A Loading Dose of Dexmedetomidine With Constant Infusion Inhibits Intraoperative Neuromonitoring During Thoracic...

Area of Science:

• Anesthesiology
• Neurosurgery
• Neurophysiology

Background:

• Intraoperative neuromonitoring (IONM) is crucial for spinal surgeries.
• The impact of dexmedetomidine on IONM during these procedures is debated.
• Varied reports exist regarding dexmedetomidine's effect on IONM parameters.

Purpose of the Study:

• To evaluate the effect of a dexmedetomidine bolus dose on IONM during thoracic spinal decompression surgery (TSDS).
• To compare IONM parameters under different dexmedetomidine administration protocols.
• To determine the optimal use of dexmedetomidine during TSDS with IONM.

Main Methods:

• A randomized, double-blinded, placebo-controlled study involving 165 patients undergoing TSDS.
• Three groups: TIVA alone (T), TIVA with continuous dexmedetomidine infusion (D1), and TIVA with dexmedetomidine loading dose plus infusion (D2).
• IONM parameters were recorded and compared against baseline values and between groups.

Main Results:

• The dexmedetomidine loading dose group (D2) showed significant suppression of IONM parameters compared to baseline.
• Group D2 exhibited decreased SSEP and MEP amplitudes and increased SSEP latency.
• No significant IONM changes were observed between the TIVA-only group (T) and the continuous infusion group (D1).

Conclusions:

• A loading dose of dexmedetomidine significantly inhibits IONM parameters during TSDS.
• The timing of dexmedetomidine bolus administration requires careful consideration when IONM is used.
• Continuous infusion of dexmedetomidine at a specified rate does not negatively impact IONM data.