七氟醚麻醉下控制性降压对脊柱手术术后认知功能障碍的影响

目的探讨七氟醚麻醉下控制性降压对脊柱手术术后认知功能障碍（postoperative cognitive dysfunction,POCD）及血清S-100β浓度的影响。方法选择ASAⅠ～Ⅲ级,45至65岁择期行单节段腰椎切开复位内固定手术患者45例,随机均分为硝酸甘油控制性降压组（A组,n=22例）与对照组（C组,n=23例）。常规诱导麻醉后,两组患者均吸入七氟醚维持BIS值在45至55,间断给予维库溴铵,芬太尼维持麻醉。A组术中静脉微泵输注硝酸甘油进行控制性降压,使平均动脉压下降幅度维持在麻醉前30%左右,并维持MAP≥50mmHg,C组静脉输注等容量生理盐水。分别于术前1d、术后1d、3d、5d采用简化智能评分（Mini-metal state examination,MMSE）评估认知功能,术后MMSE值较术前降低2分则诊断为POCD。在相应时点抽取静脉血,采用免疫酶联吸附法（ELISA）测定血清S-100β浓度。结果两组患者术前MMSE评分,S-100β蛋白测定值比较无差异。术后1d、3d A组POCD发生率显著低于C组（P〈0.05,P〈0.01）;术后5d POCD发生率两组无显著差异（P〉0.05）。术后各时间点两组患者血清S-100β浓度均较术前升高（P〈0.05,P〈0.01）。术后1,3d A组较C组血清S-100β差异有统计学意义（P〈0.05）,术后第五天两组无显著差异。结论术中控制性降压可提高脊柱手术患者术后早期POCD发病率及血清S-100β浓度。

Effect of controlled hypotension on early postoperative cognitive dysfunction under Sevoflurane anesthesia in splnal surgery

OBJECTIVE To investigated the effects of controlled hypotension on early postoperative cognitive function and serum protein S-100β under sevoflurane anesthesia in spinal surgery.METHODS Forty five patients aged 45～65 years,scheduled for single spinal surgery with ASAⅠ～Ⅲ,which were randomly divided into controlled hypotension group(group A,n=22)and normal blood pressure group(group C,n=23),all patients received general anesthesia with tracheal intubation and inhaled sevoflurane maintained anesthesia.In group A controlled hypotension was induced and maintained by continuous iv infusion of NTG decreased by about 30% with the lowest limited above 50 mmHg.Mini-metal state examination(MMSE)and serum S-100β were assessed at preoperative 1d,postoperative 1d,3d,5d,respectively.POCD was diagnosised when MMSE score declined 2 compared with baseline.RESULTS Among the patients studied,there was no significant difference between two groups before surgery.At 1d after surgery,POCD incidences were 12(63.6%)in A group,4(17.4%)in C group(P<0.01).At 3d after surgery,POCD was present 5(22.7%)in A group,2(8.7%)in C group(P<0.05).At 5d after surgery,the prevalence of cognitive dysfunction were similar but serum S-100β were significantly higher in group A compared to group C subjects(P<0.05).CONCLUSION Controlled hypotension when applied to single spinal surgery should increased incidence of POCD and serum S-100β.