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End Tidal Capnography in the Emergency Department

Emergency Medicine. 2018 November;50(11):1-9 | 10.12788/emed.2018.0111

Author(s):

Aaron Surrey, MD

Alexandra Lambert, DO, MPH

David Evans, MD, FACEP

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References

Manifold CA, Davids B, Villers LC, Wampler DA. Capnography for the nonintubated patient in the emergency setting. J Emerg Med. 2013;45(4):626-632.
Ward K, Yealy DM. End-tidal carbon dioxide monitoring in emergency medicine, part 1: basic principles. Acad Emerg Med. 1998;5(6):628-636.
Krauss B, Falk JL. Carbon dioxide monitoring (capnography). UpToDate. Waltham MA: UpToDate Inc. www.uptodate.com.
Long B, Koyfman A, Michael AV. Capnography in the emergency department: a review of uses, waveforms, and limitations. J Emerg Med. 2017;(53)6:829-842.
Shankar Kodali B. Capnography: A Comprehensive Educational Website. Boston, MA. www.capnography.com.
Kodali B. Capnography outside the operating room. Anesthesiology. 2013;118:192-201.
Bhavani, S. Defining segments and phases of a time capnogram. Anesth Analg. 2000;91(4):973-977.
Petersson J, Glenny R. Gas exchange and ventilation-perfusion relationships in the lung. Eur Resp J. 2014;44(4):1023-1041.
Nassar B, Schmidt GA. Capnography during critical illness. Chest. 2016;149(2):576-585.
Neumar RW, Otto CW, Link MS, et al. Part 8: Adult advanced cardiovascular life support: 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation. 2010;122(18 suppl 3):S729-S767.
Burns SM, Carpenter R, Blevins C, Bragg S, Marshall M, Browne L, et al. Detection of inadvertent airway intubation during gastric tube insertion: capnography versus a colorimetric carbon dioxide detector. Am J Crit Care. 2006:15(2):188-195.
Goldberg JS, Rawle PR, Zehnder JL, Sladen RN. Colorimetric end-tidal carbon dioxide monitoring for tracheal intubation. Anesthesia and analgesia. 1990:70(2):191-194.
O'Flaherty D, Adams AP. The end-tidal carbon dioxide detector: assessment of a new method to distinguish oesophageal from tracheal intubation. Anaesthesia. 1990:45(8):653-655.
Garnett AR, Ornato JP, Gonzalez ER, Johnson EB. End-tidal carbon dioxide monitoring during cardiopulmonary resuscitation. JAMA. 1987;257:512-515.
Falk JL, Rackow EC, Weil MH. End-tidal carbon dioxide concentration during cardiopulmonary resuscitation. N Engl J Med. 1988;318(10):607-611.
Sheak KR, Wiebe DJ, Leary M, Babaeizadeh S, Yuen TC, Zive D, et al. Quantitative relationship between end-tidal carbon dioxide and CPR quality during both in-hospital and out-of-hospital cardiac arrest. Resuscitation. 2015;89:149-154.
Levine RL, Wayne MA, Miller CC. End-tidal carbon dioxide and outcome of out-of-hospital cardiac arrest. N Engl J Med. 1997;337(5):301-306.
Touma O, Davies M. The prognostic value of end tidal carbon dioxide during cardiac arrest: a systematic review. Resuscitation. 2013;84(11):1470-1479.
Chen JJ, Lee YK, Hou SW, et al. End-tidal carbon dioxide monitoring may be associated with a higher possibility of return of spontaneous circulation during out-of-hospital cardiac arrest: a population-based study. Scan J Trauma Resusc Emerg Med. 2015;23:104.
Neumar RW, Shuster M, Callaway CW et al. Part 7: Executive Summary: 2015 American Heart Association Guidelines Update for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation. 2015;132(suppl 2):S315-S367.
Hartmann SW, Farris RW, Di Gennaro JL, Roberts JS. Systematic review and meta-analysis of end-tidal carbon dioxide values associated with return of spontaneous circulation during cardiopulmonary resuscitation. J Intensive Care Med. 2015;(30):426-435.
Eckstein, M, Hatch, L, Malleck, J et al. EtCO2 as a predictor of survival in out-of hospital cardiac arrest. Prehosp Disaster Med. 2016;104:53-58.
Lui CT, Poon KM, Tsui KL. Abrupt rise of end tidal carbon dioxide was a specific but non-sensitive marker of return of spontaneous circulation with out-of-hospital cardiac arrest. Resuscitation. 2016;104:53-58.
