Ketamine Enhances Intranasal Dexmedetomidine-Induced Sedation in Children: A Randomized, Double-Blind Trial

Abstract

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

Acknowledgments

We gratefully acknowledge Dr. Yong Cheng and Dr. Ruiyu Li, for their support and co-operation. This study was supported by the Medical Innovation Project of Fujian Province (grant number 2019-CXB-6), Fujian Medical University Startup Fund for scientific research (grant number 2019QH1171), and High-level hospital foster grants from Fujian Provincial Hospital (grant number 2020HSJJ01).

Data Sharing Statement

The individual participant data supporting published results, the study protocol, and the statistical analysis plan can be accessed with approval from the principal investigator (Dr. Yanhua Guo, [email protected]) after publication.

Disclosure

The authors report no conflicts of interest in this work.