title: The value of arterial pressure waveform cardiac output measurements in the radial and femoral artery in major cardiac surgery patients.
abstract: A relatively new uncalibrated arterial pressure waveform cardiac output (CO) measurement technique is the Pulsioflex-ProAQT® system. Aim of this study was to validate this system in cardiac surgery patients with a specific focus on the evaluation of a difference in the radial versus the femoral arterial access, the value of the auto-calibration modus and the ability to show fluid-induced changes.
  
  
  
  In twenty-five patients scheduled for ascending aorta, aortic arch replacement, or both we measured CO simultaneously by transpulmonary thermodilution (COtd) and by using the ProAQT® system connected to the radial (COpR), as well as the femoral artery catheter (COpF). Hemodynamic data were assessed at predefined time points; from incision until 16 h after ICU admission.
  
  
  
  In total 175 (radial) and 179 (femoral) pairs of CO measurement were collected. The accuracy of COpR/COpF was evaluated showing a mean bias of -0.31 L/min (±2.9 L/min) and -0.57 L/min (± 2.8 L/min) with percentage errors of 49 and 46% respectively. Trending ability of the ProAQT® device was evaluated; the four quadrant concordance rates in the radial and femoral artery were 74 and 75% and improved to 77 and 85% after auto-calibration. The mean angular biases in the radial and femoral artery were 6.4° and 6.0° and improved to 5° and 3.3° after auto-calibration. The polar concordance rates in the radial and femoral artery were 65 and 70% and improved to 76 and 84% after auto-calibration. Considering the fluid-induced changes in stroke volume(SV), the coefficient of correlation between the changes in SVtd and SVp was 0.57 (p < 0.01) in the radial artery and 0.60 (p < 0.01) in the femoral artery.
  
  
  
  The ProAQT® system can be of additional value if the clinician wants to determine fluid responsiveness in cardiac surgery patients. However, the ProAQT® system provided inaccurate CO measurements compared to transpulmonary thermodilution. The trending ability was poor for COpR but moderate for COpF. Auto-calibration of the system did not improve accuracy of CO measurements nor did it improve the prediction of fluid responsiveness. However, the trending ability was improved by auto-calibration, possibly by correcting a drift over a longer time period.
authors.affiliation: Department of Anesthesiology, Erasmus Medical Center, PO Box 2040, 3000 CA, Rotterdam, The Netherlands. annevandrumpt@hotmail.com.
authors.forename: A
authors.identifier: 0000-0003-0478-8889
authors.initials: A
authors.lastname: van Drumpt
authors.affiliation: Department of Intensive Care Adults, Erasmus Medical Center, Rotterdam, The Netherlands.
authors.forename: J
authors.initials: J
authors.lastname: van Bommel
authors.affiliation: Department of Anesthesiology, Erasmus Medical Center, PO Box 2040, 3000 CA, Rotterdam, The Netherlands.
authors.forename: S
authors.initials: S
authors.lastname: Hoeks
authors.affiliation: Department of Anesthesiology, Erasmus Medical Center, PO Box 2040, 3000 CA, Rotterdam, The Netherlands.
authors.forename: F
authors.initials: F
authors.lastname: Grüne
authors.affiliation: Department of Anesthesiology, Erasmus Medical Center, PO Box 2040, 3000 CA, Rotterdam, The Netherlands.
authors.forename: T
authors.initials: T
authors.lastname: Wolvetang
authors.affiliation: Department of Cardiothoracic Surgery, Erasmus Medical Center, Rotterdam, The Netherlands.
authors.forename: J
authors.initials: J
authors.lastname: Bekkers
authors.affiliation: Department of Anesthesiology, Erasmus Medical Center, PO Box 2040, 3000 CA, Rotterdam, The Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: Ter Horst
mesh_terms: D000368:Aged; D001794:Blood Pressure / Q000502:physiology; D002302:Cardiac Output / Q000502:physiology*; D006348:Cardiac Surgical Procedures; D057785:Catheters; D005260:Female; D005263:Femoral Artery / Q000502:physiology*; D006801:Humans; D008297:Male; D016343:Monitoring, Intraoperative / Q000295:instrumentation*; D011446:Prospective Studies; D017534:Radial Artery / Q000502:physiology*; D013815:Thermodilution
keywords: Agreement; Cardiac output; Fluid responsiveness; Pulse contour analysis; Transpulmonary thermodilution; Trending ability