Electroconvulsive therapy (ECT) is a well-established treatment for severe depression and remains the most effective option when rapid symptom relief is required, such as in acutely suicidal patients. This thesis aims to examine variations in ECT anaesthesia practices across Finnish neuromodulation units and to explore their potential consequences for the treatment of severely depressed patients.

The thesis comprises three substudies. The first two are based on a survey conducted in Finnish neuromodulation units, which included 72 questions covering staff qualifications, the selection of anaesthetic agents and adjuvants, patient monitoring methods, and reported adverse effects (AEs). The first substudy focused on differences in anaesthesia practices, while the second explored the reported AEs, their perceived frequency, and the medications used to manage them.

The first substudy revealed considerable variation, particularly in the anaesthetists’ educational backgrounds, the choice of general anaesthetics, and the management of AEs. Propofol and methohexital were the most commonly used anaesthetic agents. The second substudy found headache to be the most frequently reported AE, followed by confusion, hypertension, muscle pain, and nausea. Notably, the recognition and pharmacological treatment of AEs differed between units, raising concerns that some may go unnoticed or untreated.

The third substudy, a systematic literature review and meta-analysis, was informed by the survey findings and the traditional view of methohexital as the gold standard in ECT anaesthesia. The review found that propofol and methohexital appear to be equally effective in terms of treatment response; however, the included studies were dated and generally of low quality, highlighting the need for further research on the topic.