Abstract: Chapter 30 Capnography Linda S. Barter, Linda S. BarterSearch for more papers by this authorAlessia Cenani, Alessia CenaniSearch for more papers by this author Linda S. Barter, Linda S. BarterSearch for more papers by this authorAlessia Cenani, Alessia CenaniSearch for more papers by this author Book Editor(s):Jamie M. Burkitt Creedon, Jamie M. Burkitt Creedon School of Veterinary Medicine, University of California, Davis, California, USASearch for more papers by this authorHarold Davis, Harold Davis Retired, University of California, Clinical Educational Veterinary Consultant, California, USASearch for more papers by this author First published: 17 February 2023 https://doi.org/10.1002/9781119581154.ch30 AboutPDFPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShareShare a linkShare onEmailFacebookTwitterLinkedInRedditWechat Summary A capnometer detects the highest and lowest values for carbon dioxide (CO 2 ) in the respired gas and reports them as inspired and end-expired partial pressures or concentrations. There are two types of CO 2 analyzers: mainstream and sidestream. In smaller patients, mainstream CO 2 analyzers are technically superior to sidestream analyzers. Several techniques are available for measuring CO 2 including infrared absorption, Raman scattering, and mass spectrometry. This chapter presents indications for performing capnography or capnometry. Capnography or capnometry may be useful into situations in which it is challenging to determine visually the correct endotracheal tube placement. Capnography is most accurate in intubated patients but can also be used in awake, non-intubated patients for continuous noninvasive PCO 2 monitoring. Evaluation of capnographic waveforms can aid in the detection of patient or equipment abnormalities. References Middleton , D.J. , Ilkiw , J.E. , and Watson , A.D. ( 1981 ). Arterial and venous blood gas tensions in clinically healthy cats . Am. J. Vet. Res. 42 : 1609 – 1611 . Ilkiw , J.E. , Rose , R.J. , and Martin , I.C.A. ( 1991 ). A comparison of simultaneously collected arterial, mixed venous, jugular venous and cephalic venous blood samples in the assessment of blood-gas and acid–base status in the dog . J. Vet. Intern. Med. 5 : 294 – 298 . Badgwell , J.M. and Heavner , J.E. ( 1991 ). End-tidal carbon dioxide pressure in neonates and infants measured by aspiration and flow-through capnography . J. Clin. Monit. 7 : 285 – 288 . Pascucci , R.C. , Schena , J.A. , and Thompson , J.E. ( 1989 ). Comparison of a sidestream and mainstream capnometer in infants . Crit. Care Med. 17 : 560 – 562 . Schmalisch , G. , Foitzik , B. , Wauer , R.R. et al. ( 2001 ). Effect of apparatus dead space on breathing parameters in newborns: "flow-through" versus conventional techniques . Eur. Respir. J. 17 : 108 – 114 . Pearsall , M.F. and Feldman , J.M. ( 2014 ). When does apparatus dead space matter for the pediatric patient? Anesth. Analg. 118 ( 4 ): 776 – 780 . Kugelman , A. , Zeiger-Aginsky , D. , Bader , D. et al. ( 2008 ). A novel method of distal end-tidal CO 2 capnography in intubated infants: comparison with arterial CO 2 and with proximal mainstream end-tidal CO 2 . Pediatrics 122 : e1219 – e1224 . Hagerty , J.J. , Kleinman , M.E. , Zurakowski , D. et al. ( 2002 ). Accuracy of a new low-flow sidestream capnography technology in newborns: a pilot study . J. Perinatol. 22 : 219 – 225 . Pokorná , M. , Nečas , E. , Kratochvíl , J. et al. ( 2010 ). A sudden increase in partial pressure end-tidal carbon dioxide (PETCO 2 ) at the moment of return of spontaneous circulation . J. Emerg. Med. 38 ( 5 ): 614 – 621 . Brainard , B.M. , Boller , M. , Fletcher , D.J. et al. ( 2012 ). RECOVER evidence and knowledge gap analysis on veterinary CPR. Part 5: Monitoring . J. Vet. Emerg. Crit. Care 22 ( Suppl 1 ): S65 – S84 . Advanced Monitoring and Procedures for Small Animal Emergency and Critical Care, Second Edition ReferencesRelatedInformation