Intravenous lidocaine reduces cough but not propofol dose during gastroscopy: a prospective, randomised controlled double-blind study

Abstract

Background: To improve patient comfort during gastroscopy, sedation is essential. Propofol can cause adverse effects if underdosed or overdosed. Lidocaine has been suggested as an adjuvant to propofol in this context.

Objectives: This study aimed to evaluate propofol consumption when adding intravenous lidocaine during gastroscopy. We also assessed whether intravenous lidocaine reduces the adverse effects associated with inappropriate sedation.

Design: Prospective, randomised, controlled, double-blind, single-centre trial.

Setting: Day hospital of the Erasme University Hospital, from 21 July to 25 August 2023.

Methods: American Society of Anaesthesiologists’ physical status 1 or 2 patients, aged < 65 years and undergoing gastroscopy procedure were included. Patients were randomly assigned to receive either 1.5 mg/kg Lidocaine (Lidocaine-group) or placebo (Control-group). Sedation was achieved by the administration of propofol using target-concentration infusion titrated according to the bispectral index.

Main Outcome Measures: Primary outcome was propofol consumption between groups. Secondary endpoints included the occurrence of cough, involuntary movements, hypoxaemia, hypotension, tinnitus and metallic taste, as well as the satisfaction of the gastroenterologist.

Results: Lidocaine did not reduce propofol consumption but did reduce coughing on gastroscope insertion (9%) compared to placebo (52%) (p=0.002). Rates of involuntary movement, hypotension, desaturation as well as gastroenterologist satisfaction were similar. Only patients who received lidocaine experienced tinnitus (52%; p < 0.001) and metallic taste (28%; p = 0.004).

Conclusion: The administration of intravenous lidocaine did not reduce the consumption of propofol, but it did significantly reduce coughing during the insertion of a gastroscope, however without having any clinical effect. A high rate of mild local anaesthetic side effects was associated with lidocaine administration.

Trial Registration: Clinicaltrials.gov identifier: NCT05944887