J Korean Soc Emerg Med.  1998 Dec;9(4):578-585.

Correlation Analysis between END-tidal CO2 Tension and Arterial CO2 Tension in Nonintubated Emergency Department Patients with Respiratory Distress

• Kim HK
• Park SH
• Oh DR
• Park KN
• Lee WJ
• Hwang DY
• Choi SP
• Lee WJ
• Jeong SK
• Kim SK

Abstract

BACKGROUND: The end-tidal carbon dioxide tension(ETCO2) is defied as a partial pressure of carbon dioxide at the end of an exhaled breath.)he purpose of this study is to determine the correlation between ETCO2 and arterial carbon dioxide tension(PaO2) in nonintubated abated patients with respiratory distress in emergency department(ED).
METHODS
A prospective non-blind study was performed in ED of our university hospitals. Participants included all nonintubated adult patients with respiratory distress requiring arterial blood gas analysis. ETCO2 was measured with a capnography monitor during tidal volume breathing. ETCO2 were recoreded at the time of arterial blood gas sampling. The correlation between ETCO2 and PaCO2 was analysed in all patients and in subgroups by simple linear regression.
RESULTS
Sixty patients were enrolled. In all patients, ETCO2 was 5.72mmHg lower than PaCO2 and correlated well with PaCO 2(r2=0.716). ETCO2 correlated best with PaCO2) in patients who were either acidotic or non-smoking.
CONCLUSION
ETCO2 correlate well with PaCO2 in nonintubated patients with respiratory distress in ED. ETCO2 may be sufficient to reflect PaCO2 in selected patients and obviate the need far repeat arterial blood gas determination.

MeSH Terms

Adult
Blood Gas Analysis
Capnography
Carbon Dioxide
Emergencies*
Emergency Service, Hospital*
Hospitals, University
Humans
Linear Models
Partial Pressure
Prospective Studies
Respiration
Tidal Volume
Carbon Dioxide