Ictal Electroencephalogram Visual Pattern Recognition of Seizure Adequacy During Electroconvulsive Therapy Treatment: A Step-by-Step Approach.

Background: The NEURON (Neuropsychiatry and Neuromodulation Unit) electroconvulsive therapy electroencephalogram (ECT-EEG) Algorithmic Rating Scale (NEARS) is a step-by-step approach to ictal electroencephalogram visual pattern recognition of seizure adequacy based on recruitment, amplitude, symmetry, duration and degree of post-ictal suppression. The objectives of this clinical audit were to determine the degree of agreement on the NEARS operational criteria between two neuropsychiatrists, the reliability of electroconvulsive therapy practitioners' administration of NEARS during ECT procedures and the correlation of NEARS scores with Clinical Global Impression scale scores after each ECT treatment session.

Methods: Systematic random sampling was conducted. Even numbers of ictal tracings were selected for analysis from the total samples collected over 8 consecutive days of ECT overseen by a total of eight different ECT practitioners. Cohen's kappa coefficient was used to measure the inter-rater reliability of the two neuropsychiatrists and determine the level of agreement between NEARS scores and those of the ECT practitioners. The correlation using NEARS scores and post-ECT Clinical Global Impression scores was measured with Spearman's test. The significance level was set at < 0.05.

Results: Cohen's kappa showed perfect agreement between the two neuropsychiatrists, at κ = 1.00 (SE = 0.001; < 0.001), and strong agreement between NEARS scores of overall seizure adequacy and the scores interpreted by the ECT practitioners, at κ = 0.83 (95% CI: 0.66, 0.99; < 0.001). Spearman's test showed a weak negative association between NEARS scores and post-ECT Clinical Global Impression scores ( = -0.018; = 0.900).

Conclusion: NEARS may facilitate a brief, objectively reliable and practical assessment of ictal electroencephalogram quality. The scale is readily applicable by any trained ECT practitioner during an ongoing ECT procedure, especially when a prompt treatment decision is required.