Austria.
Cochrane Database Syst Rev. 2012 Sep 12(9):CD004128. doi: 10.1002/14651858.CD004128.pub3.
Good neurologic outcome after cardiac arrest is hard to achieve. Interventions during the resuscitation phase and treatment within the first hours after the event are critical. Experimental evidence suggests that therapeutic hypothermia is beneficial, and a number of clinical studies on this subject have been published. This review was originally published in 2009.
We performed a systematic review and meta-analysis to assess the effectiveness of therapeutic hypothermia in patients after cardiac arrest. Neurologic outcome, survival and adverse events were our main outcomes. We aimed to perform individual patient data analysis, if data were available, and to form subgroups according to the cardiac arrest situation.
We searched the following databases: the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2001, Issue 7); MEDLINE (1971 to July 2011); EMBASE (1987 to July 2011); CINAHL (1988 to July 2011); PASCAL (2000 to July 2011); and BIOSIS (1989 to July 2011). The original search was performed in January 2007.
We included all randomized controlled trials assessing the effectiveness of therapeutic hypothermia in patients after cardiac arrest, without language restrictions. Studies were restricted to adult populations cooled with any cooling method, applied within six hours of cardiac arrest.
Validity measures, the intervention, outcomes and additional baseline variables were entered into a database. Meta-analysis was only done for a subset of comparable studies with negligible heterogeneity. For these studies, individual patient data were available.
We included four trials and one abstract reporting on 481 patients in the systematic review. The updated search resulted in no new studies to include. Quality of the included studies was good in three out of five studies. For the three comparable studies on conventional cooling methods all authors provided individual patient data. With conventional cooling methods, patients in the hypothermia group were more likely to reach a best cerebral performance categories (CPC) score of one or two (five point scale: 1 = good cerebral performance, to 5 = brain death) during the hospital stay (individual patient data; RR 1.55; 95% CI 1.22 to 1.96) and were more likely to survive to hospital discharge (individual patient data; RR 1.35; 95% CI 1.10 to 1.65) compared to standard post-resuscitation care. Across all studies, there was no significant difference in reported adverse events between hypothermia and control.
AUTHORS' CONCLUSIONS: Conventional cooling methods to induce mild therapeutic hypothermia seem to improve survival and neurologic outcome after cardiac arrest. Our review supports the current best medical practice as recommended by the International Resuscitation Guidelines.
心脏骤停后实现良好的神经功能预后很难。复苏阶段的干预措施以及事件发生后最初数小时内的治疗至关重要。实验证据表明治疗性低温有益，并且已经发表了许多关于这一主题的临床研究。本综述最初发表于2009年。
我们进行了一项系统评价和荟萃分析，以评估治疗性低温对心脏骤停后患者的有效性。神经功能预后、生存率和不良事件是我们的主要结局。如果有可用数据，我们旨在进行个体患者数据分析，并根据心脏骤停情况形成亚组。
我们检索了以下数据库：Cochrane对照试验中心注册库（CENTRAL）（《Cochrane图书馆》2001年第7期）；MEDLINE（1971年至2011年7月）；EMBASE（1987年至2011年7月）；护理学与健康领域数据库（CINAHL）（1988年至2011年7月）； Pascal数据库（2000年至2011年7月）；以及生物学文摘数据库（BIOSIS）（1989年至2011年7月）。最初的检索于2007年1月进行。
我们纳入了所有评估治疗性低温对心脏骤停后患者有效性的随机对照试验，无语言限制。研究仅限于在心脏骤停后6小时内采用任何降温方法进行降温的成年人群。
将效度指标、干预措施、结局和其他基线变量录入数据库。仅对异质性可忽略不计的可比研究子集进行荟萃分析。对于这些研究，有个体患者数据可用。
我们在系统评价中纳入了4项试验和1篇关于481例患者的摘要报告。更新后的检索未发现新的研究可纳入。纳入研究的质量在5项研究中有3项良好。对于3项关于传统降温方法的可比研究，所有作者均提供了个体患者数据。采用传统降温方法时，与标准的复苏后护理相比，低温治疗组患者在住院期间更有可能达到脑功能最佳分级（CPC）评分1或2（五分制：1 = 脑功能良好，至5 = 脑死亡），并且更有可能存活至出院（个体患者数据；RR 1.35；95%CI 1.10至1.65）。在所有研究中，低温治疗组和对照组报告的不良事件之间无显著差异。
采用传统降温方法诱导轻度治疗性低温似乎可改善心脏骤停后的生存率和神经功能预后。我们的综述支持国际复苏指南推荐的当前最佳医疗实践。
