title: Measuring cardiac changes using electrical impedance during delayed cord clamping: a feasibility trial.
abstract: BACKGROUND
  To date no study has attempted to continuously evaluate changes in hemodynamics during delayed cord clamping in humans. We aimed to demonstrate 1. the feasibility of measurements of hemodynamics during delayed cord clamping and 2. to describe the changes that occur over each minute.
  
  
  RESULTS
  After vaginal delivery, term infants (37(0)-41(6) weeks) were placed on a Life Start® bed 10-20 cm below the placenta. Transcutaneous sensors were placed on the neck and chest to determine heart rate, stroke volume and cardiac output at each beat. Once a signal was obtained, first 5 values (taken every beat) were averaged and the percent change for each subject from baseline was calculated. 20 infants were enrolled and all had a reliable signal obtained from transcutaneous sensors and had a delay in cord clamping for about 5 minutes. Cardiac output increased from 2 to 5 minutes of life (p = 0.008). For every minute of life the cord was kept unclamped, the stroke volume increased 13.1% ± 12.3 (p = 0.0001) and cardiac output increased 12.6% ± 6.3 from baseline (p < 0.0001). While the majority of infants continued to have an increase in cardiac output at 5 minutes of life, 7/20 infants reached their peak cardiac output at 188 ± 41 seconds of life.
  
  
  CONCLUSIONS
  This study demonstrates that hemodynamic measures could be successfully obtained during the first five minutes of birth and while a newborn was receiving delayed cord clamping. This study also provides reference values for changes in cardiac output and stroke volume in well term infants during delayed cord clamping.
  
  
  BACKGROUND
  Clinical Trials.gov NCT02195037 Registered 17 July 2014.
authors.affiliation: Neonatal Research Institute, Sharp Mary Birch Hospital for Women and Newborns, 3003 Health Center Drive, San Diego, CA 92123 USA.
authors.forename: Anup C
authors.initials: AC
authors.lastname: Katheria
authors.affiliation: Neonatal Research Institute, Sharp Mary Birch Hospital for Women and Newborns, 3003 Health Center Drive, San Diego, CA 92123 USA.
authors.forename: Madeline
authors.initials: M
authors.lastname: Wozniak
authors.affiliation: Sharp Rees-Stealy Medical Group, San Diego, CA USA.
authors.forename: David
authors.initials: D
authors.lastname: Harari
authors.affiliation: Neonatal Research Institute, Sharp Mary Birch Hospital for Women and Newborns, 3003 Health Center Drive, San Diego, CA 92123 USA.
authors.forename: Kathy
authors.initials: K
authors.lastname: Arnell
authors.affiliation: Neonatal Research Institute, Sharp Mary Birch Hospital for Women and Newborns, 3003 Health Center Drive, San Diego, CA 92123 USA.
authors.forename: Deborah
authors.initials: D
authors.lastname: Petruzzelli
authors.affiliation: Neonatal Research Institute, Sharp Mary Birch Hospital for Women and Newborns, 3003 Health Center Drive, San Diego, CA 92123 USA.
authors.forename: Neil N
authors.initials: NN
authors.lastname: Finer
keywords: Cardiac output; Delayed cord clamping; Hemodynamics; Transitional circulation