Intravenous Lidocaine Attenuates the Pressor Response to Tracheal Intubation During Remimazolam Induction with Remifentanil Target-Controlled Infusion: A Randomized Placebo-Controlled Trial

Background and Objectives: Remimazolam provides greater hemodynamic stability during anesthetic induction than propofol; nevertheless, attenuation of the sympathetic response to tracheal intubation remains an important consideration. Remifentanil target-controlled infusion (TCI) is commonly used for this purpose, but adjunctive strategies may provide additional control of the pressor response without increasing opioid exposure. We aimed to determine whether intravenous lidocaine provides additional attenuation of the pressor response to tracheal intubation during remimazolam induction with remifentanil TCI. Materials and Methods: In this prospective, randomized, placebo-controlled trial, a total of 80 patients provided written informed consent and were randomized to the lidocaine (n = 40) or placebo (n = 40) group. Anesthesia was induced with remimazolam and remifentanil TCI. Mean arterial pressure (MAP) and heart rate (HR) were recorded at baseline, immediately before intubation, and at 1 and 2 min after tracheal intubation. The primary outcome was the change in MAP from baseline to 1 min after intubation. Clinical Research Information Service (CRIS): first posted 5 March 2026 (KCT0011685); first participant enrolled 6 March 2026. Results: Seventy-eight patients (lidocaine, n = 38; placebo, n = 40) were included in the final analysis. The primary outcome, the increase in MAP from baseline to 1 min after intubation, was significantly smaller in the lidocaine group than in the placebo group (3.97 ± 14.36 vs. 16.04 ± 16.56 mmHg; mean difference, −12.06 mmHg [95% CI, −19.07 to −5.06]; p = 0.001). Changes in HR from baseline did not differ between groups, whereas the increase in HR from immediately before to 1 min after intubation was smaller with lidocaine. Conclusions: Intravenous lidocaine attenuated the increase in MAP at the post-intubation measurement times during remimazolam induction with remifentanil TCI at a fixed target effect-site concentration of 2.0 ng/mL, although its clinical significance remains to be established.