Bekker Alex, Sturaitis Mary, Bloom Marc, Moric Mario, Golfinos John, Parker Erik, Babu Ramesh, Pitti Abishabeck
Department of Anesthesiology, New York University Medical Center, 560 First Ave., New York, NY 10016, USA.
Anesth Analg. 2008 Oct;107(4):1340-7. doi: 10.1213/ane.0b013e3181804298.
The perioperative course of patients undergoing intracranial surgery is frequently complicated by hypertensive episodes. Dexmedetomidine (DEX), an alpha-2 adrenoreceptor agonist, is gaining popularity in neuroanesthesia, because its sympatholytic and antinociceptive properties may improve hemodynamic stability at critical moments of surgery. We designed this study to assess the efficacy of DEX in controlling hypertensive responses in patients undergoing intracranial surgery.
Patients scheduled for elective craniotomy were randomly assigned to receive either sevoflurane-opioid or sevoflurane-opioid-DEX anesthesia. Bispectral index was used to maintain a similar level of hypnosis in both groups (40-50). Opioids, sevoflurane, and vasoactive medications were titrated in a routine manner, at the discretion of the blinded anesthesiologist managing the case, to maintain systolic blood pressure (SBP) targeted within 90-130 mm Hg and heart rate (HR) between 50 and 90 bpm. Hemodynamic variables were continuously recorded and stored on a computer for analysis. Efficacy of the anesthetic technique in controlling SBP or HR is inversely proportional to the area under the curve (AUC) outside the targeted range. Areas under the curves above and below targeted ranges for SBP-time (AUCsbp mm Hgmin/h) and HR-time (bpmmin/h) were compared. Coefficient of variation was used to assess hemodynamic stability.
Seventy-two patients were recruited for the study. Computerized records of 56 patients only were analyzed because of technical problems with data collection in 14 cases. AUCsbp for above the targeted range was significantly lower for patients in the DEX group (P=0.044). The coefficient of variation for SBP or HR did not differ between groups. A significantly smaller proportion of patients in the DEX group required treatment with antihypertensive medications (12 of 28, 42% vs 24 of 28, 86%, P=0.0008). The DEX group required fewer opioids in the intraoperative period, but there were no differences in the use of sevoflurane. In the postanesthesia care unit, patients in the DEX group had fewer hypertensive episodes (1.25+/-1.55 vs 2.50+/-2.00, P=0.0114) and were discharged earlier (91+/-17 vs 130+/-27 min, P<0.0001). There were no differences in the requirement for postoperative opioids or antiemetics.
By using indices, which assess a global hemodynamic stability of the anesthetic, we determined that intraoperative DEX infusion was effective for blunting the increases in SBP perioperatively. The use of DEX did not increase the incidence of hypotension or bradycardia, common side effects of the drug.
接受颅内手术的患者围手术期经常并发高血压发作。右美托咪定（DEX）是一种α-2肾上腺素能受体激动剂，在神经麻醉中越来越受欢迎，因为其抗交感神经和镇痛特性可能在手术关键时刻改善血流动力学稳定性。我们设计本研究以评估DEX在控制颅内手术患者高血压反应中的疗效。
计划接受择期开颅手术的患者被随机分配接受七氟醚-阿片类药物或七氟醚-阿片类药物-DEX麻醉。使用脑电双频指数使两组维持相似的催眠水平（40-50）。阿片类药物、七氟醚和血管活性药物由负责该病例的不知情麻醉医生酌情按常规方式滴定，以维持收缩压（SBP）目标在90-130mmHg之间，心率（HR）在50-90bpm之间。血流动力学变量持续记录并存储在计算机上以供分析。麻醉技术控制SBP或HR的疗效与目标范围外的曲线下面积（AUC）成反比。比较SBP-时间（AUCsbp mmHgmin/h）和HR-时间（bpmmin/h）目标范围上下的曲线下面积。变异系数用于评估血流动力学稳定性。
72例患者被纳入研究。因14例数据收集存在技术问题，仅分析了56例患者的计算机记录。DEX组患者目标范围以上的AUCsbp显著更低（P=0.044）。两组间SBP或HR的变异系数无差异。DEX组需要使用抗高血压药物治疗的患者比例显著更小（28例中的12例，42%对28例中的24例，86%，P=0.0008）。DEX组术中期需要的阿片类药物更少，但七氟醚的使用无差异。在麻醉后护理单元，DEX组患者高血压发作更少（1.25±1.55对2.50±2.00，P=0.0114）且出院更早（91±17对130±27分钟，P<0.0001）。术后阿片类药物或止吐药的需求无差异。
通过使用评估麻醉整体血流动力学稳定性的指标，我们确定术中输注DEX对减轻围手术期SBP升高有效。DEX的使用未增加该药物常见副作用低血压或心动过缓的发生率。
