title: [Appropriate dose of remifentanil to blunt tracheal intubation stress response in patients with severe aortic stenosis].
abstract: BACKGROUND
  In anesthetic induction of patients with severe aortic stenosis, maintenance of normal heart rate and blood pressure is critical. Remifentanil can blunt cardiovascular responses to tracheal intubation, but may cause circulatory collapse due to potent vasodilating effect. We studied retrospectively the optimal dose of remifentanil, which blunts cardiovascular responses to tracheal intubation and provides the hemodynamic stability to patients with severe aortic stenosis.
  
  
  METHODS
  We administerd remifentanil with three different doses (0.3 microg x kg(-1) x min(-1) : n=4, 0.5 microg x kg(-1) x min(-1): n=7, 1 microg x kg(-1) x min(-1): n=7) in anesthetic induction of patients with aortic stenosis. Systolic arterial blood pressure and heart rate before and after the tracheal intubation were recorded. The degree of change of post to pre-intubation of systolic arterial pressure and heart rate was calculated and compared among groups.
  
  
  RESULTS
  There were no significant differences in background among the groups. The ratio between before and after tracheal intubation of systolic arterial pressure was significantly lower in the group of 0.5 microg x kg(-1) x min(-1) and 1 microg x kg(-1) x min(-1). There was no significant hypotension or bradycardia which may lead to severe cardiovascular depression.
  
  
  CONCLUSIONS
  We found that more than 0.5 microg x kg(-1) x min(-1) of remifentanil can blunt cardiovascular responses to tracheal intubation without severe cardiovascular depression.
authors.affiliation: Department of Anesthesia, Kyoto University Hospital, Kyoto 606-8507.
authors.forename: Shino
authors.initials: S
authors.lastname: Matsukawa
authors.forename: Hisanari
authors.initials: H
authors.lastname: Ishii
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Fukuda
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D018686:Anesthetics, Intravenous / Q000008:administration & dosage*; D001024:Aortic Valve Stenosis / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D019918:Heart Valve Prosthesis Implantation; D006439:Hemodynamics; D006801:Humans; D006993:Hypnotics and Sedatives / Q000008:administration & dosage*; D007442:Intubation, Intratracheal / Q000009:adverse effects*; D008297:Male; D010880:Piperidines / Q000008:administration & dosage*; D000077208:Remifentanil; D012189:Retrospective Studies; D012720:Severity of Illness Index
chemical_list: D018686:Anesthetics, Intravenous; D006993:Hypnotics and Sedatives; D010880:Piperidines; D000077208:Remifentanil