title: Evaluation of the Aesculon cardiac output monitor by subxiphoidal Doppler flow measurement in children with congenital heart defects.
abstract: OBJECTIVE
  To evaluate the noninvasive electrical velocimetry (Aesculon) monitor for cardiac output (CO) by subxiphoidal Doppler flow measurement in children.
  
  
  METHODS
  CO was determined at the end of diagnostic or interventional cardiac catheterization for congenital heart defects. Standard ECG surface electrodes were attached in a vertical direction to the patients' left middle and lower neck, and lower thorax at the level of the heart and xiphoid process. Aesculon CO data were compared with a simultaneously measured CO by the subxiphoidal Doppler flow measurement technique. For each patient, measurements were repeated three times within 5 min. Whitney U-test, simple regression and Bland-Altman analysis were performed to compare CO values obtained by the two techniques. Data are given as range (median).
  
  
  RESULTS
  A total of 36 children aged 5.7 (0.5-16.0) years were investigated. CO values obtained by Aesculon monitor [0.55-5.58 (2.62) l min] and subxiphoidal Doppler flow measurements [0.62-6.27 (3.05) l min] differed significantly between both methods (P = 0.04). Simple regression analysis revealed moderate correlation between CO values obtained from the two techniques (r = 0.5544, P < 0.001). Bias between the two methods was 0.31 l min with a precision of 1.92 l min.
  
  
  CONCLUSIONS
  We conclude that electrical velocimetry using the Aesculon monitor does not reliably reflect absolute CO values as compared with subxiphoidal Doppler flow measurement.
authors.affiliation: Division of Cardiology, University Children's Hospital, Zurich, Switzerland. maren.tomaske@kispi.uzh.ch
authors.forename: Maren
authors.initials: M
authors.lastname: Tomaske
authors.forename: Walter
authors.initials: W
authors.lastname: Knirsch
authors.forename: Oliver
authors.initials: O
authors.lastname: Kretschmar
authors.forename: Christian
authors.initials: C
authors.lastname: Balmer
authors.forename: Katja
authors.initials: K
authors.lastname: Woitzek
authors.forename: Achim
authors.initials: A
authors.lastname: Schmitz
authors.forename: Urs
authors.initials: U
authors.lastname: Bauersfeld
authors.forename: Markus
authors.initials: M
authors.lastname: Weiss
mesh_terms: D000293:Adolescent; D006328:Cardiac Catheterization / Q000379:methods*; D002302:Cardiac Output; D002307:Cardiography, Impedance / Q000379:methods; D002648:Child; D002675:Child, Preschool; D015150:Echocardiography, Doppler / Q000379:methods; D005260:Female; D006330:Heart Defects, Congenital / Q000175:diagnosis / Q000601:surgery*; D006801:Humans; D007223:Infant; D008297:Male; D016343:Monitoring, Intraoperative / Q000379:methods; D012044:Regression Analysis; D015203:Reproducibility of Results; D012212:Rheology; D018709:Statistics, Nonparametric