Effect of intravenous lidocaine dose on pain upon awakening in pediatric tonsillectomy: A randomized trial

We investigated the potential of intravenous lidocaine to reduce pain on awakening in a dose-dependent manner and aimed to determine the median effective dose of lidocaine in 200 children aged 3–12 years (American Society of Anesthesiologists physical status I–II) who underwent elective tonsillectomy with or without adenoidectomy at Yichang Central People’s Hospital. The patients were randomized into four dose groups (A–D: 0.0, 1.0, 1.5, and 2.0 mg/kg, respectively), and they underwent the same anesthetic induction and maintenance protocols. The primary outcome was pain on awakening, while secondary outcomes included pain scores at 1, 4, 12, and 24 h after awakening; incidences of laryngospasm, bronchospasm, or perioperative stridor; and time to extubation. Intraoperative cardiac events were classified as safety events. Our findings indicated that intravenous lidocaine dose-dependently reduced pain on awakening, with the median effective dose being 1.75 mg/kg. Significant differences were observed between groups A and D (P ≤ 0.001). No incidents of laryngospasm, bronchospasm, or perioperative stridor were observed. Furthermore, there were significant between-group differences in time to extubation (P ≤ 0.05). In conclusion, our study demonstrated that lidocaine dose-dependently reduced pain on awakening in children undergoing tonsillectomy with or without adenoidectomy, with no severe adverse events.