Mathew Joseph P, Mackensen G Burkhard, Phillips-Bute Barbara, Stafford-Smith Mark, Podgoreanu Mihai V, Grocott Hilary P, Hill Steven E, Smith Peter K, Blumenthal James A, Reves J G, Newman Mark F
Department of Anesthesiology, Duke University Medical Center, Durham, North Carolina 27710, USA.
Anesthesiology. 2007 Oct;107(4):577-84. doi: 10.1097/01.anes.0000281896.07256.71.
Strategies for neuroprotection including hypothermia and hemodilution have been routinely practiced since the inception of cardiopulmonary bypass. Yet postoperative neurocognitive deficits that diminish the quality of life of cardiac surgery patients are frequent. Because there is uncertainty regarding the impact of hemodilution on perioperative organ function, the authors hypothesized that extreme hemodilution during cardiac surgery would increase the frequency and severity of postoperative neurocognitive deficits.
Patients undergoing coronary artery bypass grafting surgery were randomly assigned to either moderate hemodilution (hematocrit on cardiopulmonary bypass >or=27%) or profound hemodilution (hematocrit on cardiopulmonary bypass of 15-18%). Cognitive function was measured preoperatively and 6 weeks postoperatively. The effect of hemodilution on postoperative cognition was tested using multivariable modeling accounting for age, years of education, and baseline levels of cognition.
After randomization of 108 patients, the trial was terminated by the Data Safety and Monitoring Board due to the significant occurrence of adverse events, which primarily involved pulmonary complications in the moderate hemodilution group. Multivariable analysis revealed an interaction between hemodilution and age wherein older patients in the profound hemodilution group experienced greater neurocognitive decline (P = 0.03).
In this prospective, randomized study of hemodilution during cardiac surgery with cardiopulmonary bypass in adults, the authors report an early termination of the study because of an increase in adverse events. They also observed greater neurocognitive impairment among older patients receiving extreme hemodilution.
自体外循环开始以来，包括低温和血液稀释在内的神经保护策略一直被常规应用。然而，心脏手术患者术后神经认知功能障碍频繁出现，这降低了他们的生活质量。由于血液稀释对围手术期器官功能的影响尚不确定，作者推测心脏手术期间的极度血液稀释会增加术后神经认知功能障碍的发生率和严重程度。
接受冠状动脉搭桥手术的患者被随机分为中度血液稀释组（体外循环时血细胞比容≥27%）或深度血液稀释组（体外循环时血细胞比容为15 - 18%）。术前及术后6周测量认知功能。采用多变量模型对年龄、受教育年限和认知基线水平进行分析，以测试血液稀释对术后认知的影响。
在108例患者随机分组后，由于不良事件的大量发生，该试验被数据安全监测委员会终止，这些不良事件主要发生在中度血液稀释组，涉及肺部并发症。多变量分析显示血液稀释与年龄之间存在交互作用，其中深度血液稀释组的老年患者神经认知功能下降更明显（P = 0.03）。
在这项针对成人体外循环心脏手术期间血液稀释的前瞻性随机研究中，作者报告由于不良事件增加，该研究提前终止。他们还观察到接受极度血液稀释的老年患者神经认知功能损害更严重。
