title: Effects of chronic angiotensin II receptor antagonist and angiotensin-converting enzyme inhibitor treatments on neurohormonal levels and haemodynamics during cardiopulmonary bypass.
abstract: BACKGROUND
  Chronic treatment with renin-angiotensin system (RAS) antagonists frequently causes deleterious hypotension during anaesthesia. We compared the effects of angiotensin II receptor antagonists (ARA) and angiotensin-converting enzyme inhibitors (ACEI) on neurohormonal levels and haemodynamics during cardiopulmonary bypass (CPB).
  
  
  METHODS
  Forty-four patients undergoing mitral valvular surgery who were treated with either ARA (ARA group, n=14) or ACEI (ACEI group, n=15) over 12 weeks or who were not treated with any RAS antagonist (control group, n=15) were enrolled. The plasma levels of epinephrine, norepinephrine, arginine vasopressin (AVP) and angiotensin II, and haemodynamic variables were measured before (T1) and 15 min after (T2) the start of CPB, before aortic unclamping (T3) and at skin closure (T4). Mean arterial pressure (MAP) was maintained above 60 mm Hg with phenylephrine administration during CPB.
  
  
  RESULTS
  The plasma epinephrine, norepinephrine, AVP and angiotensin II levels increased during CPB in all groups. Compared with the control group, the AVP level was lower at T1 in the ARA group and at T2 in the ARA and ACEI groups. The angiotensin II level was higher at T1, T2 and T3 in ARA group compared with ACEI and control groups. There were no significant differences in the epinephrine and norepinephrine levels among the three groups. The amount of administered phenylephrine during CPB was greater and MAP was lower in the ARA group compared with the ACEI and control groups.
  
  
  CONCLUSIONS
  Chronic ARA treatment resulted in more profound hypotension than ACEI treatment during CPB, and this may be associated with the blockade of angiotensin II receptors by ARA.
authors.affiliation: Department of Anaesthesiology and Pain Medicine, Anaesthesia and Pain Research Institute, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Y J
authors.initials: YJ
authors.lastname: Oh
authors.forename: J H
authors.initials: JH
authors.lastname: Lee
authors.forename: S B
authors.initials: SB
authors.lastname: Nam
authors.forename: J K
authors.initials: JK
authors.lastname: Shim
authors.forename: J H
authors.initials: JH
authors.lastname: Song
authors.forename: Y L
authors.initials: YL
authors.lastname: Kwak
mesh_terms: D000328:Adult; D000368:Aged; D057911:Angiotensin Receptor Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000009:adverse effects / Q000494:pharmacology*; D001794:Blood Pressure / Q000187:drug effects; D002302:Cardiac Output / Q000187:drug effects; D002315:Cardiopulmonary Bypass; D004334:Drug Administration Schedule; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007022:Hypotension / Q000139:chemically induced; D007431:Intraoperative Complications; D007432:Intraoperative Period; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000601:surgery; D018377:Neurotransmitter Agents / Q000097:blood*; D010656:Phenylephrine / Q000008:administration & dosage; D012084:Renin-Angiotensin System / Q000187:drug effects; D014662:Vasoconstrictor Agents / Q000008:administration & dosage
chemical_list: D057911:Angiotensin Receptor Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors; D018377:Neurotransmitter Agents; D014662:Vasoconstrictor Agents; D010656:Phenylephrine