Department of Anesthesiology, Duke University Medical Center, Durham Veterans Administration Medical Center, Durham, North Carolina, USA.
Curr Opin Crit Care. 2011 Aug;17(4):376-81. doi: 10.1097/MCC.0b013e328348bece.
The elderly are the fastest growing segment of the population and undergo 25-30% of all surgical procedures. Postoperative cognitive problems are common in older patients following major surgery. The socioeconomic implications of these cognitive disorders are profound; cognitive decline is associated with a loss of independence, a reduction in the quality of life, and death. This review will focus on the two most common cognitive problems following surgery: postoperative delirium and postoperative cognitive dysfunction (POCD).
For years, preoperative geriatric consultation/screening was the only intervention proven to decrease postoperative delirium. There are, however, several recent publications indicating that preoperative and postoperative pharmacological and medical (hydration, oxygenation) management can reduce postoperative delirium. Spinal anesthesia with minimal propofol sedation has been shown to decrease the incidence of postoperative delirium in hip-fracture patients. Likewise, dexmedetomidine sedation in mechanically ventilated patients in the ICU is associated with less postoperative delirium and shorter ventilator times. Preoperative levels of education and brain function (cognitive reserve) may predict patients at risk for postoperative cognitive problems. Reduced white matter integrity is reported to place patients at a higher risk for both postoperative delirium and POCD.
The etiology of postoperative cognitive problems is unknown, but there is emerging evidence that decreased preoperative cognitive function contributes to the development of postoperative delirium and POCD. There is growing concern that inhalation anesthetics may be neurotoxic to the aging brain, but there are no human data evaluating this hypothesis to date. Randomized controlled trials evaluating interventions to improve long-term cognitive outcomes in elderly patients are urgently needed.
老年人是人口增长最快的群体，占所有手术的 25-30%。老年人在接受大手术后常出现术后认知问题。这些认知障碍的社会经济影响是深远的；认知能力下降与独立性丧失、生活质量下降和死亡有关。本综述将重点讨论手术后最常见的两种认知问题：术后谵妄和术后认知功能障碍（POCD）。
多年来，术前老年科咨询/筛查是唯一被证明可降低术后谵妄发生率的干预措施。然而，有几项最新研究表明，术前和术后的药理学和医学（补液、氧合）管理可以降低术后谵妄的发生率。最小剂量丙泊酚镇静的椎管内麻醉已被证明可降低髋部骨折患者术后谵妄的发生率。同样，在 ICU 接受机械通气的患者中使用右美托咪定镇静与术后谵妄发生率降低和通气时间缩短有关。术前的教育水平和大脑功能（认知储备）可能预测术后认知问题的高危患者。据报道，白质完整性降低会使患者面临更高的术后谵妄和 POCD 风险。
术后认知问题的病因尚不清楚，但有越来越多的证据表明，术前认知功能下降会导致术后谵妄和 POCD 的发生。人们越来越担心吸入麻醉剂可能对衰老的大脑具有神经毒性，但目前尚无评估这一假说的人体数据。迫切需要进行随机对照试验，以评估改善老年患者长期认知结局的干预措施。
