title: Inhibitory effects of landiolol and nicardipine on thiopental-induced yawning in humans.
abstract: OBJECTIVE
  Either the calcium (Ca(2+))-channel blocker nicardipine or the beta(1)-adrenoceptor antagonist landiolol may be intravenously (IV) administered to reduce the hemodynamic responses to tracheal intubation. In this study, we examined the effects of these drugs on the yawning response elicited by intravenous thiopental in humans.
  
  
  METHODS
  After Institutional Review Board approval, 180 consenting American Society of Anesthesiologists (ASA) I or II patients undergoing elective surgery were recruited. In a double-blind, randomized design, three groups of 60 patients each received one of the following intravenous injections: (1) landiolol 0.1 mg/kg (L-group), (2) nicardipine 0.02 mg/kg (N-group), or (3) saline (S-group). In all patients, anesthesia was subsequently induced IV with 4 mg/kg thiopental. Thereafter, the occurrence of the yawning response (characterized by mouth opening) was continuously assessed as the only clinical endpoint for 1 min. Throughout the study, mean arterial blood pressure and heart rate were also recorded at 1-min intervals.
  
  
  RESULTS
  The incidence of the yawning response was lower in both the L-group (6.7%) and the N-group (16.7%) than in the S-group (46.7%) (each, P < 0.01).
  
  
  CONCLUSIONS
  Prior intravenous administration of either a Ca(2+)-channel blocker or a beta(1)-adrenoceptor antagonist can greatly reduce the thiopental-induced yawning response in humans.
authors.affiliation: Department of Anesthesia, Gifu Red Cross Hospital, Gifu, 502-8511, Japan. tsutomu.oshima@jfcr.or.jp
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Oshima
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Murakami
authors.forename: Yuhji
authors.initials: Y
authors.lastname: Saitoh
authors.forename: Miyuki
authors.initials: M
authors.lastname: Yokota
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Kasuya
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000494:pharmacology*; D000328:Adult; D001794:Blood Pressure / Q000187:drug effects; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D004311:Double-Blind Method; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006993:Hypnotics and Sedatives / Q000008:administration & dosage / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D009025:Morpholines / Q000494:pharmacology*; D009529:Nicardipine / Q000494:pharmacology*; D013874:Thiopental / Q000008:administration & dosage / Q000009:adverse effects; D014508:Urea / Q000031:analogs & derivatives* / Q000494:pharmacology; D015000:Yawning / Q000187:drug effects* / Q000502:physiology
chemical_list: D000319:Adrenergic beta-Antagonists; D002121:Calcium Channel Blockers; D006993:Hypnotics and Sedatives; D009025:Morpholines; C077049:landiolol; D014508:Urea; D009529:Nicardipine; D013874:Thiopental