Korean J Anesthesiol.  1998 Aug;35(2):321-326. 10.4097/kjae.1998.35.2.321.

Changes in Arterial to End Tidal CO2 Difference during Pediatric Open Heart Surgery: Cyanotic vs Acyanotic Congenital Heart Diseases

• Lee YH
• Cho MW
• Choi IC
• Sim JY

• KMID: 2298949
• DOI: http://doi.org/10.4097/kjae.1998.35.2.321

Abstract

BACKGROUND
The arterial to end-tidal carbon dioxide tension difference(Pa-ETCO2) can be increased in patients with congenital heart disease(CHD) and, therefore, end-tidal carbon dioxide tension(PETCO2) does not accurately approximates arterial carbon dioxide tension(PaCO2). The purpose of this study was to evaluate the stability of the Pa-ETCO2 in pediatric patients with congenital heart disease undergoing open heart surgery.
METHODS
Forty three children with CHD were studied: twenty two were acyanotic and twenty one were cyanotic. Simultaneous PETCO2 and PaCO2 measurements, as well as pulse rate, blood pressure, pH and arterial oxygen tension(PaO2) were obtained for each patient during four intraoperative events: (1) after induction of anesthesia and before sternotomy, (2) after sternotomy and before cardiopulmonary bypass(CPB), (3) after weaning of CPB, and (4) after closure of sternotomy.
RESULTS
The PETCO2 of cyanotic group were lower than that of acyanotic group throughout operation period, and did not change significantly after CPB. Cyanotic children demonstrated a greater Pa-ETCO2 difference before CPB as compared with acyanotic group. In acyanotic group, Pa-ETCO2 difference increased significantly after CPB(P <0.05), whereas it remained unchanged in cyanotic group.
CONCLUSIONS
Since cyanotic children had higher Pa-ETCO2 differences intraoperatively and acyanotic children showed an increase in Pa-ETCO2 after CPB, the PETCO2 cannot be the alternative value to estimate reliably the PaCO2 during open heart surgery of pediatric CHD.

Keyword

Anesthesia: cardiovascular; pediatric; Carbon dioxide: tension; end-tidal, arterial; Heart: congenital defects; Monitoring: blood gas; capnography

MeSH Terms

Anesthesia
Blood Pressure
Carbon Dioxide
Child
Heart Defects, Congenital
Heart Diseases*
Heart Rate
Heart*
Humans
Hydrogen-Ion Concentration
Oxygen
Sternotomy
Thoracic Surgery*
Weaning
Carbon Dioxide
Oxygen