Pokorna M, Necas E, Kratochvil J et al. A sudden increase in partial pressure end-tidal carbon dioxide at the moment of return of spontaneous circulation. J Emerg Med. 2010;38:614-621.
Sanders A, Kern K, Otto C, et al. End-tidal carbon dixoide monitoring during cardiopulmonary resuscitation: a prognostic indicator for survival. JAMA. 1989;262:1347-1351.
Wayne M, Levine R, And Miller C. Use of end-tidal carbon dioxide to predict outcome in prehospital cardiac arrest. Ann Emerg Med. 1995;25(6):762-767.
Poon KM, Lui CT, Tsui KL. Prognostication of out-of-hopsital cardiac arrest patients by 3-min end-tidal capnometry level in emergency department. Resuscitation. 2016;102:80-84.
Einav S, Bromiker R, Weiniger C, Matot I. Mathematical modeling for prediction of survival from resuscitation based on computerized continuous capnography: proof of concept. Acad Emerg Med. 2011;18:468-475.
Pearce A, Davis D, Minokadeh A, Sell R. Initial end-tidal carbon dioxide as a prognostic indicator for inpatient PEA arrest. Resuscitation. 2015;92:77-81.
Akinci, E, Ramadan H, Yuzbasioglu Y, Coksun F. Comparison of end-tidal carbon dioxide levels with cardiopulmonary resuscitation success presented to emergency department with cardiopulmonary arrest. Pak J Med Sci. 2014;30(1):16-21.
Callaham M, Barton C, Matthay M. Effect of epinephrine on the ability of end-tidal carbon dioxide readings to predict initial resuscitation from cardiac arrest. Crit Care Med. 1992; 20:337-343.
Wall BF, Magee K, Campbell SG, Zed PJ. Capnography versus standard monitoring for emergency department procedural sedation and analgesia. Cochrane Database of Systematic Reviews. 2017(3).
Langhan ML, Shabanova V, Li FY, Bernstein SL, Shapiro ED. A randomized controlled trial of capnography during sedation in a pediatric emergency setting. Am J Emerg Med. 2015;33(1):25-30.
Campbell SG, Magee KD, Zed PJ, Froese P, Etsell G, LaPierre A et al. End-tidal capnometry during emergency department procedural sedation and analgesia: a randomized, controlled study. World J Emerg Med. 2016;7(1):13.
Waugh JB, Epps CA, Khodneva YA. Capnography enhances surveillance of respiratory events during procedural sedation: a meta-analysis. J Clin Anesth. 2011;23(3):189-196.
Krauss B, Hess DR. Capnography for procedural sedation and analgesia in the emergency department. Ann Emerg Med. 2007;50(2):172-181.
Deitch K, Miner J, Chudnofsky CR, Dominici P, Latta D. Does end tidal CO2 monitoring during emergency department procedural sedation and analgesia with propofol decrease the incidence of hypoxic events? A randomized, controlled trial. Ann Emerg Med. 2010;55(3):258-264.
Godwin SA, Caro DA, Wolf SJ, Jagoda AS, Charles R, Marett BE, Moore J. Clinical policy: procedural sedation and analgesia in the emergency department. Ann Emerg Med. 2005;45(2):177-196.
Hamber EA, Bailey PI, James SW et al. Delays in the detection of hypoxemia due to site of pulse oximetry pulse placement. J Clin Anesth. 1999;11:113-118.
Mieloszyk RJ, Vergehese GC, Deitch K, et al. Automated quantitative analysis of capnogram shape for COPD-normal and COPD-CHF classification. IEEE Trans Biomed Eng. 2014;61:2882-2890.
Howe TA, Jaalam K, R. Ahmad, Sheng CK, Ab Rahman NHN. The use of end-tidal capnography to monitor non-intubated patients presenting with acute exacerbation of asthma in the emergency department. J Emerg Med. 2011:41:581-589.
Nagurka R, Bechmann S, Gluckman W et al. Utility of initial prehospital end-tidal carbon dioxide measurements to predict poor outcomes in adult asthmatic patients. Prehospital Emerg Care. 2014;18:180-184.
Doğan NÖ, Şener A, Günaydın GP, İçme F, Çelik GK, Kavaklı HŞ, Temrel TA. The accuracy of mainstream end-tidal carbon dioxide levels to predict the severity of chronic obstructive pulmonary disease exacerbations presented to the ED. Am J Emerg Med. 2014;32(5):408-411.
Cinar O, Acar YA, Arziman I, et al. Can mainstream end-tidal carbon dioxide measurement accurately predict the arterial carbon dioxide levels of patients with acute dyspnea in ED. Am J Emerg Med. 2012;30:358-361.
Nassar BS, Schmidt GA. Capnography during critical illness. Chest. 2016:149(2):576-585.
