Increasing arterial carbon dioxide tension: Influence on transcutaneous carbon dioxide tension measurements

Academic Article

Abstract

  • Despite widespread use of transcutaneous PCO (TcPCO ) monitoring, the precise relationship between TcPCO and PaCO remains unclear. It has been widely assumed that theoretical correction of TcPCO (combining temperature correction with a constant metabolic factor of 4 mm Hg) accounts for the elevation of TcPCO over PaCO . To test this assumption, TcPCO was measured with a 44°C electrode and compared to PaCO in 60 normotensive infants with cardiorespiratory disease during the first four ± six days of life (mean ± SD) (range one to 36 days). During hypocapnea, theoretically corrected TcPCO did not differ significantly from PaCO . In contrast, during normocapnea, theoretically corrected TcPCO exceeded PaCO by 5 ± 4 mm Hg (P < .001), and similarly during hypercapnea, theoretically corrected TcPCO exceeded PaCO by 9 ± 6 mm Hg (P < .001). These data suggest that, as PaCO increases, there may be an imbalance between tissue CO production and removal, resulting in a progressively increasing gradient between TcPCO and PaCO . Clarification of the relationship between TcPCO and PaCO should enhance the interpretation of TcPCO measurements in infants. 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2
  • Authors

    Published In

  • Pediatrics  Journal
  • Author List

  • Martin RJ; Beoglos A; Miller MJ; DiFiore JM; Robertson SS; Carlo WA
  • Start Page

  • 684
  • End Page

  • 687
  • Volume

  • 81
  • Issue

  • 5