title: Preoperative stellate ganglion blockade prevents tourniquet-induced hypertension during general anesthesia.
abstract: BACKGROUND
  Prolonged and excessive inflation of pneumatic tourniquets leads to a hyperdynamic circulatory response. Sympathomimetic activity is an important factor in tourniquet-induced hypertension. Stellate ganglion block specifically blunts sympathetic efferent nerves and prevents hypertension induced by sympathomimetic stimulation. The present study was performed to investigate the effects of stellate ganglion block (SGB) on arterial pressure and heart rate during prolonged tourniquet use under general anesthesia.
  
  
  METHODS
  Twenty patients scheduled for knee arthroscopy were either treated with 10 ml of 1% lidocaine for SGB (SGB group; n = 10), or intramuscular injection (IM group; n = 10) before tourniquet inflation. Comparisons of systolic and diastolic arterial pressure and heart rate were made before and after the induction of anesthesia, 10 min after the lidocaine treatment, every 5 min during the first 60 min after tourniquet inflation, and immediately before and 5 min following deflation. The maximum values of the circulatory variables were compared.
  
  
  RESULTS
  Tourniquet inflation caused increases in the circulatory variables in both groups. Systolic arterial pressure in the SGB group was significantly lower than that in the IM group after 55 min of tourniquet inflation. Diastolic arterial pressure also was significantly lower in the SGB group immediately before the deflation. The maximum values of the three hemodynamic variables were significantly lower in the SGB group. Arterial pressure significantly decreased after tourniquet deflation in the IM group.
  
  
  CONCLUSIONS
  Ipsilateral SGB attenuated the hyperdynamic response mediated by prolonged tourniquet inflation during knee arthroscopy.
authors.affiliation: Department of Anesthesiology, Ehime Rosai Hospital, Ehime, Japan. arainon@med.kochi-ms.ac.jp
authors.forename: Y-C P
authors.initials: YC
authors.lastname: Arai
authors.forename: J
authors.initials: J
authors.lastname: Ogata
authors.forename: Y
authors.initials: Y
authors.lastname: Matsumoto
authors.forename: H
authors.initials: H
authors.lastname: Yonemura
authors.forename: K
authors.initials: K
authors.lastname: Kido
authors.forename: T
authors.initials: T
authors.lastname: Uchida
authors.forename: W
authors.initials: W
authors.lastname: Ueda
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D000768:Anesthesia, General; D000779:Anesthetics, Local / Q000008:administration & dosage / Q000627:therapeutic use; D001182:Arthroscopy; D001340:Autonomic Nerve Block / Q000379:methods*; D001794:Blood Pressure / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000517:prevention & control*; D007273:Injections, Intramuscular; D007717:Knee / Q000601:surgery; D008012:Lidocaine / Q000008:administration & dosage / Q000627:therapeutic use; D011300:Preoperative Care / Q000379:methods*; D013233:Stellate Ganglion; D013997:Time Factors; D014111:Tourniquets / Q000009:adverse effects*
chemical_list: D000779:Anesthetics, Local; D008012:Lidocaine