title: Prostaglandin E1 attenuates the hypertensive response to tracheal extubation.
abstract: OBJECTIVE
  Tracheal extubation causes hypertension and tachycardia, which may cause imbalance between myocardial oxygen demand and supply in patients at risk of coronary artery disease. We conducted a randomized, controlled study to evaluate the effects of 0.05 or 0.1 microgram.kg-1.min-1 prostaglandin E1 (PGE1) iv on haemodynamic variables occurring during tracheal extubation and emergence from anaesthesia and compared them in patients receiving either lidocaine or saline.
  
  
  METHODS
  Eighty ASA physical status 1 patients undergoing elective surgery were enrolled in the current study. Anaesthesia was maintained with sevoflurane 1.0%-2.5% (ET concentration) and nitrous oxide 60% in oxygen. Muscle relaxation was achieved with vecuronium. The patients were randomly assigned to receive one of four treatments (n = 20 each): saline (control), 0.05 microgram.kg-1.min-1 PGE1, 0.1 microgram.kg-1.min-1 PGE1, or 1 mg.kg-1 lidocaine. PGE1 was infused from completion of surgery until five minutes after tracheal extubation. Changes in heart rate (HR) and blood pressure (BP) were measured during and after tracheal extubation.
  
  
  RESULTS
  In the control group, the HR, systolic BP, and diastolic BP increased during tracheal extubation. Administration of 0.1 microgram.kg-1.min-1 PGE1 and 1 mg.kg-1 lidocaine attenuated the increases in BP although 0.05 microgram.kg-1.min-1 PGE1 failed to do so. The inhibitory effect of the 0.1 microgram.kg-1.min-1 PGE1 on BP was similar to that of lidocaine 1 mg.kg-1 iv. The increase in HR was attenuated by lidocaine but not by PGE1.
  
  
  CONCLUSIONS
  The intravenous infusion of 0.1 microgram.kg-1.min-1 PGE1 given during emergence from anaesthesia and tracheal extubation is a useful method for attenuating the hypertension associated with noxious stimuli during this period.
authors.affiliation: Department of Anaesthesiology, Kobe University School of Medicine, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Nishina
authors.forename: K
authors.initials: K
authors.lastname: Mikawa
authors.forename: M
authors.initials: M
authors.lastname: Shiga
authors.forename: N
authors.initials: N
authors.lastname: Maekawa
authors.forename: H
authors.initials: H
authors.lastname: Obara
mesh_terms: D000328:Adult; D000527:Alprostadil / Q000494:pharmacology*; D001794:Blood Pressure / Q000187:drug effects*; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007442:Intubation, Intratracheal; D008297:Male
chemical_list: D000527:Alprostadil