Caputo ND, Fraser RM, Paliga A et al. Nasal cannula end-tidal CO2 correlates with serum lactate levels and odds of operative intervention in penetrating trauma patients: a prospective cohort study. J Trauma Acute Care Surg. 2012;73:1202-1207.
Hunter CL, Silvestri S, Ralls G, Bright S, Papa L. The sixth vital sign: prehospital end-tidal carbon dioxide predicts in-hospital mortality and metabolic disturbances. Am J Emerg Med. 2014;32(2):160-165.
Hunter CL, Silvestri S, Dean M, Falk JL, Papa L. End-tidal carbon dioxide is associated with mortality and lactate in patients with suspected sepsis. Am J Emerg Med. 2013;31(1):64-71.
McGillicuddy DC, Tang A, Cataldo L, et al. Evaluation of end-tidal carbon dioxide role in predicting elevated SOFA and lactic acidosis. Intern Emerg Med. 2009;4:41-44.
Shapiro NI, Howell MD, Talmor D, Nathanson LA, Lisbon A, Wolfe RE, et al. Serum lactate as a predictor of mortality in emergency department patients with infection. Ann Emerg Med. 2005;45:524-528.
Levy, MM, Evans LE, Rhodes A. The surviving sepsis campaign bundle: 2018 update. Crit Care Med. 2018;46:997-1000.
Hunter CL, Silvestri S, Ralls G et al. A prehospital screening tool utilizing end-tidal carbon dioxide predicts sepsis and severe sepsis. Am J Emerg Med. 2016;34:813-819.
Guirgis FW, Williams DJ, Kalynych CJ, Hardy ME, Jones AE, Dodani S, Wears RL. End-tidal carbon dioxide as a goal of early sepsis therapy. Am J Emerg Med. 2014;32(11):1351-1356.
Kartal M, Eray O, Rinnert S, Gosku E, Bektas F, Eken C. ETCO2: a predictive tool for excluding metabolic disturbances in nonintubated patients. Am J Emerg Med. 2011;29: 65-69.
Solmeinpur H, Taghizadieh A, Niafar M, Rahmani F, Golzari SE, Esfanjani RM. Predictive value of capnography for diagnosis in patients with suspected diabetic ketoacidosis in the emergency department. West J Emerg Med. 2013;14:590-594.
Bou Chebl R, Madden B, Belsky J, Harmouche E, Yessayan L. Diagnostic value of end tidal capnography in patients with hyperglycemia in the emergency department. BMC Emerg Med. 2016;16:7.
Fearon DM, Steele DW. End-tidal carbon dioxide predicts the presence and severity of acidosis in children with diabetes. Acad Emerg Med. 2002;9:1373-1378.
Gilhotra Y, Porter P. Predicting diabetic ketoacidosis in children by measuring end-tidal CO2 via non-invasive nasal capnography. J Paediatr Child Health. 2007;43:677-680.
Dunham CM, Chirichella TJ, Gruber BS, et al. In emergently ventilated trauma patients, low end-tidal CO2 and low cardiac output are associated and correlate with hemodynamic instability, hemorrhage, abnormal pupils, and death. BMC Anesthesiol. 2013;13-20.
Deakin CD, Sado DM, Coats TJ, Davies G. Prehospital end-tidal carbon dioxide concentration and outcome in major trauma. J Trauma.2004;57:65-68.
Williams DJ, Guirgis FW, Morrissey TK, Wilkerson J, Wears RL, Kalynych C, Kerwin AJ, Godwin SA. End-tidal carbon dioxide and occult injury in trauma patients: ETCO2 does not rule out severe injury. Am J Emerg Med. 2016;34(11):2146-2149.
Manara A, D’hoore W, Thys F. Capnography as a diagnostic tool for pulmonary embolism: a meta-analysis. Ann Emerg Med. 2013;52:584-591.
Yoon YH, Lee SW, Jung DM et al. The additional use of end-tidal alveolar dead space fraction following D-dimer test to improve diagnostic accuracy for pulmonary embolism in the emergency department. Emerg Med J. 2010;27:663-667.
Hemnes AR, Newman AL, Rosenbaum B, et al. Bedside end-tidal CO2 tension as a screening tool to exclude pulmonary embolism. Eur Resp J. 2010;35:735-741.
Rias I Jacob B. Pulmonary embolism in Bradford, UK: role of end-tidal CO2 as a screening tool. Clin Med (Lond). 2014;14:128-133.
Yuksel M, Pekdemir M, Yilmaz S, et al. Diagnostic accuracy of noninvasive end-tidal carbon dioxide measurement in emergency department patients with suspected pulmonary embolism. Turk J Med Sci. 2016;46:84–90.
Williams D, Morrissey T, Caro D, Wears R, Kalynyc C. Side-stream qunatitative end-tidal carbon dioxide measurement as a triage tool in emergency medicine. Ann Emerg Med. 2011;58:S212-S213.

