Background: This prospective observational study compared endtidal carbon dioxide (PECO2) with blood gas carbon dioxide (PaCO 2) values in children sedated by nonanesthesiologists for cardiac catheterization. Methods: A nasal cannula designed to obtain gas sampling simultaneously from over the mouth and nares was taped into place after assuring a good waveform. Patients' cardiac lesions, site of blood gas sampling and PECO2 were recorded. Results: Two hundred and one blood/PECO2 pairs were measured in 59 patients from 4 days to 18 years of age. Linear regression, Pearson correlation, and Bland-Altman analysis revealed a reasonable relationship (r = 0.493, P < 0.01, bivariate Pearson correlation) for all blood/expired CO2 pairs even when the blood sample was obtained from an area of the circulation with shunting. There was no significant difference in the accuracy of the blood/PECO 2 pairs between infants who weighed ≤15 kg compared with children who weighed >15 kg. Thirteen children were diagnosed with partial or complete airway obstruction. Conclusions: Endtidal CO2 measurement provides a reasonable reflection of blood CO2 values if the expired gas-sampling catheter is taped in place after assuring a good waveform. The veracity of the data was the same throughout the patient size range. Expired CO2 monitoring is useful for assessing the adequacy of respirations and the patency of the airway in children 3-89 kg.
- Blood gases
- Expired carbon dioxide
ASJC Scopus subject areas
- Anesthesiology and Pain Medicine
- Pediatrics, Perinatology, and Child Health