An Analysis of the Correlation Between the Static and Dynamic Impedance During Electroconvulsive Therapy (ECT)

Gozde Unal, Carliza Canela, Jaiti Swami, Samantha Cohen, Marom Bikson, Department of Biomedical Engineering, The City College of New York, CUNY, NY, USA , 85 St Nicholas Terrace, New York, NY 10031 Niranjan Khadka, Department of Psychiatry, Laboratory for Neuropsychiatry and Neuromodulation, Massachusetts General Hospital, Harvard Medical School, MA, USA, 25 Shattuck St, Boston, MA 02115 Harold Sackeim, Department of Psychiatry, Columbia University, NY, USA, 1051 Riverside Dr, New York, NY 10032

While static impedance and dynamic impedance has long been recognized as markers of individual difference in electroconvulsive therapy (ECT), their etiology and consequence are undetermined – including how they impact seizure generation. A typically high static impedance is relied on to suggest an expected high dynamic impedance, and hence the need to correct electrode setup. Yet, the correlation between individual static impedance and dynamic impedance has remained elusive, with numerous prior studies suggesting it does not exist. This is a retrospective analysis of static impedance, dynamic impedance, seizure charge threshold, and patient demographic data recorded from a total of 90 patients (with a total of 622 ECT daily sessions and 622 ECT stimulations) involved in two previously published clinical trials.  These ECT courses utilized right unilateral (RUL) or bilateral (BL) montage placements, with either 0.3 ms (ultrabrief) or 1.5 ms (brief) pulse duration. Our results demonstrate a correlation between static impedance and dynamic impedance, evident across clinical trial centers, montages, and pulse durations, considering either across session averages or single stimulations. The strength of correlations varied across these conditions, suggesting how they might have been missed in prior analysis.

Additional Abstract Information

Presenters: Carliza Canela, Gozde Unal, Jaiti Swami, Samantha Cohen, Niranjan Khadka, Harold Sackeim, Marom Bikson

Institution: City University of New York- City College

Type: Poster

Subject: Psychology

Status: Approved

Time and Location

Session: Poster 10
Date/Time: Wed 1:30pm-2:30pm
Session Number: 6561