Abstract
Capnometry is a measurement of end-tidal carbon dioxide (etCO2). EtCO2 represents a partial pressure or maximal concentration of CO2 at the end of exhalation. Capnography is a measurement and a graphic display of the characteristic waveform against time or volume, known as the capnogram. CO2 reflects cellular metabolism. There are four main stages of normal CO2 physiology: production, transport, buffering and elimination. The principal determinants of etCO2 are alveolar ventilation, pulmonary perfusion (cardiac output) and CO2 production. Capnography is most commonly used during endotracheal intubation to identify correct placement of an endotracheal tube. During acutely low cardiac output, as in cardiac arrest, decreased pulmonary blood flow becomes the primary determinant resulting in abrupt decrease of partial pressure of etCO2 (petCO2). If ventilation and chest compressions are constant — with the assumption that CO2 production is uniform — then the change in petCO2 reflects the changes in systemic and pulmonary blood flow. Ultimately, it can be used as a quantitative index of evaluating adequacy of ventilation and pulmonary flow during cardiopulmonary resuscitation (CPR) [1, 2
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Similar content being viewed by others
References
Anderson CT, Breen PH (2000) Carbon dioxide kinetics and capnography during critical care. Crit Care 4:207–215
Bijaoui E, Baconnier PF, Bates, JHT (2001) Mechanical output impedance of the lung determined from cardiogenic oscillations. J Appl Physiol 91:859–865
AARC Clinical Practice Guideline (2003) Capnography/capnometry during mechanical ventilation — 2003 revision and update. Respir Care 48:534–539
Gravenstein JS, Paulus DA (2004) Clinical perspectives. In: Gravenstein JS et al (eds) Capnography: clinical aspects. Cambridge University Press, Cambridge, UK pp 3–12
Casati A, Gullioli G, Passaretti R et al (2001) End tidal carbon dioxide monitoring in spontaneously breathing, nonintubated patients. Minerva Anesthesiol 67:161–164
Bhende, MS, LaCovey DC (2003) End-tidal carbon dioxide monitoring in the prehospital setting. Prehosp Emerg Care 5:208–213
Kline JA, Kubin AK, Patel MM et al (2000) Alveolar dead space as a predictor of severity of pulmonary embolism. Acad Emerg Med 7:611–617
Schmalisch G, Wauer RR, Foitzik B et al (2003) Influence of preterm onset of inspiration on tidal breathing parameters in infants with and without CLD. Respir Physiol Neurobiol 135:39–46
Grmec S (2002) Comparison of three different methods to confirm tracheal tube placement in emergency intubation. Intensive Care Med 28:701–704
Grmec S, Mally S (2004) Prehospital determination of tracheal tube placement in severe head injury. Emerg Med J 21:518–520
Grmec S (2005) Emergency endotracheal intubation: malposition and early detection. Internat J Intensive Care 12(2):81–86
Grmec S, Klemen P (2001) Does the end-tidal carbon dioxide (EtCO2) concentration have prognostic value during out-of-hospital cardiac arrest? Eur J Emerg Med 8:263–269
Grmec S, Kupnik D (2003) Does the Mainz Emergency Evaluation Scoring (MEES) in combination with capnometry (MEESc) help in the prognosis of outcome from cardiopulmonary resuscitation in a prehospital setting? Resuscitation 58:89–96
Grmec S, Lah K, Tušek-Bunc K (2003) Difference in end-tidal CO2 between asphyxia cardiac arrest and ventricular fibrillation/pulseless ventricular tachycardia cardiac arrest in the prehospital setting. Critical Care 7:R139–R144
Grmec S, Križmarić M, Mally S et al (2007) Utstein style analysis of out-of-hospital cardiac arrest-Bystander CPR and end expired carbon dioxide. Resuscitation 72:404–414
Kolar M, Križmarić M, Klemen P et al (2008) Partial pressure of end-tidal carbon dioxide successful predicts cardiopulmonary resuscitation in the field: a prospective observational study. Crit Care 12:R115
Križmarić M, Verlič M, Štiglic G et al (2009) Intelligent analysis in predicting outcome of out-of-hospital cardiac arrest. Comput Methods Programs Biomed 95(2 Suppl):S22–S32
Prosen G, Grmec Š, Kupnik D et al (2009) Focused echocardiography and capnography during resuscitation from pulseless electrical activity after out-of-hospital cardiac arrest. Crit Care 13(Suppl 1):S25–S26
Prosen G, Križmarić M, Završnik J et al (2010) Does echocardiographically confirmed pseudo-PEA in out of hospital cardiac arrest patients with constant values of petCO2 during compression pauses indicate modi_ ed treatment? J Int Med Res 38:1458–1467
Klemenc-Ketiš Z, Kersnik J, Grmec S (2010) The effect of carbon dioxide on near-death experiences in out-of-hospital cardiac arrest survivors: a prospective observational study. Crit Care 14:R56
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2011 Springer-Verlag Italia
About this paper
Cite this paper
Grmec, Š., Lah, K., Mally, Š. (2011). Capnometry/capnography in Prehospital Cardiopulmonary Resuscitation. In: Gullo, A. (eds) Anaesthesia, Pharmacology, Intensive Care and Emergency Medicine A.P.I.C.E.. Springer, Milano. https://doi.org/10.1007/978-88-470-2014-6_5
Download citation
DOI: https://doi.org/10.1007/978-88-470-2014-6_5
Publisher Name: Springer, Milano
Print ISBN: 978-88-470-2013-9
Online ISBN: 978-88-470-2014-6
eBook Packages: MedicineMedicine (R0)