title: Continuous non-invasive finger arterial pressure monitoring reflects intra-arterial pressure changes in children undergoing cardiac surgery.
abstract: BACKGROUND
  Continuous non-invasive measurement of finger arterial pressure (FAP) is a reliable technology in adults. FAP is measured with an inflatable cuff around the finger and simultaneously converted to a reconstructed brachial artery pressure waveform (reBAP) by the Nexfin™ device. We assessed the adequacy of a prototype device (Nexfin-paediatric), designed for a paediatric population, for detecting rapid arterial pressure changes in children during cardiac surgery.
  
  
  METHODS
  Thirteen anaesthetized children with a median age of 11 months (2 months-7 yr) undergoing congenital cardiac surgery were included in the study. reBAP and intra-arterial pressure (IAP) were recorded simultaneously during the surgical procedure. To assess the accuracy of reBAP in tracking arterial pressure changes, the four largest IAP variations within a 5 min time interval were identified from each procedure. These variations were compared offline with reBAP during a 10 s control period before and a 10 s period after an arterial pressure change had occurred.
  
  
  RESULTS
  In 10 out of 13 children, a non-invasive arterial pressure recording could be obtained. Therefore, recordings from these 10 children were eligible for further analysis, resulting in 40 data points. The correlation coefficient between reBAP and IAP in tracking mean arterial pressure (MAP) changes was 0.98. reBAP followed changes in IAP with a mean bias for systolic, diastolic arterial pressure, and MAP of 0.0 mm Hg (sd 5.8), 0.1 (sd 2.8), and 0.19 (sd 2.7), respectively.
  
  
  CONCLUSIONS
  The prototype device closely follows arterial pressure changes in children. However, in a considerable number of attempts, obtaining a signal was time-consuming or unsuccessful. This technique seems promising but requires further technical development.
authors.affiliation: Department of Anaesthesiology, Radboud University Nijmegen Medical Centre, Internal Postal Code 632, PO Box 9101, 6500 HB, Nijmegen, The Netherlands.
authors.forename: C M
authors.initials: CM
authors.lastname: Hofhuizen
authors.forename: J
authors.initials: J
authors.lastname: Lemson
authors.forename: A E A
authors.initials: AE
authors.lastname: Hemelaar
authors.forename: J J
authors.initials: JJ
authors.lastname: Settels
authors.forename: O
authors.initials: O
authors.lastname: Schraa
authors.forename: S K
authors.initials: SK
authors.lastname: Singh
authors.forename: J G
authors.initials: JG
authors.lastname: van der Hoeven
authors.forename: G J
authors.initials: GJ
authors.lastname: Scheffer
mesh_terms: D001794:Blood Pressure; D001795:Blood Pressure Determination / Q000295:instrumentation / Q000379:methods*; D015924:Blood Pressure Monitors; D002648:Child; D002675:Child, Preschool; D005385:Fingers / Q000098:blood supply; D006330:Heart Defects, Congenital / Q000601:surgery*; D006801:Humans; D007223:Infant; D016343:Monitoring, Intraoperative / Q000295:instrumentation / Q000379:methods*; D015203:Reproducibility of Results