title: Comparison of ECG-based physiological markers for hypoxia in a preterm ovine model.
abstract: Current methods for assessing perinatal hypoxic conditions did not improve infant outcomes. Various waveform-based and interval-based ECG markers have been suggested, but not directly compared. We compare performance of ECG markers in a standardized ovine model for fetal hypoxia.
  
  
  
  Sixty-nine fetal sheep of 0.7 gestation had ECG recorded 4 h before, during, and 4 h after a 25-min period of umbilical cord occlusion (UCO), leading to severe hypoxia. Various ECG markers were calculated, among which were heart rate (HR), HR-corrected ventricular depolarization/repolarization interval (QTc), and ST-segment analysis (STAN) episodic and baseline rise markers, analogue to clinical STAN device alarms. Performance of interval- and waveform-based ECG markers was assessed by correlating predicted and actual hypoxic/normoxic state.
  
  
  
  Of the markers studied, HR and QTc demonstrated high sensitivity (≥86%), specificity (≥96%), and positive predictive value (PPV) (≥86%) and detected hypoxia in ≥90% of fetuses at 4 min after UCO. In contrast, STAN episodic and baseline rise markers displayed low sensitivity (≤20%) and could not detect severe fetal hypoxia in 65 and 28% of the animals, respectively.
  
  
  
  Interval-based HR and QTc markers could assess the presence of severe hypoxia. Waveform-based STAN episodic and baseline rise markers were ineffective as markers for hypoxia.
authors: Department of Biomedical Engineering, Maastricht University, Maastricht, The Netherlands.|MHeNs School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands.|CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands.
authors: Alex
authors: 0000-0002-0342-9545
authors: A
authors: Zwanenburg
authors: Department of Biomedical Engineering, Maastricht University, Maastricht, The Netherlands.|Department of Technical Medicine, University of Twente, Enschede, The Netherlands.
authors: Ben Jm
authors: BJ
authors: Hermans
authors: Department of Pediatrics, Maastricht University Medical Centre, Maastricht, The Netherlands.|Department of Pediatrics, Máxima Medical Centre, Veldhoven, The Netherlands.
authors: Peter
authors: P
authors: Andriessen
authors: Department of Pediatrics, Maastricht University Medical Centre, Maastricht, The Netherlands.
authors: Hendrik J
authors: HJ
authors: Niemarkt
authors: Department of Pediatrics, Maastricht University Medical Centre, Maastricht, The Netherlands.
authors: Reint K
authors: RK
authors: Jellema
authors: MHeNs School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands.|Department of Pediatrics, Maastricht University Medical Centre, Maastricht, The Netherlands.
authors: Daan Rmg
authors: DR
authors: Ophelders
authors: Signal Processing Systems Group, Department of Electrical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands.
authors: Rik
authors: R
authors: Vullings
authors: MHeNs School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands.|Department of Pediatrics, Maastricht University Medical Centre, Maastricht, The Netherlands.|GROW School for Oncology and Developmental Biology, Maastricht University, Maastricht, The Netherlands.
authors: Tim Gam
authors: TG
authors: Wolfs
authors: MHeNs School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands.|Department of Pediatrics, Maastricht University Medical Centre, Maastricht, The Netherlands.|GROW School for Oncology and Developmental Biology, Maastricht University, Maastricht, The Netherlands.
authors: Boris W
authors: BW
authors: Kramer
authors: Department of Biomedical Engineering, Maastricht University, Maastricht, The Netherlands.|CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands.
authors: Tammo
authors: 0000-0001-6897-9700
authors: T
authors: Delhaas
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D004195:Disease Models, Animal; D004562:Electrocardiography; D005260:Female; D006339:Heart Rate; D006863:Hydrogen-Ion Concentration; D000860:Hypoxia / Q000175:diagnosis*; D007511:Ischemia / Q000175:diagnosis*; D008297:Male; D012372:ROC Curve; D012680:Sensitivity and Specificity; D012756:Sheep; D013997:Time Factors