不同剂量右美托咪定对小儿MRI下脑立体定向术麻醉效果比较

 目的 比较几种维持剂量右美托咪定应用于小儿MRI下脑立体定向术中的麻醉效果。方法 90例术前需行MRI下脑立体定向检查且完全不能自主配合的患儿,随机分为3组:D₁组、D₂组和D₃组,每组30例。入室后所有患儿先给予丙泊酚1～3 mg/kg使其充分镇静。3组右美托咪定负荷剂量均为1.0 μg/㎏,10 min泵完,维持剂量:D₁组为0.5 μg/(kg·h),D₂组为0.7μg/(kg·h),D₃组为1.0 μg/(kg·h)。患儿给丙泊酚并入睡后在局麻下安放立体定向仪头架,入磁共振室前停用右美托咪定。记录3组患儿入手术室(T₀)、上头架前(T₁)、上头架即刻(T₂)、上头架完成后(T₃)、入磁共振室之前(T₄)、出磁共振室之后(T₅)NBP、HR、RR和SPO₂的变化,并记录各组患儿丙泊酚用量、需追加丙泊酚的病例数,以及呼吸抑制、过早苏醒、术后躁动等不良反应的发生情况。结果 与D₁组比较,D₂组和D₃组丙泊酚用量明显减少(P<0.01);D₁组需单次追加丙泊酚的例数为17例,呼吸抑制病例数为10例,其中1例因严重呼吸抑制而放弃检查;D₂组需单次追加丙泊酚的例数为5例,明显少于D₁组(P<0.01),无呼吸抑制发生(P<0.05);D₃组所有患儿检查过程中均不需追加丙泊酚,且无呼吸抑制(P<0.05),HR有所下降,但仍在正常范围;3组术后苏醒情况无明显差异。结论 在小儿MRI下脑立体定向过程中,右美托咪定以1.0 μg/kg负荷,并以1.0 μg/(kg·h)维持较好,它既可以明显减少追加丙泊酚的次数及剂量,还可保证患儿在检查全程安静不动,且无呼吸抑制。

A comparison of different doses of dexmedetomidine in pediatric patients undergoing stereotaxic procedure by MRI

Objective To evaluate the efficacy and safety of administration of different doses of dexmedetomidine in pediatric patients who need a preoperative stereotaxic procedure by magnetic resonance imaging (MRI). Methods 90 pediatric patients who needed stereotaxic check by MRI under basic anesthesia were randomly divided into three groups, D₁, D₂ and D₃, 30 subjects per group. All subjects were given propofol 1-3 mg/kg to get thorough sedation. The loading dose of dexmedetomidine was 1 μ k/ kg, the maintenance dose in D₁ group was 0.5 μg/(kg·h), D₂ group was 0.7 μg/(kg·h), and D₃ group was 1.0 μg/(kg·h). After they fell asleep, all subjects were given local anesthesia to put on the stereotaxic instrument. Patients’ NBP, HR, RR and SPO₂ were recorded at several necessary time points, the dosage of propofol, the cases who needed additional propofol were recorded as well. Additionally, we also observed the incidence of adverse events such as respiratory depression, unexpected early recovery and postoperative agitation. Results Compared with D₁ group ,the dosage of propofol were significantly reduced in D₂ group and D₃ group( P<0.01 ). In D₁ group, there were 17 subjects who needed additional propofol, 10 subjects had respiratory depression, and among them one patient had to give up the examination because of severe respiratory depression .There were only 5 cases in D₂ group who needed additional propofol, obviously less than in D₁ group(P<0.01); no respiratory depression occurred in D₂ group(P<0.05 ).All the children in D₃ group finished stereotaxic check without additional propofol, no respiratory depression occurred as well (P<0.05 ). In addition, the heart rate in D₃ group dropped somewhat during the checking time, but still within the normal range. There was no significant difference in postoperative recovery status among these three groups. Conclusions During stereotaxic checking period by MRI in pediatric patients, the maintenance dose1.0 μg/(kg·h) of dexmedetomidine after a loading dose of 1.0 μg/kg can not only reduce the additional injection of propofol, but also ensure the children’s quietness and security without respiratory depression.