A Loading Dose of Dexmedetomidine With Constant Infusion Inhibits Intraoperative Neuromonitoring During Thoracic Spinal Decompression Surgery: A Randomized Prospective Study

Tun Liu; Yue Qin; Huaguang Qi; Zhenguo Luo; Liang Yan; Pengfei Yu; Buhuai Dong; Songchuan Zhao; Xucai Wu; Zhen Chang; Zhian Liu; Xuemei Liu; Tao Yuan; Houkun Li; Li Xiao; Gang Wang

doi:10.3389/fphar.2022.840320

A Loading Dose of Dexmedetomidine With Constant Infusion Inhibits Intraoperative Neuromonitoring During Thoracic Spinal Decompression Surgery: A Randomized Prospective Study

Front Pharmacol. 2022 Mar 7:13:840320. doi: 10.3389/fphar.2022.840320. eCollection 2022.

Authors

Tun Liu¹, Yue Qin¹, Huaguang Qi², Zhenguo Luo¹, Liang Yan³, Pengfei Yu⁴, Buhuai Dong¹, Songchuan Zhao³, Xucai Wu¹, Zhen Chang³, Zhian Liu⁵, Xuemei Liu², Tao Yuan², Houkun Li³, Li Xiao¹, Gang Wang⁵

Affiliations

¹ Department of Anesthesiology, Xi'an Honghui Hospital, Xi'an Jiaotong University Health Science Center, Xi'an, China.
² Department of Functional Inspection Section, Xi'an Honghui Hospital, Xi'an Jiaotong University Health Science Center, Xi'an, China.
³ Department of Spine Surgery, Xi'an Honghui Hospital, Xi'an Jiaotong University Health Science Center, Xi'an, China.
⁴ Department of Gastrointestinal Surgery, Xijing Hospital of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
⁵ The Key Laboratory of Biomedical Information Engineering, Ministry of Education, School of Life Science and Technology, Institute of Biomedical Engineering, Xi'an Jiaotong University, Xi'an, China.

Abstract

Background: The effect of a bolus dose of dexmedetomidine on intraoperative neuromonitoring (IONM) parameters during spinal surgeries has been variably reported and remains a debated topic. Methods: A randomized, double-blinded, placebo-controlled study was performed to assess the effect of dexmedetomidine (1 μg/kg in 10 min) followed by a constant infusion rate on IONM during thoracic spinal decompression surgery (TSDS). A total of 165 patients were enrolled and randomized into three groups. One group received propofol- and remifentanil-based total intravenous anesthesia (TIVA) (T group), one group received TIVA combined with dexmedetomidine at a constant infusion rate (0.5 μg kg^-1 h^-1) (D₁ group), and one group received TIVA combined with dexmedetomidine delivered in a loading dose (1 μg kg^-1 in 10 min) followed by a constant infusion rate (0.5 μg kg^-1 h^-1) (D₂ group). The IONM data recorded before test drug administration was defined as the baseline value. We aimed at comparing the parameters of IONM. Results: In the D₂ group, within-group analysis showed suppressive effects on IONM parameters compared with baseline value after a bolus dose of dexmedetomidine. Furthermore, the D₂ group also showed inhibitory effects on IONM recordings compared with both the D₁ group and the T group, including a statistically significant decrease in SSEP amplitude and MEP amplitude, and an increase in SSEP latency. No significance was found in IONM parameters between the T group and the D₁ group. Conclusion: Dexmedetomidine delivered in a loading dose can significantly inhibit IONM parameters in TSDS. Special attention should be paid to the timing of a bolus dose of dexmedetomidine under IONM. However, dexmedetomidine delivered at a constant speed does not exert inhibitory effects on IONM data.

Keywords: dexmedetomidine; intraoperative neuromonitoring; motor evoked potential (MEP); somatosensory evoked potential (SSEP); thoracic spinal decompression surgery.