title: Frequency of non-convulsive seizures and non-convulsive status epilepticus in subarachnoid hemorrhage patients in need of controlled ventilation and sedation.
abstract: BACKGROUND
  Non-convulsive seizures (NCSZ) can be more prevalent than previously recognized among comatose neuro-intensive care patients. The aim of this study was to evaluate the frequency of NCSZ and non-convulsive status epilepticus (NCSE) in sedated and ventilated subarachnoid hemorrhage (SAH) patients.
  
  
  METHODS
  Retrospective study at a university hospital neuro-intensive care unit, from January 2008 until June 2010. Patients were treated according to a local protocol, and were initially sedated with midazolam or propofol or combinations of these sedative agents. Thiopental was added for treatment of intracranial hypertension. No wake-up tests were performed. Using NicoletOne(®) equipment (VIASYS Healthcare Inc., USA), continuous EEG recordings based on four electrodes and a reference electrode was inspected at full length both in a two electrode bipolar and a four-channel referential montage.
  
  
  RESULTS
  Approximately 5,500 h of continuous EEG were registered in 28 SAH patients (33 % of the patients eligible for inclusion). The median Glasgow Coma scale was 8 (range 3-14) and the median Hunt and Hess score was 4 (range 1-4). During EEG registration, no clinical seizures were observed. In none of the patients inter ictal epileptiform activity was seen. EEG seizures were recorded only in 2/28 (7 %) patients. One of the patients experienced 4 min of an NCSZ and one had a 5 h episode of an NCSE.
  
  
  CONCLUSIONS
  Continuous EEG monitoring is important in detecting NCSZ in sedated patients. Continuous sedation, without wake-up tests, was associated with a low frequency of subclinical seizures in SAH patients in need of controlled ventilation.
authors.affiliation: Division of Anaesthesiology and Intensive Care, Department of Surgical and Perioperative Sciences, University of Umeå, 90187, Umeå, Sweden. cecilia.lindgren@anestesi.umu.se
authors.forename: Cecilia
authors.initials: C
authors.lastname: Lindgren
authors.forename: Erik
authors.initials: E
authors.lastname: Nordh
authors.forename: Silvana
authors.initials: S
authors.lastname: Naredi
authors.forename: Magnus
authors.initials: M
authors.lastname: Olivecrona
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D016292:Procedural Sedation / Q000706:statistics & numerical data*; D003422:Critical Care / Q000706:statistics & numerical data; D004569:Electroencephalography; D005260:Female; D006801:Humans; D006993:Hypnotics and Sedatives / Q000627:therapeutic use; D007427:Intracranial Pressure; D008297:Male; D008874:Midazolam / Q000627:therapeutic use; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000706:statistics & numerical data; D015995:Prevalence; D015742:Propofol / Q000627:therapeutic use; D012121:Respiration, Artificial / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D013226:Status Epilepticus / Q000175:diagnosis / Q000453:epidemiology* / Q000628:therapy*; D013345:Subarachnoid Hemorrhage / Q000453:epidemiology* / Q000628:therapy*; D013874:Thiopental / Q000627:therapeutic use; D055815:Young Adult
chemical_list: D006993:Hypnotics and Sedatives; D013874:Thiopental; D008874:Midazolam; D015742:Propofol