title: Frontal Intermittent Rhythmic Delta Activity (FIRDA) in the Neurological Intensive Care: Prevalence, Determinants, and Clinical Significance.
abstract: BACKGROUND
  Frontal intermittent rhythmic delta activity (FIRDA), a transient rhythmic slow wave pattern over the anterior EEG leads, has been reported in a wide variety of cerebral lesions and different metabolic disturbances. Few authors have analyzed the frequency and clinical significance of FIRDA in the critical care setting. We aimed to better understand these issues in our intensive care cohort and if possible, try to delineate its underlying mechanisms.
  
  
  METHODS
  Video-EEG reports of consecutive adult patients in the neurological intensive care unit (NICU) since 2009 were retrospectively reviewed to identify cases with FIRDA. Demographic, clinical, and laboratory data were obtained from EEG reports and patient charts. Age- and sex-matched patients with acute stroke, hospitalized in NICU and no FIRDA on video-EEG monitoring served as the control group.
  
  
  RESULTS
  Among 162 patients who underwent video-EEG monitoring, FIRDA was documented in 17%. Female prevalence was 50% and age ranged from 23 to 82 years. Twenty-three (82%) of patients with FIRDA had a diagnosis of stroke. Comparison of demographic characteristics, EEG findings, metabolic disturbances and prognoses revealed no differences between stroke cases with and without FIRDA, except for higher frequency of acute and chronic isolated posterior circulation infarcts in patients with FIRDA.
  
  
  CONCLUSIONS
  FIRDA is more commonly encountered in the neurocritical care setting as compared with outpatient EEG clinics. Our findings in stroke patients indicate that involved vascular territories may be related to the generation of FIRDA.
authors.affiliation: 1 Department of Neurology, Faculty of Medicine, Hacettepe University, Ankara, Turkey.
authors.forename: Nese
authors.initials: N
authors.lastname: Dericioglu
authors.affiliation: 1 Department of Neurology, Faculty of Medicine, Hacettepe University, Ankara, Turkey.
authors.forename: Farid
authors.initials: F
authors.lastname: Khasiyev
authors.affiliation: 1 Department of Neurology, Faculty of Medicine, Hacettepe University, Ankara, Turkey.
authors.forename: E Murat
authors.initials: EM
authors.lastname: Arsava
authors.affiliation: 1 Department of Neurology, Faculty of Medicine, Hacettepe University, Ankara, Turkey.
authors.forename: M Akif
authors.initials: MA
authors.lastname: Topcuoglu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003422:Critical Care; D003700:Delta Rhythm / Q000502:physiology*; D004569:Electroencephalography / Q000379:methods; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012189:Retrospective Studies; D020521:Stroke / Q000453:epidemiology / Q000503:physiopathology*
keywords: EEG; intensive care; intermittent rhythmic delta activity; pathophysiology; stroke