The predictive value of highly malignant EEG patterns after cardiac arrest: evaluation of the ERC-ESICM recommendations
Sara Turella, Josef Dankiewicz, Hans Friberg, Janus Christian Jakobsen, Christoph Leithner, Helena Levin, Gisela Lilja, Marion Moseby‐Knappe, Niklas Nielsen, Andrea O. Rossetti, Claudio Sandroni, Frédéric Zubler, Tobias Cronberg, Erik Westhall, the TTM2-trial investigators, Jan Bělohlávek, Clifton W. Callaway, Alain Cariou, Tobias Cronberg, Glenn Eastwood, David Erlinge, Jan Hovdenes, Michael Joannidis, Hans Kirkegaard, Matt Morgan, Alistair Nichol, Per Nordberg, Mauro Oddo, Paolo Pelosi, Christian Rylander, Manoj Saxena, Christian Storm, Fabio Silvio Taccone, Susann Ullén, Matt P. Wise, Paul J. Young, Kathy Rowan, Paul Mouncey, Manu Shankar‐Hari, Duncan Young, Susann Ullén, Theis Lange, Karolina Palmér, Susann Ullén, Ulla-Britt Karlsson, Simon Heissler, Manoj Saxena, Frances Bass, Naomi Hammond, John Myburgh, Colman Taylor, Alain Cariou, Adele Bellino, Marwa Abel-all, Ben Finfer, Carolyn Koch, Yang Li, Anne O’Connor, Julia Pilowsky, Tina Schneider, Anna Tippett, Bridget Ady, Tessa Broadley, Amanda Brown, Liz Melgaard, Mimi Morgan, Vanessa Singh, Rebecca Symons, Kathrin Becker, Nathalie Van Sante, Vendula Saleova, Silvie Zerzanova, Samia Sefr-Kribel, Ute Lübeck, Martina Carrara, Kathryn Fernando, Diane Mackle, Leanlove Navarra, Judith Riley, Elin Westerheim, Marianne Flatebø, Ameldina Ceric, Zana Haxhija, Lovisa Terling, Lena Bossmar, Liz Jergle, Helén Holm Månsson, Samia Abed Maillard, Andreja Vujičić Žagar, Christina Jodlauk, Helen Hill, Jennifer Scrivens, Kate Ainscough, Ciara Fahey, Rinaldo Bellomo, Glenn Eastwood, Leah Peck, Helen Young, Winston Cheung, Rosalba Cross
Abstract
PURPOSE: The 2021 guidelines endorsed by the European Resuscitation Council (ERC) and the European Society of Intensive Care Medicine (ESICM) recommend using highly malignant electroencephalogram (EEG) patterns (HMEP; suppression or burst-suppression) at > 24 h after cardiac arrest (CA) in combination with at least one other concordant predictor to prognosticate poor neurological outcome. We evaluated the prognostic accuracy of HMEP in a large multicentre cohort and investigated the added value of absent EEG reactivity. METHODS: This is a pre-planned prognostic substudy of the Targeted Temperature Management trial 2. The presence of HMEP and background reactivity to external stimuli on EEG recorded > 24 h after CA was prospectively reported. Poor outcome was measured at 6 months and defined as a modified Rankin Scale score of 4-6. Prognostication was multimodal, and withdrawal of life-sustaining therapy (WLST) was not allowed before 96 h after CA. RESULTS: 845 patients at 59 sites were included. Of these, 579 (69%) had poor outcome, including 304 (36%) with WLST due to poor neurological prognosis. EEG was recorded at a median of 71 h (interquartile range [IQR] 52-93) after CA. HMEP at > 24 h from CA had 50% [95% confidence interval [CI] 46-54] sensitivity and 93% [90-96] specificity to predict poor outcome. Specificity was similar (93%) in 541 patients without WLST. When HMEP were unreactive, specificity improved to 97% [94-99] (p = 0.008). CONCLUSION: The specificity of the ERC-ESICM-recommended EEG patterns for predicting poor outcome after CA exceeds 90% but is lower than in previous studies, suggesting that large-scale implementation may reduce their accuracy. Combining HMEP with an unreactive EEG background significantly improved specificity. As in other prognostication studies, a self-fulfilling prophecy bias may have contributed to observed results.