OBJECTIVES: The purpose of this study is to examine the relation between end-tidal carbon dioxide (ETCO₂) measurement and bicarbonate (HCO₃) level reflecting the patient's metabolic status. METHOD: This prospective cross-sectional study has been carried out during a 3-month period in a tertiary care university hospital's emergency department (ED). During the study period, every spontaneously ventilating ED patient requiring arterial blood gas analysis for any medical indication, regardless of presenting symptoms, had a simultaneous ETCO₂ measurement using a Medlab Cap 10 side stream capnograph. The demographics and clinical outcomes of the patients were recorded. RESULTS: Of 399 eligible patients, 240 with possible metabolic disturbance were enrolled into the study. There was a statistically significant correlation between the value of ETCO₂ and HCO₃ levels (r = 0.506). The mean ET(CO)₂ level was statistically significantly lower in patients who died (26.5 ± 7.2, 95% confidence interval [CI], 24.2-28.6, vs 30 ± 7.5, 95% CI, 29-31; P = .007) and who had low bicarbonate levels (25.7 ± 6.7, 95% CI, 24.3-27.1, vs 31.6 ± 7.1, 95% CI, 30.4-32.8; P = .000). The value of ET(CO)₂ measurement to detect low bicarbonate level was found to be significant. The area under the receiver operating characteristic curve was 0.734, the (+) likelihood ratio for ETCO₂ less than or equal to 25 was 2.7, and the (-) likelihood ratio for ETCO₂ greater than or equal to 36 was 0.05. CONCLUSION: ETCO₂ values correlate moderately with HCO₃ levels and thus might predict mortality and metabolic acidosis. Therefore, side stream capnograph can be used as a noninvasive diagnostic tool for ruling out suspected severe metabolic disturbance in the ED.
OBJECTIVES: The purpose of this study is to examine the relation between end-tidal carbon dioxide (ETCO₂) measurement and bicarbonate (HCO₃) level reflecting the patient's metabolic status. METHOD: This prospective cross-sectional study has been carried out during a 3-month period in a tertiary care university hospital's emergency department (ED). During the study period, every spontaneously ventilating ED patient requiring arterial blood gas analysis for any medical indication, regardless of presenting symptoms, had a simultaneous ETCO₂ measurement using a Medlab Cap 10 side stream capnograph. The demographics and clinical outcomes of the patients were recorded. RESULTS: Of 399 eligible patients, 240 with possible metabolic disturbance were enrolled into the study. There was a statistically significant correlation between the value of ETCO₂ and HCO₃ levels (r = 0.506). The mean ET(CO)₂ level was statistically significantly lower in patients who died (26.5 ± 7.2, 95% confidence interval [CI], 24.2-28.6, vs 30 ± 7.5, 95% CI, 29-31; P = .007) and who had low bicarbonate levels (25.7 ± 6.7, 95% CI, 24.3-27.1, vs 31.6 ± 7.1, 95% CI, 30.4-32.8; P = .000). The value of ET(CO)₂ measurement to detect low bicarbonate level was found to be significant. The area under the receiver operating characteristic curve was 0.734, the (+) likelihood ratio for ETCO₂ less than or equal to 25 was 2.7, and the (-) likelihood ratio for ETCO₂ greater than or equal to 36 was 0.05. CONCLUSION: ETCO₂ values correlate moderately with HCO₃ levels and thus might predict mortality and metabolic acidosis. Therefore, side stream capnograph can be used as a noninvasive diagnostic tool for ruling out suspected severe metabolic disturbance in the ED.
Authors: María M Adeva-Andany; Natalia Carneiro-Freire; Cristóbal Donapetry-García; Eva Rañal-Muíño; Yosua López-Pereiro Journal: Biomed Res Int Date: 2014-04-30 Impact factor: 3.411
Authors: Mitchell Barneck; Linda Papa; Ashley Cozart; Kain Lentine; Jay Ladde; Linh Nguyen; Jeremy Mayfield; Josef Thundiyil Journal: J Am Coll Emerg Physicians Open Date: 2021-07-17