title: Burst suppression on processed electroencephalography as a predictor of postcoma delirium in mechanically ventilated ICU patients.
abstract: OBJECTIVE
  Many patients, due to a combination of illness and sedatives, spend a considerable amount of time in a comatose state that can include time in burst suppression. We sought to determine if burst suppression measured by processed electroencephalography during coma in sedative-exposed patients is a predictor of post-coma delirium during critical illness.
  
  
  METHODS
  Observational convenience sample cohort.
  
  
  METHODS
  Medical and surgical ICUs in a tertiary care medical center.
  
  
  METHODS
  Cohort of 124 mechanically ventilated ICU patients.
  
  
  METHODS
  None.
  
  
  RESULTS
  Depth of sedation was monitored twice daily using the Richmond Agitation-Sedation Scale and continuously monitored by processed electroencephalography. When noncomatose, patients were assessed for delirium twice daily using Confusion Assessment Method for the ICU. Multiple logistic regression and Cox proportional hazards regression were used to assess associations between time in burst suppression and both prevalence and time to resolution of delirium, respectively, adjusting for time in deep sedation and a principal component score consisting of Acute Physiology and Chronic Health Evaluation II score and cumulative doses of sedatives while comatose. Of the 124 patients enrolled and monitored, 55 patients either never had coma or never emerged from coma, yielding 69 patients for whom we performed these analyses; 42 of these 69 (61%) had post-coma delirium. Most patients had burst suppression during coma, although often short-lived (median [interquartile range] time in burst suppression, 6.4 [1-58] min). After adjusting for covariates, even this short time in burst suppression independently predicted a higher prevalence of post-coma delirium (odds ratio, 4.16; 95% CI, 1.27-13.62; p = 0.02) and a lower likelihood (delayed) resolution of delirium (hazard ratio, 0.78; 95% CI, 0.53-0.98; p = 0.04).
  
  
  CONCLUSIONS
  Time in burst suppression during coma, as measured by processed electroencephalography, was an independent predictor of prevalence and time to resolution of postcoma/post-deep sedation delirium. These findings of this single-center investigation support lighter sedation strategies.
authors: 1Department of Pediatrics, Children's Hospital of Pittsburgh, Pittsburgh, PA. 2Division of Allergy, Pulmonary, and Critical Care Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN. 3Center for Health Services Research, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN. 4Geriatric Research, Education, and Clinical Center Service, Department of Veterans Affairs Medical Center, Tennessee Valley Healthcare System, Nashville, TN. 5Anesthesia Service, Department of Veterans Affairs Medical Center, Tennessee Valley Healthcare System, Nashville, TN. 6Division of Critical Care, Department of Anesthesia, Vanderbilt University Medical Center, Nashville, TN. 7Department of Biostatistics, Vanderbilt University Medical Center, Nashville, TN.
authors: Jennifer M
authors: JM
authors: Andresen
authors: Timothy D
authors: TD
authors: Girard
authors: Pratik P
authors: PP
authors: Pandharipande
authors: Mario A
authors: MA
authors: Davidson
authors: E Wesley
authors: EW
authors: Ely
authors: Paula L
authors: PL
authors: Watson
mesh_terms: D018806:APACHE; D000368:Aged; D001921:Brain / Q000503:physiopathology; D003128:Coma / Q000150:complications / Q000503:physiopathology*; D054810:Deep Sedation / Q000009:adverse effects / Q000706:statistics & numerical data*; D003693:Delirium / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D004569:Electroencephalography / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007362:Intensive Care Units / Q000706:statistics & numerical data; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012121:Respiration, Artificial / Q000009:adverse effects / Q000706:statistics & numerical data*