title: Early Standard Electroencephalogram Abnormalities Predict Mortality in Septic Intensive Care Unit Patients.
abstract: BACKGROUND
  Sepsis is associated with increased mortality, delirium and long-term cognitive impairment in intensive care unit (ICU) patients. Electroencephalogram (EEG) abnormalities occurring at the acute stage of sepsis may correlate with severity of brain dysfunction. Predictive value of early standard EEG abnormalities for mortality in ICU septic patients remains to be assessed.
  
  
  METHODS
  In this prospective, single center, observational study, standard EEG was performed, analyzed and classified according to both Synek and Young EEG scales, in consecutive patients acutely admitted in ICU for sepsis. Delirium, coma and the level of sedation were assessed at the time of EEG recording; and duration of sedation, occurrence of in-ICU delirium or death were assessed during follow-up. Adjusted analyses were carried out using multiple logistic regression.
  
  
  RESULTS
  One hundred ten patients were included, mean age 63.8 (±18.1) years, median SAPS-II score 38 (29-55). At the time of EEG recording, 46 patients (42%) were sedated and 22 (20%) suffered from delirium. Overall, 54 patients (49%) developed delirium, of which 32 (29%) in the days after EEG recording. 23 (21%) patients died in the ICU. Absence of EEG reactivity was observed in 27 patients (25%), periodic discharges (PDs) in 21 (19%) and electrographic seizures (ESZ) in 17 (15%). ICU mortality was independently associated with a delta-predominant background (OR: 3.36; 95% CI [1.08 to 10.4]), absence of EEG reactivity (OR: 4.44; 95% CI [1.37-14.3], PDs (OR: 3.24; 95% CI [1.03 to 10.2]), Synek grade ≥ 3 (OR: 5.35; 95% CI [1.66-17.2]) and Young grade > 1 (OR: 3.44; 95% CI [1.09-10.8]) after adjustment to Simplified Acute Physiology Score (SAPS-II) at admission and level of sedation. Delirium at the time of EEG was associated with ESZ in non-sedated patients (32% vs 10%, p = 0.037); with Synek grade ≥ 3 (36% vs 7%, p< 0.05) and Young grade > 1 (36% vs 17%, p< 0.001). Occurrence of delirium in the days after EEG was associated with a delta-predominant background (48% vs 15%, p = 0.001); absence of reactivity (39% vs 10%, p = 0.003), Synek grade ≥ 3 (42% vs 17%, p = 0.001) and Young grade >1 (58% vs 17%, p = 0.0001).
  
  
  CONCLUSIONS
  In this prospective cohort of 110 septic ICU patients, early standard EEG was significantly disturbed. Absence of EEG reactivity, a delta-predominant background, PDs, Synek grade ≥ 3 and Young grade > 1 at day 1 to 3 following admission were independent predictors of ICU mortality and were associated with occurence of delirium. ESZ and PDs, found in about 20% of our patients. Their prevalence could have been higher, with a still higher predictive value, if they had been diagnosed more thoroughly using continuous EEG.
authors.affiliation: Department of Physiology - Assistance Publique Hôpitaux de Paris, Raymond Poincaré Hospital, U1179 INSERM, University of Versailles Saint-Quentin en Yvelines - Garches, France; General Intensive Care Medicine - Assistance Publique Hôpitaux de Paris, Raymond Poincaré Hospital, U1173 INSERM, University of Versailles Saint-Quentin en Yvelines - Garches, France.
authors.forename: Eric
authors.initials: E
authors.lastname: Azabou
authors.affiliation: General Intensive Care Medicine - Assistance Publique Hôpitaux de Paris, Raymond Poincaré Hospital, U1173 INSERM, University of Versailles Saint-Quentin en Yvelines - Garches, France.
authors.forename: Eric
authors.initials: E
authors.lastname: Magalhaes
authors.affiliation: General Intensive Care Medicine - Assistance Publique Hôpitaux de Paris, Raymond Poincaré Hospital, U1173 INSERM, University of Versailles Saint-Quentin en Yvelines - Garches, France.
authors.forename: Antoine
authors.initials: A
authors.lastname: Braconnier
authors.affiliation: General Intensive Care Medicine - Assistance Publique Hôpitaux de Paris, Raymond Poincaré Hospital, U1173 INSERM, University of Versailles Saint-Quentin en Yvelines - Garches, France.
authors.forename: Lyria
authors.initials: L
authors.lastname: Yahiaoui
authors.affiliation: General Intensive Care Medicine - Assistance Publique Hôpitaux de Paris, Raymond Poincaré Hospital, U1173 INSERM, University of Versailles Saint-Quentin en Yvelines - Garches, France.
authors.forename: Guy
authors.initials: G
authors.lastname: Moneger
authors.affiliation: General Intensive Care Medicine - Assistance Publique Hôpitaux de Paris, Raymond Poincaré Hospital, U1173 INSERM, University of Versailles Saint-Quentin en Yvelines - Garches, France.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Heming
authors.affiliation: General Intensive Care Medicine - Assistance Publique Hôpitaux de Paris, Raymond Poincaré Hospital, U1173 INSERM, University of Versailles Saint-Quentin en Yvelines - Garches, France.
authors.forename: Djillali
authors.initials: D
authors.lastname: Annane
authors.affiliation: Department of Anesthesiology and Intensive Care Medicine - European Hospital Georges Pompidou, Paris Descartes University, Paris, France.
authors.forename: Jean
authors.initials: J
authors.lastname: Mantz
authors.affiliation: Laboratory of Human Histopathology and Animal Models - Institut Pasteur - Paris, France.
authors.forename: Fabrice
authors.initials: F
authors.lastname: Chrétien
authors.affiliation: Department of Physiology - Assistance Publique Hôpitaux de Paris, Raymond Poincaré Hospital, U1179 INSERM, University of Versailles Saint-Quentin en Yvelines - Garches, France.
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Durand
authors.affiliation: Department of Physiology - Assistance Publique Hôpitaux de Paris, Raymond Poincaré Hospital, U1179 INSERM, University of Versailles Saint-Quentin en Yvelines - Garches, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Lofaso
authors.affiliation: Department of Statistics - Assistance Publique Hôpitaux de Paris, Hotel Dieu Hospital, University of René Descartes (Paris V) - Paris, France.
authors.forename: Raphael
authors.initials: R
authors.lastname: Porcher
authors.affiliation: General Intensive Care Medicine - Assistance Publique Hôpitaux de Paris, Raymond Poincaré Hospital, U1173 INSERM, University of Versailles Saint-Quentin en Yvelines - Garches, France; Laboratory of Human Histopathology and Animal Models - Institut Pasteur - Paris, France.
authors.forename: Tarek
authors.initials: T
authors.lastname: Sharshar
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000503:physiopathology; D015331:Cohort Studies; D004569:Electroencephalography; D005260:Female; D006801:Humans; D007362:Intensive Care Units; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011446:Prospective Studies; D018805:Sepsis / Q000401:mortality* / Q000503:physiopathology; D012720:Severity of Illness Index; D016019:Survival Analysis