小剂量麻醉药物用于神经外科患者早期苏醒的随机前瞻性研究

背景开颅术后为尽早观察神经系统的并发症，使患者从麻醉状态中迅速苏醒至关重要。然而快通道技术常常会伴有体循环高血压，后者有潜在诱发颅内血肿的风险。尽管到目前为止巳研究了很多种药物，但用麻醉药物缓解苏醒期高血压的研究不多。本研究拟观察在关颅阶段应用小剂量麻醉药物能否有助于患者早期苏醒并减轻血流动力学反应。方法在150例血压正常行小脑幕上肿瘤切除术患者中，评价3种苏醒方法的效果，这些患者均采用异氟烷标准麻醉。患者随机分为3组，关闭硬脑膜时分别给予小剂量丙泊酚（3mg·kg^-1·h^-1），芬太尼（1．5μg·kg^-1·h^-1），异氟烷（呼气末浓度为0．2％）直至开始缝皮。头部包扎结束时停止使用氧化亚氮。结果中位苏醒时间丙泊酚组为6分钟，芬太尼组为4分钟，异氟烷组为5分钟（P=0．008）。与拔管时和拔管后相比，患者拔管前更容易出现高血压（P=0．009）。3组间比较，芬太尼组拔管前和总体艾司洛尔使用率较低（P=0．01）。手术前脑显像显示严重的大脑中线偏移是苏醒期高血压的独立危险因素。结论关颅时的疼痛可能是交感刺激引起苏醒期高血压的重要原因。关颅时给予小剂量芬太尼比丙泊酚、异氟烷对神经外科患者早期苏醒更具有优势，而且是预防手术后早期高血压最有效的方法。

BACKGROUND： For early detection of a cerebral complication, rapid awakening from anesthesia is essential after craniotomy. Systemic hypertension is a major drawback associated with fast tracking, which may predispose to formation of intracranial hematoma. Although various drugs have been widely evaluated, there are limited data with regards to use of anesthetics to blunt emergence hypertension. We hypothesized that use of lowdose anesthetics during craniotomy closure facilitates early emergence with a decrease in hemodynamic consequences. METHODS： Three emergent techniques were evaluated in 150 normotensive adult patients operated for supratentorial tumors under standard isoflurane anesthesia. At the time of dural closure, the patients were randomized to receive low-dose propofol （3 mg·kg^-1·h^-1）, fentanyl （1.5 mg·kg^-1·h^-1） or isoflurane （end-tidal concentration of 0. 2%） until the beginning of skin closure. Nitrous oxide was discontinued after head dressing. RESULTS： Median time to emergence was 6 min with propofol, 4 min with fentanyl, and 5 rain with isoflurane （P = 0. 008）. More patients had hypertension in the pre-extubation compared with extubation or postextubation phase （P = 0. 009）. Comparing the three groups, fewer patients required esmolol with fentanyl use overall, and in the preextubation phase （P = 0. 01）. Significant midline shift in the preoperative cerebral imaging scans was found to be an independent risk factor for emergence hypertension. CONCLUSIONS： Pain during surgical closure may be an important cause of sympathetic stimulation leading to emergence hypertension. The use of low-doses of fentanyl during craniotomy closure is more advantageous than propofol or isoflurane for early emergence in neurosurgical patients and is the most effective technique for preventing early postoperative hypertension.