Capnography is the measurement of the partial pressure of carbon dioxide (CO₂) in exhaled air.¹ It provides real-time information on ventilation (elimination of CO₂), perfusion (CO₂ transportation in vasculature), and metabolism (production of CO₂ via cellular metabolism).² The technology was originally developed in the 1970s to monitor general anesthesia patients; however, its reach has since broadened, with numerous applications currently in use and in development for the emergency provider (EP).³

Capnography exists in two configurations: a mainstream device that attaches directly to the hub of an endotracheal tube (ETT) and a side-stream device that measure levels via nasal or nasal-oral cannula.^1,3

Qualitative monitors use a colorimetric device that monitors the end-tidal CO₂ (EtCO₂) in exhaled gas and changes color depending on the amount of CO₂ present.^2,4 Expired CO₂ and H₂0 form carbonic acid, causing the specially treated litmus paper inside the device to change from purple to yellow.^2,4 Quantitative monitors display a capnogram, the waveform of expired CO₂ as a function of time; as well as the capnometer, which depicts the numerical EtCO₂ for each breath.⁴ In this overview, we will discuss the general interpretation of capnography and its specific uses in the ED.

The Capnogram

Just like the various stages of an electrocardiogram represent different phases of the cardiac cycle, different phases of a capnogram correspond to different phases of the respiratory cycle. Knowing how to analyze and interpret each phase will contribute to the utility of capnography. While there has been considerable ambiguity in the terminology related to the capnogram,^5-7 the most frequently referenced capnogram terminology consists of the following phases (Figure 1):

Phase I: represents beginning of exhalation, where the dead space is cleared from the upper airway.² This should be zero unless the patient is rebreathing CO₂-laden expired gas from either artificially increased dead space or hypoventilation.^2,8 A precipitous rise in both the baseline and EtCO₂ may indicate contamination of the sensor, such as with secretions or water vapor.^2,6

Phase II: rapid rise in exhaled as the CO₂ from the alveoli reaches the sensor.⁴ This rise should be steep, particularly when ventilation to perfusion (V/Q) is well matched. More V/Q heterogeneity, such as with COPD or asthma, leads to a more gradual slope.⁹ A more gradual phase 2 slope may also indicate a delay in CO₂ delivery to the sampling site, such as with bronchospasm or ETT kinking.²

Phase III: the expiratory plateau, which represents the CO₂ concentration approaching equilibrium from alveoli to nose. The plateau should be nearly horizontal.² If all alveoli had the same pCO₂, this plateau would be perfectly flat, but spatial and temporal mismatch in alveolar V/Q ratios result in variable exhaled CO₂. When there is substantial V/Q heterogeneity, the slope of the plateau will increase.^1,2,6

