title: Exhaled CO2 Parameters as a Tool to Assess Ventilation-Perfusion Mismatching during Neonatal Resuscitation in a Swine Model of Neonatal Asphyxia.
abstract: BACKGROUND
  End-tidal CO2 (ETCO2), partial pressure of exhaled CO2 (PECO2), and volume of expired CO2 (VCO2) can be continuously monitored non-invasively to reflect pulmonary ventilation and perfusion status. Although ETCO2 ≥14 mmHg has been shown to be associated with return of an adequate heart rate in neonatal resuscitation and quantifying the PECO2 has the potential to serve as an indicator of resuscitation quality, there is little information regarding capnometric measurement of PECO2 and ETCO2 in detecting return of spontaneous circulation (ROSC) and survivability in asphyxiated neonates receiving cardiopulmonary resuscitation (CPR).
  
  
  METHODS
  Seventeen newborn piglets were anesthetized, intubated, instrumented, and exposed to 45-minute normocapnic hypoxia followed by apnea to induce asphyxia. Protocolized resuscitation was initiated when heart rate decreased to 25% of baseline. Respiratory and hemodynamic parameters including ETCO2, PECO2, VCO2, heart rate, cardiac output, and carotid artery flow were continuously measured and analyzed.
  
  
  RESULTS
  There were no differences in respiratory and hemodynamic parameters between surviving and non-surviving piglets prior to CPR. Surviving piglets had significantly higher ETCO2, PECO2, VCO2, cardiac index, and carotid artery flow values during CPR compared to non-surviving piglets.
  
  
  CONCLUSIONS
  Surviving piglets had significantly better respiratory and hemodynamic parameters during resuscitation compared to non-surviving piglets. In addition to optimizing resuscitation efforts, capnometry can assist by predicting outcomes of newborns requiring chest compressions.
authors.affiliation: Faculty of Science, McGill University, Montreal, Quebec, Canada.|Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Elliott Shang-shun
authors.initials: ES
authors.lastname: Li
authors.affiliation: Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada.|Centre for the Studies of Asphyxia and Resuscitation, Neonatal Research Unit, Royal Alexandra Hospital, Edmonton, Alberta, Canada.|Department of Surgery, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Po-Yin
authors.initials: PY
authors.lastname: Cheung
authors.affiliation: Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada.|Centre for the Studies of Asphyxia and Resuscitation, Neonatal Research Unit, Royal Alexandra Hospital, Edmonton, Alberta, Canada.
authors.forename: Megan
authors.initials: M
authors.lastname: O'Reilly
authors.affiliation: Department of Surgery, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Joseph
authors.initials: J
authors.lastname: LaBossiere
authors.affiliation: Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Tze-Fun
authors.initials: TF
authors.lastname: Lee
authors.affiliation: Centre for the Studies of Asphyxia and Resuscitation, Neonatal Research Unit, Royal Alexandra Hospital, Edmonton, Alberta, Canada.|Faculty of Science, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Shaun
authors.initials: S
authors.lastname: Cowan
authors.affiliation: Department of Surgery, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: David L
authors.initials: DL
authors.lastname: Bigam
authors.affiliation: Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada.|Centre for the Studies of Asphyxia and Resuscitation, Neonatal Research Unit, Royal Alexandra Hospital, Edmonton, Alberta, Canada.
authors.forename: Georg Marcus
authors.initials: GM
authors.lastname: Schmölzer
mesh_terms: D000818:Animals; D001238:Asphyxia Neonatorum / Q000503:physiopathology / Q000628:therapy*; D002245:Carbon Dioxide / Q000378:metabolism; D045853:Exhalation; D006439:Hemodynamics; D012151:Resuscitation / Q000379:methods*; D013552:Swine; D014692:Ventilation-Perfusion Ratio
chemical_list: D002245:Carbon Dioxide