Effect of low-dose ketamine versus lidocaine on hemodynamic response to endotracheal intubation in general anesthesia: a prospective, triple-blinded, randomized controlled trial

A smooth endotracheal intubation minimizes hemodynamic changes. We assessed the effect of ketamine and lidocaine on Diastolic blood pressure (DBP) Systolic blood pressure (SBP), heart rate (HR), Mean arterial pressure (MAP) and, oxygen saturation (SpO2) changes after endotracheal intubation compared to a control group.

In this randomized, triple-blind clinical trial (IRCT20200825048515N56) approved by the Medical Ethics Committee of the Isfahan University of Medical Sciences (IR.MUI.MED.REC.1400.721) 90 patients aged 18-65 years as candidates for surgery under general anesthesia at Alzahra Hospital in Isfahan were included between December 2022 and February 2023. They were randomly allocated to the ketamine hydrochloride (ketamine) (0.5 mg/kg), lidocaine hydrochloride 2% (Lignodic)          (0.5 mg/kg), and control groups. The subjects, age, height, weight, gender, Body mass index (BMI) and clinical information, such as mean blood pressure, HR, SBP, DBP, MAP, and, oxygen saturation 1, 3, 5 and 10 minutes following endotracheal intubation, recovery stay and, extubation time were noted and analyzed by repeated measure analysis using SPSS version 28. The significance level in all analyses was considered less than 0.05.

Ninety candidates for electroconvulsive therapy (ECT) were randomly assigned to three groups of 30: one group receiving lidocaine hydrochloride, one receiving ketamine hydrochloride, and the other a control group. Overall, 60 cases (66.7%) were male and 30 cases (33.3%) were female.
Both lidocaine and ketamine effectively reduce hemodynamic changes during endotracheal intubation, but lidocaine potentially has greater benefits in terms of improving oxygenation and reducing heart rate variability, as well as reducing recovery time during anesthesia. No significant difference was detected between the two studied groups regarding diastolic blood pressure, systolic blood pressure, heart rate, mean arterial pressure changes, recovery stay, extubation time, and laryngoscopy grade.

Based on the findings in this study, lidocaine offered more desirable hemodynamic stability than ketamine and resulted in fewer hemodynamic disturbances. Also, in the case of persistent hypertension or tachycardia. This was not observed in any of the groups.