References

Manifold CA, Davids B, Villers LC, Wampler DA. Capnography for the nonintubated patient in the emergency setting. J Emerg Med. 2013;45(4):626-632.
Ward K, Yealy DM. End-tidal carbon dioxide monitoring in emergency medicine, part 1: basic principles. Acad Emerg Med. 1998;5(6):628-636.
Krauss B, Falk JL. Carbon dioxide monitoring (capnography). UpToDate. Waltham MA: UpToDate Inc. www.uptodate.com.
Long B, Koyfman A, Michael AV. Capnography in the emergency department: a review of uses, waveforms, and limitations. J Emerg Med. 2017;(53)6:829-842.
Shankar Kodali B. Capnography: A Comprehensive Educational Website. Boston, MA. www.capnography.com.
Kodali B. Capnography outside the operating room. Anesthesiology. 2013;118:192-201.
Bhavani, S. Defining segments and phases of a time capnogram. Anesth Analg. 2000;91(4):973-977.
Petersson J, Glenny R. Gas exchange and ventilation-perfusion relationships in the lung. Eur Resp J. 2014;44(4):1023-1041.
Nassar B, Schmidt GA. Capnography during critical illness. Chest. 2016;149(2):576-585.
Neumar RW, Otto CW, Link MS, et al. Part 8: Adult advanced cardiovascular life support: 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation. 2010;122(18 suppl 3):S729-S767.
Burns SM, Carpenter R, Blevins C, Bragg S, Marshall M, Browne L, et al. Detection of inadvertent airway intubation during gastric tube insertion: capnography versus a colorimetric carbon dioxide detector. Am J Crit Care. 2006:15(2):188-195.
Goldberg JS, Rawle PR, Zehnder JL, Sladen RN. Colorimetric end-tidal carbon dioxide monitoring for tracheal intubation. Anesthesia and analgesia. 1990:70(2):191-194.
O'Flaherty D, Adams AP. The end-tidal carbon dioxide detector: assessment of a new method to distinguish oesophageal from tracheal intubation. Anaesthesia. 1990:45(8):653-655.
Garnett AR, Ornato JP, Gonzalez ER, Johnson EB. End-tidal carbon dioxide monitoring during cardiopulmonary resuscitation. JAMA. 1987;257:512-515.
Falk JL, Rackow EC, Weil MH. End-tidal carbon dioxide concentration during cardiopulmonary resuscitation. N Engl J Med. 1988;318(10):607-611.
Sheak KR, Wiebe DJ, Leary M, Babaeizadeh S, Yuen TC, Zive D, et al. Quantitative relationship between end-tidal carbon dioxide and CPR quality during both in-hospital and out-of-hospital cardiac arrest. Resuscitation. 2015;89:149-154.
Levine RL, Wayne MA, Miller CC. End-tidal carbon dioxide and outcome of out-of-hospital cardiac arrest. N Engl J Med. 1997;337(5):301-306.
Touma O, Davies M. The prognostic value of end tidal carbon dioxide during cardiac arrest: a systematic review. Resuscitation. 2013;84(11):1470-1479.
Chen JJ, Lee YK, Hou SW, et al. End-tidal carbon dioxide monitoring may be associated with a higher possibility of return of spontaneous circulation during out-of-hospital cardiac arrest: a population-based study. Scan J Trauma Resusc Emerg Med. 2015;23:104.
Neumar RW, Shuster M, Callaway CW et al. Part 7: Executive Summary: 2015 American Heart Association Guidelines Update for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation. 2015;132(suppl 2):S315-S367.
Hartmann SW, Farris RW, Di Gennaro JL, Roberts JS. Systematic review and meta-analysis of end-tidal carbon dioxide values associated with return of spontaneous circulation during cardiopulmonary resuscitation. J Intensive Care Med. 2015;(30):426-435.
Eckstein, M, Hatch, L, Malleck, J et al. EtCO2 as a predictor of survival in out-of hospital cardiac arrest. Prehosp Disaster Med. 2016;104:53-58.
Lui CT, Poon KM, Tsui KL. Abrupt rise of end tidal carbon dioxide was a specific but non-sensitive marker of return of spontaneous circulation with out-of-hospital cardiac arrest. Resuscitation. 2016;104:53-58.
Pokorna M, Necas E, Kratochvil J et al. A sudden increase in partial pressure end-tidal carbon dioxide at the moment of return of spontaneous circulation. J Emerg Med. 2010;38:614-621.
Sanders A, Kern K, Otto C, et al. End-tidal carbon dixoide monitoring during cardiopulmonary resuscitation: a prognostic indicator for survival. JAMA. 1989;262:1347-1351.
