The value of ETCO2 measurement for COPD patients in the emergency department

We aimed to determine the value of sidestream end-tidal carbon dioxide (SS-ETCO2) measurement in patients with chronic obstructive pulmonary disease (COPD) in the emergency department. Cross-sectional associations between ETCO2 and PaCO2 were examined in the study. This prospective cross-sectional study has been carried out over a 3-month period in a tertiary care university hospital emergency department with an annual census of 75 000 visits. During the study period, simultaneous SS-ETCO2 measurement using a Medlab Cap 10 sidestream capnograph was performed on every COPD patient requiring arterial blood gas analysis. The demographics, diagnosis, vital signs, laboratory test results and clinical outcomes of the patients were recorded. SS-ETCO2 measurement and arterial blood gas analysis were carried out on 118 patients. Mean arterial PCO2 levels were 43.24±14.73 and mean ETCO2 levels were 34.23±10.86 mmHg. Agreement between PCO2 and ETCO2 measurements was 8.4 mmHg and a precision of 11.1 mmHg. As there is only a moderate correlation between PCO2 and ETCO2 levels in COPD patients, ETCO2 measurement should not be considered as a part of the decision-making process to predict PaCO2 level in COPD patients.

[1]  D. Gollman,et al.  Relationship between Arterial and Peak Expired Carbon Dioxide Pressure during Anesthesia and Factors Influencing the Difference , 1981, Anesthesia and analgesia.

[2]  D. Sue,et al.  Pulse oximetry and capnography in intensive and transitional care units. , 1992, The Western journal of medicine.

[3]  C. Barton,et al.  Correlation of end-tidal CO2 measurements to arterial PaCO2 in nonintubated patients. , 1994, Annals of emergency medicine.

[4]  M. Engoren,et al.  Evaluation of capnography in nonintubated emergency department patients with respiratory distress. , 1995, Academic emergency medicine : official journal of the Society for Academic Emergency Medicine.

[5]  M. Tessler,et al.  Misleading end-tidal CO2 tensions , 1996, Canadian journal of anaesthesia = Journal canadien d'anesthesie.

[6]  S. Grmec.  Comparison of three different methods to confirm tracheal tube placement in emergency intubation , 2002, Intensive Care Medicine.

[7]  G. Gaddis,et al.  Arterial blood gas results rarely influence emergency physician management of patients with suspected diabetic ketoacidosis. , 2003, Academic emergency medicine : official journal of the Society for Academic Emergency Medicine.

[8]  C. Yosefy,et al.  End tidal carbon dioxide as a predictor of the arterial Pco2 in the emergency department setting , 2004, Emergency Medicine Journal.

[9]  D. Hess,et al.  Principles & guidelines for respiratory monitoring on the general care floor , 1996, Journal of Clinical Monitoring.

[10]  P. Bijur,et al.  Concordance between capnography and arterial blood gas measurements of carbon dioxide in acute asthma. , 2005, Annals of emergency medicine.

[11]  B. Krauss,et al.  End-Tidal Carbon Dioxide as a Measure of Acidosis Among Children With Gastroenteritis , 2006, Pediatrics.

[12]  M. Agus,et al.  Continuous non‐invasive end‐tidal CO2 monitoring in pediatric inpatients with diabetic ketoacidosis , 2006, Pediatric diabetes.

[13]  M. Zonfrillo,et al.  Quantitative end-tidal carbon dioxide in acute exacerbations of asthma. , 2008, The Journal of pediatrics.

[14]  M. Agus,et al.  The correlation and level of agreement between end-tidal and blood gas pCO2 in children with respiratory distress: a retrospective analysis , 2009, BMC pediatrics.

[15]  B. Krauss,et al.  Capnographic Monitoring in Respiratory Emergencies , 2009 .