Institute of Anaesthesiology, University of Zurich and University Hospital of Zurich, Zurich, Switzerland.
Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Zurich, Switzerland.
Acta Anaesthesiol Scand. 2018 Oct;62(9):1182-1193. doi: 10.1111/aas.13168. Epub 2018 Jun 26.
Postoperative cognitive complications are associated with substantial morbidity and mortality. Ketamine has been suggested to have neuroprotective effects in various settings. This systematic review evaluates the effects of intraoperative ketamine administration on postoperative delirium and postoperative cognitive dysfunction (POCD).
Medline, Embase and Central were searched to 4 March 2018 without date or language restrictions. We considered randomised controlled trials (RCTs) comparing intraoperative ketamine administration versus no intervention in adults undergoing surgery under general anaesthesia. Primary outcomes were postoperative delirium and POCD. Non-cognitive adverse events, mortality and length of stay were considered as secondary outcomes. Data were independently extracted. The quality of the evidence (GRADE approach) was assessed following recommendations from the Cochrane collaboration. Risk ratios were calculated for binary outcomes, mean differences for continuous outcomes. We planned to explore the effects of age, specific anaesthesia regimen, depth of anaesthesia and intraoperative haemodynamic events through subgroup analyses.
Six RCTs were included. The incidence of postoperative delirium did not differ between groups (4 trials, 557 patients, RR 0.83, 95% CI [0.25, 2.80]), but patients receiving ketamine seemed at lower risk of POCD (3 trials, 163 patients, RR 0.34, 95% CI [0.15, 0.73]). However, both analyses presented limitations. Therefore, the quality of the evidence (GRADE) was deemed low (postoperative delirium) and very low (POCD).
The effect of ketamine on postoperative delirium remains unclear but its administration may offer some protection towards POCD. Large, well-designed randomised trials are urgently needed to further clarify the efficacy of ketamine on neurocognitive outcomes.
术后认知并发症与大量发病率和死亡率相关。氯胺酮在各种情况下均具有神经保护作用。本系统评价评估了术中给予氯胺酮对术后谵妄和术后认知功能障碍（POCD）的影响。
截至 2018 年 3 月 4 日，无日期或语言限制，我们对 Medline、Embase 和中央进行了检索。我们考虑了比较全身麻醉下手术的成年人术中给予氯胺酮与无干预的随机对照试验（RCT）。主要结局是术后谵妄和 POCD。非认知不良事件、死亡率和住院时间被认为是次要结局。数据由独立人员提取。根据 Cochrane 协作组的建议，评估证据质量（GRADE 方法）。对于二项结局，计算风险比，对于连续结局，计算均数差异。我们计划通过亚组分析探索年龄、特定麻醉方案、麻醉深度和术中血流动力学事件的影响。
纳入了 6 项 RCT。两组术后谵妄发生率无差异（4 项试验，557 例患者，RR 0.83，95%CI [0.25, 2.80]），但接受氯胺酮的患者 POCD 风险似乎较低（3 项试验，163 例患者，RR 0.34，95%CI [0.15, 0.73]）。然而，这两项分析均存在局限性。因此，证据质量（GRADE）被认为是低（术后谵妄）和极低（POCD）。
氯胺酮对术后谵妄的影响仍不清楚，但给予氯胺酮可能对 POCD 有一定的保护作用。迫切需要进行大型、精心设计的随机试验，以进一步阐明氯胺酮对神经认知结局的疗效。
