title: Continuous electroencephalographic monitoring in critically ill patients with central nervous system infections.
abstract: OBJECTIVE
  To determine the prevalence, predictors, and clinical significance of electrographic seizures (ESz) and other continuous electroencephalographic monitoring findings in critically ill patients with central nervous system infections.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  Eighteen-bed neurocritical care unit.
  
  
  METHODS
  We identified 42 consecutive patients with primary central nervous system infection (viral, 27 patients [64%]; bacterial, 8 patients [18%]; and fungal or parasitic, 7 patients [17%]) who underwent continuous electroencephalographic monitoring between January 1, 1996, and February 28, 2007.
  
  
  METHODS
  Presence of ESz or periodic epileptiform discharges (PEDs).
  
  
  RESULTS
  Electrographic seizures were recorded in 14 patients (33%), and PEDs were recorded in 17 patients (40%). Twenty patients (48%) had either PEDs or ESz. Of the 14 patients with ESz, only 5 (36%) had a clinical correlate. Periodic epileptiform discharges (odds ratio=13.4; P=.001) and viral cause (odds ratio=13.0; P=.02) were independently associated with ESz. Both ESz (odds ratio=5.9; P=.02) and PEDs (odds ratio=6.1; P=.01) were independently associated with poor outcome at discharge (severe disability, vegetative state, or death).
  
  
  CONCLUSIONS
  In patients with central nervous system infections undergoing continuous electroencephalographic monitoring, ESz and/or PEDs were frequent, occurring in 48% of our cohort. More than half of the ESz had no clinical correlate. Both ESz and PEDs were independently associated with poor outcome. Additional studies are needed to determine whether prevention or treatment of these electrographic findings improves outcome.
authors.affiliation: Comprehensive Epilepsy Center, Columbia University Medical Center, 710 W 168th St, Box NI-135, New York, NY 10032, USA.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Carrera
authors.forename: Jan
authors.initials: J
authors.lastname: Claassen
authors.forename: Mauro
authors.initials: M
authors.lastname: Oddo
authors.forename: Ronald G
authors.initials: RG
authors.lastname: Emerson
authors.forename: Stephan A
authors.initials: SA
authors.lastname: Mayer
authors.forename: Lawrence J
authors.initials: LJ
authors.lastname: Hirsch
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002494:Central Nervous System Infections / Q000145:classification / Q000188:drug therapy / Q000453:epidemiology / Q000503:physiopathology*; D016009:Chi-Square Distribution; D015331:Cohort Studies; D016638:Critical Illness; D004569:Electroencephalography / Q000379:methods*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods; D012189:Retrospective Studies; D012640:Seizures / Q000209:etiology; D018709:Statistics, Nonparametric; D055114:X-Ray Microtomography / Q000379:methods; D055815:Young Adult