Department of Anesthesia & Intensive Care, Post Graduate Institute of Medical Education and Research, Chandigarh, India.
J Clin Anesth. 2013 Mar;25(2):92-7. doi: 10.1016/j.jclinane.2012.06.016. Epub 2013 Jan 17.
To study the minimal effective dose of magnesium sulfate to control blood pressure (BP) during intubation in hypertensive patients.
Prospective, randomized, double-blind study.
Operating room of an academic medical center.
80 adult, ASA physical status 1 and 2, controlled hypertensive patients undergoing elective surgery under general anesthesia and requiring endotracheal intubation.
Patients were randomized to 4 groups. Patients in study groups received a magnesium sulfate infusion at a dose of 30 (Group I), 40 (Group II), or 50 mg/kg (Group III) before induction of anesthesia, while patients in control group (Group IV) received a 1.5 mg/kg lidocaine bolus 90 seconds before intubation. Anesthesia was induced and maintained with a propofol infusion. Laryngoscopy and intubation were performed 4 minutes after administration of vecuronium.
Heart rate (HR) and BP were recorded before, during, and after endotracheal intubation for 10 minutes. Measures to manage hemodynamic instability were recorded. Serum magnesium levels were also recorded.
The changes in HR were comparable among groups. Mean arterial pressure (MAP) was maintained within normal limits in Group I patients while Groups II and III patients showed a significant decrease in MAP (P = 0.01) compared with baseline. A total of 6 patients (30%) in Group II and 10 patients (50%) in Group III required interventions (P = 0.001). No patient in Group I and only one patient (5%) in Group IV required intervention.
Magnesium 30 mg/kg is the optimum dose to control BP during intubation in hypertensive patients. A further increase in the dose of magnesium may cause significant hypotension.
研究硫酸镁控制高血压患者插管期间血压（BP）的最小有效剂量。
前瞻性、随机、双盲研究。
学术医学中心的手术室。
80 名成年、ASA 身体状况 1 和 2、接受全身麻醉下择期手术且需要气管插管的控制性高血压患者。
患者随机分为 4 组。研究组患者在诱导麻醉前分别给予硫酸镁 30 毫克/公斤（I 组）、40 毫克/公斤（II 组）或 50 毫克/公斤（III 组），对照组（IV 组）患者在插管前 90 秒给予 1.5 毫克/公斤利多卡因。用丙泊酚输注诱导和维持麻醉。在给予维库溴铵后 4 分钟进行喉镜检查和插管。
在气管插管前、插管期间和插管后 10 分钟记录心率（HR）和 BP。记录处理血液动力学不稳定的措施。还记录血清镁水平。
各组间 HR 的变化相似。I 组患者的平均动脉压（MAP）维持在正常范围内，而 II 组和 III 组患者的 MAP 与基线相比显著下降（P = 0.01）。II 组有 6 名患者（30%）和 III 组有 10 名患者（50%）需要干预（P = 0.001）。I 组无患者，IV 组仅有 1 名患者（5%）需要干预。
硫酸镁 30 毫克/公斤是控制高血压患者插管期间血压的最佳剂量。镁剂量进一步增加可能导致显著低血压。
