Rokhtabnak Faranak, Djalali Motlagh Soudabeh, Ghodraty Mohamadreza, Pournajafian Alireza, Maleki Delarestaghi Mojtaba, Tehrani Banihashemi Arash, Araghi Zeinab
Department of Anesthesia, Iran University of Medical Sciences, Tehran, Iran.
Department of Otolaryngology, Iran University of Medical Sciences, Tehran, Iran.
Anesth Pain Med. 2017 Dec 26;7(6):e64032. doi: 10.5812/aapm.64032. eCollection 2017 Dec.
The current study aimed at comparing the efficacy of dexmedetomidine and magnesium sulfate to control blood pressure (BP) during rhinoplasty and the resultant effects on the quality of surgical field in terms of bleeding and visibility.
The current randomized, prospective, double-blind study was conducted on 60 patients aged 18 to 50 years classified as ASA (American Society of Anesthesiologists) physical status I who were candidates for rhinoplasty. Patients were randomly divided into 2 groups: (1) group Dex, received 1 µg/kg dexmedetomidine in 10 minutes before induction of anesthesia, followed by 0.4 - 0.6 µg/kg/hour during the maintenance of anesthesia, and (2) group Mg, received 40 mg/kg in 10 minutes before anesthesia induction followed by 10 - 15 mg/kg/hour during anesthesia maintenance. In both groups, the goal was to achieve a mean arterial pressure (MAP) of 60 - 70 mmHg. Hemodynamic variables, anesthetic, opioid, muscle relaxant requirements, and surgical field condition were recorded. Sedation score, time to reach modified Aldrete score ≥ 9, and adverse effects including nausea and vomiting (N&V) and shivering were recorded.
Controlled hypotension was achieved in both groups. There was no significant difference in MAP between the groups, but heart rate (HR) was significantly lower in the Dex group (P < 0.001), compared with that of the Mg group. Bleeding score was lower (P < 0.001) and surgeon's satisfaction score was higher (P < 0.001) in the Dex group. More patients required fentanyl (P < 0.001) or nitroglycerin (P < 0.001) and the mean fentanyl (P = 0.005) or nitroglycerin (P < 0.001) required doses were higher in the Mg group. Patients in the Dex group required more frequent administration of cisatracurium (P = 0.004). Five patients in the Dex group versus no patients in the Mg group received atropine (P = 0.023). Ramsay sedation score and time to reach modified Aldrete score ≥ 9 were significantly higher in the Dex group (P < 0.001 and P < 0.001, respectively). The incidence rate of N&V and shivering were similar in both groups.
Dexmedetomidine was more effective than magnesium to achieve controlled hypotension, and provide a favorable surgical field condition. However, dexmedetomidine also heightened the risk of induced bradycardia and prolonged sedation. These are 2 important points to consider when applying this drug as a hypotensive agent during operation.
本研究旨在比较右美托咪定和硫酸镁在鼻整形术中控制血压（BP）的疗效，以及它们对手术视野出血和可视性方面的影响。
本项随机、前瞻性、双盲研究纳入了60例年龄在18至50岁、美国麻醉医师协会（ASA）身体状况分级为I级的鼻整形术候选患者。患者被随机分为两组：（1）右美托咪定组（Dex组），在麻醉诱导前10分钟静脉注射1μg/kg右美托咪定，麻醉维持期间以0.4 - 0.6μg/kg/小时的速度持续输注；（2）硫酸镁组（Mg组），在麻醉诱导前10分钟静脉注射40mg/kg硫酸镁，麻醉维持期间以10 - 15mg/kg/小时的速度持续输注。两组的目标均是使平均动脉压（MAP）维持在60 - 70mmHg。记录血流动力学变量、麻醉药、阿片类药物、肌肉松弛剂的用量以及手术视野情况。记录镇静评分、达到改良Aldrete评分≥9分的时间，以及恶心呕吐（N&V）和寒战等不良反应。
两组均成功实现控制性低血压。两组间MAP无显著差异，但右美托咪定组的心率（HR）显著低于硫酸镁组（P < 0.001）。右美托咪定组的出血评分更低（P < 0.001），外科医生的满意度评分更高（P < 0.001）。硫酸镁组更多患者需要使用芬太尼（P < 0.001）或硝酸甘油（P < 0.001），且硫酸镁组所需芬太尼（P = 0.005）或硝酸甘油（P < 0.001）的平均剂量更高。右美托咪定组患者需要更频繁地使用顺式阿曲库铵（P = 0.004）。右美托咪定组有5例患者使用了阿托品，而硫酸镁组无患者使用（P = 0.023）。右美托咪定组的Ramsay镇静评分和达到改良Aldrete评分≥9分的时间显著更高（分别为P < 0.001和P < 0.001）。两组N&V和寒战的发生率相似。
在实现控制性低血压和提供良好手术视野条件方面，右美托咪定比硫酸镁更有效。然而，右美托咪定也增加了诱发心动过缓和延长镇静时间的风险。在手术中使用该药物作为降压药时，这是两个需要考虑的重要因素。
