Increasing or fluctuating bispectral index values during post-resuscitation targeted temperature management can predict clinical seizures after rewarming.
To investigate whether an increasing bispectral index (BIS) value during targeted temperature management (TTM) correlates with increased clinical seizures after TTM or worse neurological prognoses after TTM.



We performed a retrospective prognostication study of patients who were treated with TTM after recovery of spontaneous circulation from cardiac arrest at a tertiary care hospital. We recorded the BIS regularly during TTM and calculated the correlations of the mean BIS values, standard deviations of the BIS values, and linear regression coefficient of the trend of the BIS values over time as index tests. Study outcomes included the occurrence of clinical seizures after TTM and unfavourable neurological outcomes (defined as a Cerebral Performance Scale score of 3-5). Receiver operating characteristics (ROC) analyses evaluated the predictability of the index tests for the study outcomes.



Of 534 patients with post-cardiac arrest who were admitted to the intensive care unit, 103 were enrolled in this study. Thirty-one patients (30.1%) experienced sequelae in the form of clinical seizures, and 52 (50.5%) had unfavourable neurological outcomes at 30days post-resuscitation. The standard deviation (area under the ROC curve [AUC]=0.763) and the regression coefficient (AUC=0.763) had higher predictability of clinical seizures than the mean BIS value (AUC=0.657); in contrast, the low mean BIS value best predicted unfavourable neurological outcomes (AUC=0.861) compared to the standard deviation (AUC=0.532) and regression coefficient (AUC=0.501).



An increase of, or greater fluctuation in, BIS during hypothermia may predict clinical seizures after TTM.
Department of Acute Critical Care and Disaster Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan.
Kanae
K
Ochiai
Department of Acute Critical Care and Disaster Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan; Emergency and Trauma Center, Kameda Medical Center, 929 Higashicho, Kamogawa City, Chiba 296-8602, Japan. Electronic address: siris.accm@tmd.ac.jp.
Atsushi
A
Shiraishi
Department of Acute Critical Care and Disaster Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan.
Yasuhiro
Y
Otomo
Clinical Research Institute, National Hospital Organization Disaster Medical Center, 3256 Midoricho, Tachikawa City, Tokyo 190-0014, Japan.
Yuuichi
Y
Koido
Department of Critical Care and Traumatology, National Hospital Organization Disaster Medical Center, 3256 Midoricho, Tachikawa City, Tokyo 190-0014, Japan.
Takashi
T
Kanemura
Tottori University Hospital, Emergency & Critical Care Medical Center, 36-1 Nishi-cho, Yonago, Tottori 683-8504, Japan.
Masato
M
Honma
D000368:Aged; D000758:Anesthesia / Q000379:methods; D001831:Body Temperature; D016887:Cardiopulmonary Resuscitation; D003243:Consciousness; D056805:Consciousness Monitors; D004569:Electroencephalography; D005260:Female; D006801:Humans; D006993:Hypnotics and Sedatives / Q000627:therapeutic use; D007036:Hypothermia, Induced / Q000009:adverse effects / Q000379:methods*; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D009125:Muscle Relaxants, Central / Q000627:therapeutic use; D058687:Out-of-Hospital Cardiac Arrest / Q000150:complications / Q000628:therapy*; D011237:Predictive Value of Tests; D017694:Rewarming; D012640:Seizures / Q000209:etiology* / Q000517:prevention & control
D006993:Hypnotics and Sedatives; D009125:Muscle Relaxants, Central
Bispectral index; Post cardiac arrest syndrome; Prognostication study; Seizure; Targeted temperature management