不同体温管理策略对脊柱外科内固定术患者血脑屏障结构及术后认知功能障碍的影响

Effects of different temperature management strategies on blood-brain barrier and post-operative cognitive dysfunction in patients undergoing spinal fixation surgery

目的评价不同体温管理策略对脊柱外科内固定术患者血脑屏障(BBB)结构及术后认知功能障碍(POCD)的影响。方法择期静吸复合全麻下行脊柱外科内固定术患者96例,年龄44~78岁,体重45~104 kg,ASA分级Ⅰ~Ⅲ级,采用简单随机化分组法分为3组(n=32):液体加温组(WBI组)、多模式加温组(AW组)和多模式加温联合选择性脑降温组(SBC组)。WBI组患者采用医用输血输液加温器将术中静脉输注液体加热至37℃;AW组患者采用液体加温联合体表加温毯,保持加温直至手术结束,加温毯目标温度设在38℃;SBC组患者采用AW组患者相同加温方案,并联合使用设定温度为4℃的电子冰帽进行选择性脑降温。术毕时抽取患者肘正中静脉血样,采用免疫磁珠法分离鉴定脑微血管内皮细胞(BMECs),并于荧光显微镜下计数;术后第1天采用散射比浊法测定外周血C反应蛋白(CRP)浓度;分别在术前1和术后7 d时采用视觉词语学习测试、数字符号测试、连线试验和Stroop色词命名测试进行POCD发生评估。记录气管拔管时间、PACU滞留时间、总住院时间、热舒适度评分、PACU寒颤、躁动及术后发热的发生情况;术后第7天采用术后恢复质量量表(QoR-40)评估术后恢复情况。结果与WBI组比较,AW组和SBC组患者POCD发生率、PACU寒颤发生率、气管拔管时间、PACU滞留时间和血清CRP浓度降低,热舒适度评分和QoR-40评分升高(P<0.05);与AW组比较,SBC组外周血BMECs计数降低(P<0.05)。结论多模式加温不明显损伤脊柱外科内固定术患者BBB结构,可降低POCD发生;多模式加温联合选择性脑降温可改善BBB结构完整性,但未降低POCD发生。

Objective To evaluate the effects of different temperature management strategies on blood-brain barrier(BBB)and postoperative cognitive dysfunction(POCD)in the patients undergoing spinal fixation surgery.Methods Ninety-six patients,aged 44-78 yr,weighing 45-104 kg,of American Society of Anesthesiology physical statusⅠ-Ⅲ,undergoing spinal fixation surgery with combined intravenous-inhalational anesthesia,were divided into 3 groups(n=32 each)by the simple randomization:warming blood transfusion and infusion group(group WBI),active warming group(group AW)and active warming plus selective brain cooling group(group SBC).In WBI group,the fluid for intraoperative intravenous infusion was warmed to 37℃using a medical blood transfusion-infusion warmer.In AW group,warming was maintained using the fluid warming combined with the body surface warming blanket until the end of operation,and the target temperature of the warming blanket was set at 38℃.In SBC group,the warming protocol were similar to those previously described in AW group,and selective brain cooling was performed through an electronic ice cap with a set temperature of 4℃.Blood samples were collected from the median cubital vein at the end of operation,brain microvascular endothelial cells were isolated and identified by immunomagnetic bead,and the target cells were counted with a fluorescence microscope.The concentration of C-reactive protein in peripheral blood was measured by rate nephelometry on the first day after operation.The extubation time,length of post-anesthesia care unit(PACU)stay,total length of hospital stay,thermal comfortableness score,shivering in PACU,agitation and postoperative fever were recorded.The postoperative recovery was assessed using the 40-item Quality-of-Recovery scale on 7th day after surgery.Results Compared with WBI group,the incidence of POCD and shivering in PACU,extubation time,length of PACU stay,and serum C-reactive protein concentrations were significantly decreased,and thermal comfortableness score and 40-item Quality-of Recovery scale score were increased in AW group and SBC group(P<0.05).Compared with AW group,the count of brain microvascular endothelial cells was significantly decreased in SBC group(P<0.05).Conclusions Active warming produces no damage to the structure of BBB,and can reduce the development of POCD;active warming combined with selective brain cooling can improve the structural integrity of BBB,but it cannot reduce the development of POCD in the patients undergoing spinal fixation surgery.