Etomidate vs. Thiopentone in Electroconvulsive Therapy

The choice of anesthetic for electroconvulsive therapy is based on the anesthetic requirements to be met and on the agent‘s impact on the seizure threshold. Thus, the non-barbiturate anesthesia etomidate revealed properties to enhance the seizure duration. Even though precisely this feature makes etomidate so valuable, little research has been done on the use of etomidate in ECT. The aim of the present study was to compare the barbiturate anesthesia thiopentone with etomidate, with the focus of attention being the quality of seizure. In 13 patients, the paradigm of a single intra-individual crossover anesthesia during maintenance ECT was selected. The excitatory effects and the electroencephalographic changes were described. Furthermore, significant differences in motor seizure duration (26.69 sec ± 9.7 vs. 35.92 sec ± 9.2; p < 0.007) and EEG seizure duration (39 sec ± 14.1 sec vs. 61 sec ± 22.2 sec; p < 0.0009) were observed. Our results confirm previous findings and reveal that after etomidate the quality of seizure can be improved not only in terms of duration. The growing knowledge of the mode of action of anesthetics/hypnotics from an anesthesiological point of view and the better understanding of subcortical and cortical mechanisms, with particular consideration of the motor seizure threshold, facilitate a differentiated choice of the narcotic and the optimization of short anesthesia in the course of electroconvulsive therapy.

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