Wayne M, Levine R, And Miller C. Use of end-tidal carbon dioxide to predict outcome in prehospital cardiac arrest. Ann Emerg Med. 1995;25(6):762-767.
Poon KM, Lui CT, Tsui KL. Prognostication of out-of-hopsital cardiac arrest patients by 3-min end-tidal capnometry level in emergency department. Resuscitation. 2016;102:80-84.
Einav S, Bromiker R, Weiniger C, Matot I. Mathematical modeling for prediction of survival from resuscitation based on computerized continuous capnography: proof of concept. Acad Emerg Med. 2011;18:468-475.
Pearce A, Davis D, Minokadeh A, Sell R. Initial end-tidal carbon dioxide as a prognostic indicator for inpatient PEA arrest. Resuscitation. 2015;92:77-81.
Akinci, E, Ramadan H, Yuzbasioglu Y, Coksun F. Comparison of end-tidal carbon dioxide levels with cardiopulmonary resuscitation success presented to emergency department with cardiopulmonary arrest. Pak J Med Sci. 2014;30(1):16-21.
Callaham M, Barton C, Matthay M. Effect of epinephrine on the ability of end-tidal carbon dioxide readings to predict initial resuscitation from cardiac arrest. Crit Care Med. 1992; 20:337-343.
Wall BF, Magee K, Campbell SG, Zed PJ. Capnography versus standard monitoring for emergency department procedural sedation and analgesia. Cochrane Database of Systematic Reviews. 2017(3).
Langhan ML, Shabanova V, Li FY, Bernstein SL, Shapiro ED. A randomized controlled trial of capnography during sedation in a pediatric emergency setting. Am J Emerg Med. 2015;33(1):25-30.
Campbell SG, Magee KD, Zed PJ, Froese P, Etsell G, LaPierre A et al. End-tidal capnometry during emergency department procedural sedation and analgesia: a randomized, controlled study. World J Emerg Med. 2016;7(1):13.
Waugh JB, Epps CA, Khodneva YA. Capnography enhances surveillance of respiratory events during procedural sedation: a meta-analysis. J Clin Anesth. 2011;23(3):189-196.
Krauss B, Hess DR. Capnography for procedural sedation and analgesia in the emergency department. Ann Emerg Med. 2007;50(2):172-181.
Deitch K, Miner J, Chudnofsky CR, Dominici P, Latta D. Does end tidal CO2 monitoring during emergency department procedural sedation and analgesia with propofol decrease the incidence of hypoxic events? A randomized, controlled trial. Ann Emerg Med. 2010;55(3):258-264.
Godwin SA, Caro DA, Wolf SJ, Jagoda AS, Charles R, Marett BE, Moore J. Clinical policy: procedural sedation and analgesia in the emergency department. Ann Emerg Med. 2005;45(2):177-196.
Hamber EA, Bailey PI, James SW et al. Delays in the detection of hypoxemia due to site of pulse oximetry pulse placement. J Clin Anesth. 1999;11:113-118.
Mieloszyk RJ, Vergehese GC, Deitch K, et al. Automated quantitative analysis of capnogram shape for COPD-normal and COPD-CHF classification. IEEE Trans Biomed Eng. 2014;61:2882-2890.
Howe TA, Jaalam K, R. Ahmad, Sheng CK, Ab Rahman NHN. The use of end-tidal capnography to monitor non-intubated patients presenting with acute exacerbation of asthma in the emergency department. J Emerg Med. 2011:41:581-589.
Nagurka R, Bechmann S, Gluckman W et al. Utility of initial prehospital end-tidal carbon dioxide measurements to predict poor outcomes in adult asthmatic patients. Prehospital Emerg Care. 2014;18:180-184.
Doğan NÖ, Şener A, Günaydın GP, İçme F, Çelik GK, Kavaklı HŞ, Temrel TA. The accuracy of mainstream end-tidal carbon dioxide levels to predict the severity of chronic obstructive pulmonary disease exacerbations presented to the ED. Am J Emerg Med. 2014;32(5):408-411.
Cinar O, Acar YA, Arziman I, et al. Can mainstream end-tidal carbon dioxide measurement accurately predict the arterial carbon dioxide levels of patients with acute dyspnea in ED. Am J Emerg Med. 2012;30:358-361.
Nassar BS, Schmidt GA. Capnography during critical illness. Chest. 2016:149(2):576-585.
Caputo ND, Fraser RM, Paliga A et al. Nasal cannula end-tidal CO2 correlates with serum lactate levels and odds of operative intervention in penetrating trauma patients: a prospective cohort study. J Trauma Acute Care Surg. 2012;73:1202-1207.
