title: Hemodynamics of pancreatic ischemia in cardiogenic shock in pigs.
abstract: OBJECTIVE
  Previous studies have shown that the renin-angiotensin axis plays a pivotal role in vasoconstriction of the gastric, intestinal, and hepatic circulations during cardiogenic shock. The aim of this study was to evaluate the fundamental hemodynamic mechanism of pancreatic ischemia during cardiogenic shock induced by pericardial tamponade.
  
  
  METHODS
  Cardiogenic shock was induced by pericardial tamponade. Cardiac output (and total peripheral vascular resistance) was determined by thermodilution. Pancreatic blood flow (and vascular resistance) was determined with radiolabeled microspheres.
  
  
  RESULTS
  Graded increases in pericardial pressure produced corresponding decreases in cardiac output to 42% +/- 1% and arterial pressure to 67% +/- 3% of baseline and increases in total peripheral vascular resistance to 146% +/- 5% of baseline. Pancreatic blood flow decreased disproportionately to 30% +/- 3% of baseline, because of a disproportionate increase in pancreatic vascular resistance to 220% +/- 19% of baseline. Previously confirmed blockade of the renin-angiotensin axis ablated this response, whereas confirmed blockade of the alpha-adrenergic system or vasopressin system had no significant effect. Without shock, central intravenous infusions of angiotensin II closely mimicked this selective vasoconstriction.
  
  
  CONCLUSIONS
  Angiotensin-mediated selective pancreatic vasoconstriction results in significant pancreatic ischemia during cardiogenic shock.
authors.affiliation: Department of Surgery, Johns Hopkins Medical Institutions, Baltimore, Maryland, USA.
authors.forename: P M
authors.initials: PM
authors.lastname: Reilly
authors.forename: T J
authors.initials: TJ
authors.lastname: Toung
authors.forename: M
authors.initials: M
authors.lastname: Miyachi
authors.forename: H J
authors.initials: HJ
authors.lastname: Schiller
authors.forename: G B
authors.initials: GB
authors.lastname: Bulkley
mesh_terms: D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology; D000818:Animals; D000831:Animals, Newborn; D002305:Cardiac Tamponade / Q000503:physiopathology; D004656:Enalapril / Q000494:pharmacology; D006439:Hemodynamics; D007511:Ischemia / Q000503:physiopathology*; D010179:Pancreas / Q000098:blood supply*; D010643:Phenoxybenzamine / Q000494:pharmacology; D012039:Regional Blood Flow; D012770:Shock, Cardiogenic / Q000503:physiopathology*; D013552:Swine
chemical_list: D000317:Adrenergic alpha-Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors; D010643:Phenoxybenzamine; D004656:Enalapril