title: Clinical validation of pulse contour and pulse wave transit time-based continuous cardiac output analyses in Thai patients undergoing cardiac surgery.
abstract: OBJECTIVE
  To evaluate the performance of arterial pressure-based cardiac output (APCO) and pulse wave transit time-based cardiac output (esCCO) monitors in Thai patients undergoing cardiac surgery with cardiopulmonary bypass.
  
  
  METHODS
  The authors studied fifty Thai surgical patients undergoing coronary artery bypass graft surgery (CABG) with cardiopulmonary bypass and requiring pulmonary artery catheters and radial artery catheter placement as a standard of clinical care. All patients were measured for APCO using the Vigileo/FloTrac and esCCO using the esCCO monitoring system. The data were compared to thermodilution cardiac output (TDCO) monitoring as a reference method, simultaneously at pre-induction of anesthesia, post-induction, and every 30 minutes thereafter until the completion of the surgery. The bias and precision were assessed using Bland-Altman analysis.
  
  
  RESULTS
  310 pairs of simultaneous measurements of APCO vs. TDCO and 303 pairs of esCCO vs. TDCO were obtained from fifty patients. Both APCO (R = 0.53, p < 0.0001) and esCCO values (R = 0.56, p < 0.0001) were correlated with TDCO values. Either of the changes in APCO (R = 0.63, p < 0.0001) or any changes in esCCO (R = 0.60, p < 0.0001) were correlated with changes in TDCO. For APCO relative to TDCO, the bias, precision, and the limits of agreement were 0.70, +/- 1.63, and -2.5 to 3.9 L/min while of esCCO were 1.20, +/-1.59 and -1.9 to 4.3 L/min, respectively. Comparisons of the bias of APCO and esCCO revealed a level of significance of p < 0.001.
  
  
  CONCLUSIONS
  Despite the overestimation of CO measurements, APCO and esCCO calibrated with patient information has shown an acceptable trend as compared to TDCO in Thai patients undergoing CABG with cardiopulmonary bypass. Compared to esCCO, APCO demonstrated no significant differences ofprecision however; a lower mean bias was exhibited.
authors.forename: Petch
authors.initials: P
authors.lastname: Wacharasint
authors.forename: Pimsai
authors.initials: P
authors.lastname: Kunakorn
authors.forename: Pimporn
authors.initials: P
authors.lastname: Pankongsap
authors.forename: Ratanachai
authors.initials: R
authors.lastname: Preechanukul
mesh_terms: D000328:Adult; D000368:Aged; D001783:Blood Flow Velocity / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology; D006328:Cardiac Catheterization; D002302:Cardiac Output / Q000502:physiology*; D002315:Cardiopulmonary Bypass; D015331:Cohort Studies; D001026:Coronary Artery Bypass; D003327:Coronary Disease / Q000503:physiopathology* / Q000601:surgery; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D063177:Pulse Wave Analysis; D015203:Reproducibility of Results; D013785:Thailand; D013815:Thermodilution