title: Clinical evaluation of the Abbott Qvue-OptiQ continuous cardiac output system in critically ill medical patients.
abstract: OBJECTIVE
  The aim of this study was to evaluate the reliability of a new continuous cardiac output (CCO) monitoring device (Qvue/OptiQ system; Abbott Critical Care Systems, Mountain View, CA) based on the pulsed warm thermodilution technique in critically ill medical patients.
  
  
  METHODS
  Nineteen patients with cardiogenic or septic shock were included in the study. Pairs of CCO and intermittent bolus cardiac output (ICO) were noted at least every 6 hours for determination of bias, precision, and limits of agreement. Simultaneously, blood samples were collected, and arterial-venous oxygen content difference (C[a-v]O2) was determined. A multiple stepwise logistic regression was used to identify situations associated with a CCO-ICO difference exceeded 20%. A multiple linear regression was performed to analyze the respective accuracy of CCO and ICO to predict the variations of C[a-v]O2.
  
  
  RESULTS
  A total of 203 pairs of cardiac output measurements was obtained. The bias was 0.12 L/min (1.2% of pairs mean) and the precision 1.0 L/min (13%). The 95% limits of agreement were between -1.7 L/min (-25%) and 1.9 L/min (+26%). Low blood temperatures and heart rates above 120 beats/min were significantly associated with a ICO-CCO difference higher than 20%. In a multiple linear regression, CCO was significantly correlated with C[a-v]O2, an independent reflection of the patient's cardiac output; by contrast, ICO did not.
  
  
  CONCLUSIONS
  These results suggest that ICO and CCO measurement by the Qvue/OptiQ system are interchangeable, except for temperature or heart rate extreme values.
authors.affiliation: Medical Intensive Care Unit of Cochin-Port-Royal University Hospital, Paris, France. mehran.monchi@cch.ap-hop-paris.fr
authors.forename: M
authors.initials: M
authors.lastname: Monchi
authors.forename: D
authors.initials: D
authors.lastname: Thebert
authors.forename: A
authors.initials: A
authors.lastname: Cariou
authors.forename: F
authors.initials: F
authors.lastname: Bellenfant
authors.forename: L M
authors.initials: LM
authors.lastname: Joly
authors.forename: F
authors.initials: F
authors.lastname: Brunet
authors.forename: J F
authors.initials: JF
authors.lastname: Dhainaut
mesh_terms: D002302:Cardiac Output / Q000502:physiology*; D002408:Catheters, Indwelling; D003422:Critical Care; D006801:Humans; D008991:Monitoring, Physiologic / Q000295:instrumentation*; D010100:Oxygen / Q000097:blood; D012680:Sensitivity and Specificity; D012770:Shock, Cardiogenic / Q000503:physiopathology* / Q000628:therapy; D012772:Shock, Septic / Q000503:physiopathology* / Q000628:therapy; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation; D013815:Thermodilution / Q000295:instrumentation*
chemical_list: D010100:Oxygen