导语：
术后谵妄是手术患者常见的并发症，而术中脑电爆发抑制现象可能与术后谵妄的发生有关。本文将通过一项系统综述和Meta分析，探讨术中脑电爆发抑制与术后谵妄之间的关联。
一、研究背景
术后谵妄是一种常见的术后认知功能障碍，它不仅影响患者的恢复，还可能增加并发症和死亡率。术中脑电爆发抑制是麻醉过程中的一种脑电图模式，有研究表明这种模式可能与术后谵妄的发生有关。然而，相关研究的结果并不一致。为此，本研究旨在通过系统综述和Meta分析，评估术中脑电爆发抑制与术后谵妄之间的关联。
二、研究方法
本研究对PubMed、MEDLINE、Embase、Google Scholar和Cochrane中央对照试验注册库进行了系统搜索，并在2023年5月进行了更新。纳入的研究包括队列研究、病例对照研究和随机对照研究，这些研究报道了接受全身麻醉的成人手术患者术中脑电爆发抑制与术后谵妄发生率的关联。主要结局是术中脑电爆发抑制患者与无爆发抑制患者术后谵妄的合并优势比（OR）。数据由两名独立研究者提取。研究方案已在PROSPERO注册（注册号：CRD42022326479），结果按照PRISMA指南报告。
三、研究结果
共纳入14项研究（6435名患者）进行分析。术后谵妄的总发生率为21.1%（1358/6435）。与无术中脑电爆发抑制的患者相比，有术中脑电爆发抑制的患者术后谵妄的发生率更高（合并OR，1.492；95%置信区间[1.022-2.178]；I2 = 44%；95% CI [0%-75%]；τ2 = 0.110）。术后谵妄患者术中脑电爆发抑制的持续时间显著更长（标准化均数差[SMD] 0.462 [95% CI, 0.293-0.632]；I2 = 63%；95% CI [16%-84%]；τ2 = 0.027）。谵妄组脑电爆发抑制比率显著更高（SMD 0.150；95% CI [0.055-0.245]；I2 = 0%；95% CI [0%-85%]；τ2 = 0.00）。
四、研究结论
我们的Meta分析表明，术中脑电爆发抑制与术后谵妄之间存在关联，但证据质量非常低。由于纳入研究数量有限，且研究之间存在显著异质性，因此强调了需要进一步的高质量研究来建立更可靠的结论。
总结：
本研究为术中脑电爆发抑制与术后谵妄之间的关联提供了证据，但鉴于证据质量的限制，未来仍需更多研究来确认这一关联，并探索其潜在的机制。对于临床医生而言，监测术中脑电爆发抑制现象可能有助于识别术后谵妄的高风险患者，从而采取相应的预防措施。
原文摘要
Association between intraoperative electroencephalogram burst suppression and postoperative delirium: A systematic review and meta-analysis
Background: Electroencephalogram burst suppression can be associated with postoperative delirium; however, the results of relevant studies are discrepant. This systematic review and meta-analysis aimed to assess the association between intraoperative burst suppression and postoperative delirium in adult surgical patients.
Methods: PubMed, MEDLINE, Embase, Google Scholar, and the Cochrane Central Register of Controlled Trials were systematically searched and updated in May 2023. We included cohort studies, case-control studies, and randomized-controlled studies reporting on postoperative delirium incidence with documented intraoperative burst suppression in adults receiving general anesthesia for any surgery. The primary outcome was the pooled odds ratio (OR) for postoperative delirium in cases with intraoperative burst suppression compared to those without burst suppression, calculated using a random-effects model. Two independent investigators extracted the data. The protocol was prospectively registered in PROSPERO (registration number: CRD42022326479); the results were reported according to PRISMA guidelines.
Results: Fourteen studies (6435 patients) were included in the analysis. The overall incidence of postoperative delirium was 21.1% (1358/6435). Patients with intraoperative burst suppression had a higher incidence of postoperative delirium than those without burst suppression (pooled OR, 1.492; 95% confidence interval (CI) [1.022-2.178]; I2 =44%; 95% CI [0%-75%]; τ2 = 0.110). The intraoperative duration of burst suppression was significantly longer in patients who developed postoperative delirium (standardized mean difference [SMD] 0.462 [95% CI, 0.293-0.632]; I2 = 63%; 95% CI [16%-84%]; τ2 = 0.027). The burst suppression ratio was significantly higher in the delirium group (SMD 0.150; 95% CI [0.055-0.245]; I2 = 0%; 95% CI [0%-85%]; τ2 = 0.00).
Conclusion: Our meta-analysis suggests an association between intraoperative burst suppression and postoperative delirium; however, the quality of evidence was very low. The limited number of studies and substantial heterogeneity across them emphasize the need for further high-quality studies to establish a more robust conclusion.