Hunter CL, Silvestri S, Ralls G, Bright S, Papa L. The sixth vital sign: prehospital end-tidal carbon dioxide predicts in-hospital mortality and metabolic disturbances. Am J Emerg Med. 2014;32(2):160-165.
Hunter CL, Silvestri S, Dean M, Falk JL, Papa L. End-tidal carbon dioxide is associated with mortality and lactate in patients with suspected sepsis. Am J Emerg Med. 2013;31(1):64-71.
McGillicuddy DC, Tang A, Cataldo L, et al. Evaluation of end-tidal carbon dioxide role in predicting elevated SOFA and lactic acidosis. Intern Emerg Med. 2009;4:41-44.
Shapiro NI, Howell MD, Talmor D, Nathanson LA, Lisbon A, Wolfe RE, et al. Serum lactate as a predictor of mortality in emergency department patients with infection. Ann Emerg Med. 2005;45:524-528.
Levy, MM, Evans LE, Rhodes A. The surviving sepsis campaign bundle: 2018 update. Crit Care Med. 2018;46:997-1000.
Hunter CL, Silvestri S, Ralls G et al. A prehospital screening tool utilizing end-tidal carbon dioxide predicts sepsis and severe sepsis. Am J Emerg Med. 2016;34:813-819.
Guirgis FW, Williams DJ, Kalynych CJ, Hardy ME, Jones AE, Dodani S, Wears RL. End-tidal carbon dioxide as a goal of early sepsis therapy. Am J Emerg Med. 2014;32(11):1351-1356.
Kartal M, Eray O, Rinnert S, Gosku E, Bektas F, Eken C. ETCO2: a predictive tool for excluding metabolic disturbances in nonintubated patients. Am J Emerg Med. 2011;29: 65-69.
Solmeinpur H, Taghizadieh A, Niafar M, Rahmani F, Golzari SE, Esfanjani RM. Predictive value of capnography for diagnosis in patients with suspected diabetic ketoacidosis in the emergency department. West J Emerg Med. 2013;14:590-594.
Bou Chebl R, Madden B, Belsky J, Harmouche E, Yessayan L. Diagnostic value of end tidal capnography in patients with hyperglycemia in the emergency department. BMC Emerg Med. 2016;16:7.
Fearon DM, Steele DW. End-tidal carbon dioxide predicts the presence and severity of acidosis in children with diabetes. Acad Emerg Med. 2002;9:1373-1378.
Gilhotra Y, Porter P. Predicting diabetic ketoacidosis in children by measuring end-tidal CO2 via non-invasive nasal capnography. J Paediatr Child Health. 2007;43:677-680.
Dunham CM, Chirichella TJ, Gruber BS, et al. In emergently ventilated trauma patients, low end-tidal CO2 and low cardiac output are associated and correlate with hemodynamic instability, hemorrhage, abnormal pupils, and death. BMC Anesthesiol. 2013;13-20.
Deakin CD, Sado DM, Coats TJ, Davies G. Prehospital end-tidal carbon dioxide concentration and outcome in major trauma. J Trauma.2004;57:65-68.
Williams DJ, Guirgis FW, Morrissey TK, Wilkerson J, Wears RL, Kalynych C, Kerwin AJ, Godwin SA. End-tidal carbon dioxide and occult injury in trauma patients: ETCO2 does not rule out severe injury. Am J Emerg Med. 2016;34(11):2146-2149.
Manara A, D’hoore W, Thys F. Capnography as a diagnostic tool for pulmonary embolism: a meta-analysis. Ann Emerg Med. 2013;52:584-591.
Yoon YH, Lee SW, Jung DM et al. The additional use of end-tidal alveolar dead space fraction following D-dimer test to improve diagnostic accuracy for pulmonary embolism in the emergency department. Emerg Med J. 2010;27:663-667.
Hemnes AR, Newman AL, Rosenbaum B, et al. Bedside end-tidal CO2 tension as a screening tool to exclude pulmonary embolism. Eur Resp J. 2010;35:735-741.
Rias I Jacob B. Pulmonary embolism in Bradford, UK: role of end-tidal CO2 as a screening tool. Clin Med (Lond). 2014;14:128-133.
Yuksel M, Pekdemir M, Yilmaz S, et al. Diagnostic accuracy of noninvasive end-tidal carbon dioxide measurement in emergency department patients with suspected pulmonary embolism. Turk J Med Sci. 2016;46:84–90.
Williams D, Morrissey T, Caro D, Wears R, Kalynyc C. Side-stream qunatitative end-tidal carbon dioxide measurement as a triage tool in emergency medicine. Ann Emerg Med. 2011;58:S212-S213.

End Tidal Capnography in the Emergency Department

References

The Capnogram

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