title: Arterial dP/dtmax accurately reflects left ventricular contractility during shock when adequate vascular filling is achieved.
abstract: BACKGROUND
  Peak first derivative of femoral artery pressure (arterial dP/dtmax) derived from fluid-filled catheter remains questionable to assess left ventricular (LV) contractility during shock. The aim of this study was to test if arterial dP/dtmax is reliable for assessing LV contractility during various hemodynamic conditions such as endotoxin-induced shock and catecholamine infusion.
  
  
  METHODS
  Ventricular pressure-volume data obtained with a conductance catheter and invasive arterial pressure obtained with a fluid-filled catheter were continuously recorded in 6 anaesthetized and mechanically ventilated pigs. After a stabilization period, endotoxin was infused to induce shock. Catecholamines were transiently administrated during shock. Arterial dP/dtmax was compared to end-systolic elastance (Ees), the gold standard method for assessing LV contractility.
  
  
  RESULTS
  Endotoxin-induced shock and catecholamine infusion lead to significant variations in LV contractility. Overall, significant correlation (r=0.51; p<0.001) but low agreement between the two methods were observed. However, a far better correlation with a good agreement were observed when positive-pressure ventilation induced an arterial pulse pressure variation (PPV)≤11% (r=0.77; p<0.001).
  
  
  CONCLUSIONS
  While arterial dP/dtmax and Ees were significantly correlated during various hemodynamic conditions, arterial dP/dtmax was more accurate for assessing LV contractility when adequate vascular filling, defined as PPV≤11%, was achieved.
authors.affiliation: Medical Intensive Care Unit, Emergency Department, University Hospital of Liège, and Faculty of Sciences, University of Liège, Liège, Belgium. ph.morimont@chu.ulg.ac.be
authors.forename: Philippe
authors.initials: P
authors.lastname: Morimont
authors.forename: Bernard
authors.initials: B
authors.lastname: Lambermont
authors.forename: Thomas
authors.initials: T
authors.lastname: Desaive
authors.forename: Nathalie
authors.initials: N
authors.lastname: Janssen
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Chase
authors.forename: Vincent
authors.initials: V
authors.lastname: D'Orio
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000502:physiology*; D005260:Female; D005263:Femoral Artery / Q000502:physiology / Q000503:physiopathology; D006352:Heart Ventricles / Q000503:physiopathology*; D006439:Hemodynamics / Q000502:physiology; D008297:Male; D009200:Myocardial Contraction / Q000502:physiology*; D011175:Positive-Pressure Respiration; D012769:Shock / Q000139:chemically induced / Q000503:physiopathology*; D013552:Swine; D016277:Ventricular Function, Left / Q000502:physiology*; D017725:Ventricular Pressure / Q000502:physiology