title: Dose-dependent hemodynamic effects of propofol induction following brotizolam premedication in hypertensive patients taking angiotensin-converting enzyme inhibitors.
abstract: OBJECTIVE
  To determine a propofol dose that minimizes hemodynamic changes on induction of anesthesia in patients chronically taking angiotensin-converting enzyme inhibitors (ACEIs).
  
  
  METHODS
  Prospective, randomized trial.
  
  
  METHODS
  Operating room of a university-affiliated general hospital.
  
  
  METHODS
  88 ASA physical status II and II hypertensive patients chronically taking ACEIs, scheduled for elective abdominal surgery with general anesthesia.
  
  
  METHODS
  Patients were premedicated with brotizolam and anesthesia was induced with propofol, fentanyl, and rocuronium; anesthesia was then maintained with isoflurane. Patients were randomly assigned to undergo anesthetic induction with propofol in doses of 1.3, 1.6, 2.0, or 2.3 mg/kg.
  
  
  METHODS
  Oscillometric blood pressure and heart rate were evaluated at one-minute intervals during the first 10 minutes of anesthesia. End-tidal isoflurane concentrations were also recorded. Episodes of hypertension, tachycardia, bradycardia, or hypotension (defined as > 30% of baseline values) were managed per protocol with esmolol, atropine, phenylephrine, or ephedrine. Administration of any of these drugs was considered a pharmacological intervention.
  
  
  RESULTS
  After adjusting for covariables in a model assuming a linear relationship between dose and log-response, each propofol dose increase of 0.3 mg/kg was associated with a 31% increase in mean number of hypotensive/bradycardic episodes requiring interventions (95% confidence intervals of +5% and +65%; P = 0.018). Based on our model, a dose of 1.3 mg/kg resulted in the fewest number of pharmacological interventions.
  
  
  CONCLUSIONS
  In patients chronically taking ACEIs, low doses of propofol reduce hemodynamic instability.
authors.affiliation: Department of Anesthesia, Edith Wolfson Medical Center, Holon, Israel.
authors.forename: Marian
authors.initials: M
authors.lastname: Weisenberg
authors.forename: Daniel I
authors.initials: DI
authors.lastname: Sessler
authors.forename: Monica
authors.initials: M
authors.lastname: Tavdi
authors.forename: Muzikant
authors.initials: M
authors.lastname: Gleb
authors.forename: Tiberiu
authors.initials: T
authors.lastname: Ezri
authors.forename: Jarrod E
authors.initials: JE
authors.lastname: Dalton
authors.forename: Michael
authors.initials: M
authors.lastname: Protianov
authors.forename: Reuven
authors.initials: R
authors.lastname: Zimlichmann
mesh_terms: D000328:Adult; D000368:Aged; D018686:Anesthetics, Intravenous / Q000008:administration & dosage*; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000008:administration & dosage*; D001381:Azepines / Q000008:administration & dosage*; D001794:Blood Pressure / Q000187:drug effects; D001919:Bradycardia / Q000188:drug therapy; D004305:Dose-Response Relationship, Drug; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000188:drug therapy*; D006993:Hypnotics and Sedatives / Q000008:administration & dosage*; D007022:Hypotension / Q000188:drug therapy; D008875:Middle Aged; D011229:Preanesthetic Medication; D015742:Propofol / Q000008:administration & dosage*; D011446:Prospective Studies; D013610:Tachycardia / Q000188:drug therapy
chemical_list: D018686:Anesthetics, Intravenous; D000806:Angiotensin-Converting Enzyme Inhibitors; D001381:Azepines; D006993:Hypnotics and Sedatives; C020960:brotizolam; D015742:Propofol