title: Children on phenobarbital monotherapy requires more sedatives during MRI.
abstract: BACKGROUND
  Phenobarbital induces specific hepatic cytochrome P-450 enzyme pathways causing increased clearance of hepatically metabolized drugs. In this study, we investigated the duration and additional anesthetic requirement during Magnetic resonance imaging (MRI) in epileptic children with or without phenobarbital monotherapy.
  
  
  METHODS
  In ASA I-II, 128 children, aged 1-10 years, were included. Group I: epileptic children without anti-epileptic therapy and Group II: children with phenobarbital monotherapy. The initial sedative drugs were 0.1 mg·kg(-1) midazolam with 2 mg·kg(-1) ketamine. An additional 1 mg·kg(-1) ketamine was administrated if required. Rescue propofol (0.5 mg·kg(-1)) was provided and repeated to maintain sedation. The duration and consumption of additional sedative requirements was recorded.
  
  
  RESULTS
  The duration of initial and two consequent additional sedative requirements was shorter in Group II (P = 0.0001, P = 0.001 and P = 0.27, respectively). Additional ketamine doses required for adequate sedation were lower in Group I (P = 0.016).
  
  
  CONCLUSIONS
  We suggest that the variability in response to the initial sedative agents during MRI requires titration of additive sedation with ketamine in epileptic children on phenobarbital monotherapy.
authors.affiliation: Department of Anesthesiology, Baskent University School of Medicine, Ankara, Turkey. evreneker@yahoo.com
authors.forename: Hatice Evren
authors.initials: HE
authors.lastname: Eker
authors.forename: Oya
authors.initials: O
authors.lastname: Yalcin Cok
authors.forename: Anis
authors.initials: A
authors.lastname: Aribogan
authors.forename: Gulnaz
authors.initials: G
authors.lastname: Arslan
mesh_terms: D000778:Anesthetics, Dissociative / Q000008:administration & dosage; D000927:Anticonvulsants / Q000009:adverse effects* / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D016292:Procedural Sedation / Q000379:methods; D004311:Double-Blind Method; D004827:Epilepsy / Q000150:complications / Q000188:drug therapy; D005260:Female; D006801:Humans; D006993:Hypnotics and Sedatives / Q000008:administration & dosage; D007223:Infant; D007649:Ketamine / Q000008:administration & dosage; D008279:Magnetic Resonance Imaging; D008297:Male; D008874:Midazolam / Q000008:administration & dosage; D010634:Phenobarbital / Q000009:adverse effects* / Q000627:therapeutic use; D011446:Prospective Studies; D011997:Recovery Room
chemical_list: D000778:Anesthetics, Dissociative; D000927:Anticonvulsants; D006993:Hypnotics and Sedatives; D007649:Ketamine; D008874:Midazolam; D010634:Phenobarbital