Enhanced Analysis of Somatosensory Evoked Potentials at 20–30 Milliseconds Can Predict Neurological Outcome after Cardiac Arrest

Objective:This study attempted to test the effectiveness of an enhanced analysis of the 20-30 ms com-plex of somatosensory evoked potentials, in predicting the short-term outcome of comatose survivors of out of hospital cardiac arrest and compare it with the current clinical practice. Methods:Single-centre, prospective, observational study. Median nerve SSEP recording performed at 24- 36 h post-return of spontaneous circulation. Recording was analysed using amplitude measurements of P25/30 and Peak-To-Trough of 20-30 ms complex and thresholds to decide P25/30 presence. Neurological outcome was dichotomised into favourable and unfavourable. Results:89 participants were analysed. 43.8% had favourable and 56.2% unfavourable outcome. The sen-sitivity, specificity, positive and negative predictive values of the present SSEP and favourable outcome were calculated. P25/30 presence and size of PTT improved positive predictive value and specificity, while maintained similar negative predictive value and sensitivity, compared to the current practice. Inter-interpreter agreement was also improved. Conclusions:Enhanced analysis of the SSEP at 20-30 ms complex could improve the short-term prognos-tic accuracy for short-term neurological outcome in comatose survivors of cardiac arrest. Significance:Peak-To-Trough analysis of the 20-30 ms SSEP waveform appears to be the best predictor of neurological outcome following out of hospital cardiac arrest. It is also the easiest and most reliable to analyse. & COPY; 2023 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.