Effect of Intravenous Etomidate versus Propofol on Seizure duration and Haemodynamic Response during Modified Electroconvulsive Therapy: A Randomised Clinical Trial

Introduction: Seizure duration in Electro convulsive Therapy (ECT) is a clinically important factor in managing psychiatric patients subjected to the procedure. Various induction agents are being used with varying efficacy on seizure duration and haemodynamic response like thiopentone, propofol, ketamine and etomidate. As repeated ECT sessions pose significant risk of general anaesthesia and its complications, in this study the efficacy of etomidate and propofol was compared.

Aim: To assess the seizure duration and compare haemodynamic variables using etomidate and propofol.

Materials and Methods: A randomised clinical trial was done in the Department of Anaesthesiology, at tertiary care hospital between July 2021 to June 2022 on 40 patients of age group 18 to 60 years of either sex, belonging to American Society of Anaesthesiologists (ASA) Grade-I and II scheduled for ECT. Patients were allocated into two groups. Preinduction baseline values of Heart Rate (HR), Systolic Blood Pressure (SBP), Diastolic Blood Pressure (DBP) and Mean Arterial Pressure (MAP) were recorded using pulse oximeter and Non Invasive Blood Pressure (NIBP). Patients were induced with either, inj. etomidate 0.2 mg/kg (Group E) or inj. propofol 1 mg/kg (Group P). HR, SBP, DBP and MAP were recorded soon after induction, after application of stimulus and at one minute interval after electric 156 shock for five minutes and then at five minutes interval. Statistical analysis was done by using the unpaired Student’s t-test for quantitative data. The p-value <0.05 was considered significant.

Results: Demographic data were similar in both the groups. The mean seizure duration in Group E (51.25±9.01 seconds) was greater than in Group P (38.30±9.92 seconds) and was statistically significant. There was significant increase in the HR in both groups and the HR did not reach the baseline even after 10 minutes. There was a rise in the mean SBP by approximately 7 mm Hg in the Group P compared to 4 mm Hg in the Group E. The mean DBP rise in the propofol group was 6 mm Hg as compared to 5 mm Hg in the Group E. The MAP in both the groups increased by 7 mm Hg. The parameters reached the baseline earlier with Group P compared to Group E.

Conclusion: The study concludes etomidate has a distinct advantage over propofol in producing seizures of adequate duration during ECT whereas propofol blunts the sympathetic response to ECT more effectively than etomidate.