title: Carbon dioxide monitoring during long-term noninvasive respiratory support in children.
abstract: BACKGROUND
  Routine monitoring of noninvasive respiratory support relies on nocturnal pulse oximetry and daytime arterial blood gases, without systematic nocturnal carbon dioxide recording. The aim of the study was to assess if overnight pulse oximetry and daytime blood gases are sufficiently accurate to detect nocturnal hypoventilation in children receiving long-term noninvasive respiratory support.
  
  
  METHODS
  Pulse oximetry and carbon dioxide pressure measured by capillary arterialized blood gases and a combined transcutaneous carbon dioxide and pulse oximetry (PtcCO(2)/SpO(2)) monitor were compared in 65 patients (asthma, n = 16, recurrent bronchitis, n = 8, lung infection, n = 8, cystic fibrosis, n = 15, interstitial lung disease, n = 6, neuromuscular disease, n = 12). Daytime capillary arterialized blood gases and nocturnal recording of pulse oximetry and carbon dioxide by means of a combined PtcCO(2)/SpO(2) monitor were performed in 50 other patients receiving nocturnal noninvasive respiratory support at home.
  
  
  RESULTS
  A correlation was observed between pulse oximetry (r = 0.832, P < 0.0001) and carbon dioxide pressure (r = 0.644, P < 0.0001) measured by capillary arterialized blood gases and the combined PtcCO(2)/SpO(2) monitor. Twenty-one of the 50 patients (42%) on long-term noninvasive respiratory support presented nocturnal hypercapnia, defined by a PtcCO(2) value >50 mmHg, without nocturnal hypoxemia. Daytime capillary arterialized carbon dioxide levels were normal in 18 of these 21 patients.
  
  
  CONCLUSIONS
  Nocturnal hypercapnia may occur in children receiving nocturnal noninvasive respiratory support at home. Nocturnal pulse oximetry and daytime arterial blood gases are not sufficiently accurate to diagnose nocturnal hypercapnia, underlying the importance of a systematic carbon dioxide monitoring in children receiving noninvasive respiratory support.
authors.affiliation: Pediatric Pulmonary Department, Exequiel Gonzalez Cortes Hospital, Santiago, Chili.
authors.forename: Rebeca
authors.initials: R
authors.lastname: Paiva
authors.forename: Uros
authors.initials: U
authors.lastname: Krivec
authors.forename: Guillaume
authors.initials: G
authors.lastname: Aubertin
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Cohen
authors.forename: Annick
authors.initials: A
authors.lastname: Clément
authors.forename: Brigitte
authors.initials: B
authors.lastname: Fauroux
mesh_terms: D000293:Adolescent; D001784:Blood Gas Analysis / Q000379:methods*; D002245:Carbon Dioxide / Q000097:blood*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007040:Hypoventilation / Q000097:blood / Q000175:diagnosis; D007223:Infant; D008297:Male; D010092:Oximetry; D011175:Positive-Pressure Respiration
chemical_list: D002245:Carbon Dioxide