Purpose: To compare the efficacy of intranasal dexmedetomidine and dexmedetomidine-ketamine premedication in preschool children undergoing tonsillectomy.
Patients and Methods: We enrolled 66 children with American Society of Anesthesiologists physical status I or II, aged 3– 7 years undergoing tonsillectomy. Patients were randomly allocated to receive intranasal premedication with either dexmedetomidine 2 μg kg^{− 1} (Group D) or dexmedetomidine 2 μg kg^{− 1} and ketamine 2 mg kg^{− 1} (Group DK). The primary outcome was the sedation level assessed by the Modified Observer’s Assessment of Alertness/Sedation Scale (MOAA/S) 30 min after intervention. The minimal clinically relevant difference in the MOAA/S score was 0.5. Secondary outcomes included sedation onset time, parental separation anxiety, acceptance of mask induction, emergence time, emergence delirium, postoperative pain intensity, length of stay in the post-anesthesia care unit (PACU), and adverse effects.
Results: At 30 min after premedication, the MOAA/S score was lower in Group DK than in Group D patients (median: 1.0, interquartile range [IQR]: 1.0– 2.0 vs median: 3.0, IQR: 2.0– 3.0; P< 0.001), with a median difference of 1.0 (95% confidence interval [CI]: 1.0– 2.0, P< 0.001). Patients in Group DK showed considerably faster onset of sedation (15 min, 95% CI: 14.2– 15.8 min) than Group D (24 min, 95% CI: 23.2– 24.8 min), with a median difference of 8.0 min (95% CI: 7.0– 9.0 min, P< 0.001). Both parental separation and facemask acceptance scores were lower in Group DK than in Group D patients (P=0.012 and P=0.001, respectively). There was no significant difference in emergence time, incidence of emergence delirium, postoperative pain scores, and length of stay in the PACU between the two groups.
Conclusion: Intranasal premedication with a combination of dexmedetomidine and ketamine produced better sedation for pediatric tonsillectomy than dexmedetomidine alone.

Keywords: preoperative sedation, mask induction, pediatric anesthesia


中文翻译：

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氯胺酮增强儿童鼻内右美托咪定诱导的镇静：一项随机、双盲试验。

目的：比较鼻内右美托咪定和右美托咪定-氯胺酮术前用药在学龄前儿童扁桃体切除术中的疗效。
患者和方法：我们招募了 66 名美国麻醉医师协会身体状况为 I 或 II 的儿童，年龄在 3-7 岁，接受扁桃体切除术。患者被随机分配接受右美托咪定 2 μg kg ^{- 1}（D 组）或右美托咪定 2 μg kg ^{- 1}和氯胺酮 2 mg kg ^{- 1的鼻内术前用药}（DK 组）。主要结果是干预后 30 分钟通过改良观察员警觉/镇静量表 (MOAA/S) 评估的镇静水平。MOAA/S 评分的最小临床相关差异为 0.5。次要结局包括镇静起效时间、父母分离焦虑、接受面罩诱导、苏醒时间、苏醒谵妄、术后疼痛强度、在麻醉后护理病房 (PACU) 的停留时间和不良反应。
结果：术前用药后 30 分钟，DK 组的 MOAA/S 评分低于 D 组患者（中位数：1.0，四分位距 [IQR]：1.0-2.0 vs 中位数：3.0，IQR：2.0-3.0；P < 0.001），中位数差异为 1.0（95% 置信区间 [CI]：1.0–2.0，P< 0.001)。DK 组患者的镇静起效时间（15 分钟，95% CI：14.2-15.8 分钟）明显快于 D 组（24 分钟，95% CI：23.2-24.8 分钟），中位差异为 8.0 分钟（95% CI：7.0–9.0 分钟，P < 0.001）。DK 组的父母分离和面罩接受分数均低于 D 组患者（分别为P = 0.012 和P = 0.001）。两组在苏醒时间、苏醒谵妄发生率、术后疼痛评分、PACU 停留时间等方面均无显着差异。
结论：右美托咪定和氯胺酮联合鼻内给药对小儿扁桃体切除术的镇静效果优于单独使用右美托咪定。

关键词：术前镇静、面罩诱导、小儿麻醉