• 1.

    American Society of Anesthesiologists Web site. Standards for basic anesthetic monitoring: 2003. Available at: www.asahq.org. Accessed Oct 27, 2008.

    • Search Google Scholar
    • Export Citation
  • 2.

    Hall LW, Clarke KW, Trim CM. Veterinary anaesthesia. 10th ed. St Louis: Elsevier Health Sciences, 2000.

  • 3.

    Beal MW, Hughes D. Vascular access: theory and techniques in the small animal emergency patient. Clin Tech Small Anim Pract 2000;15:101109.

  • 4.

    Hughes D, Beal MW. Emergency vascular access. Vet Clin North Am Small Anim Pract 2000;30:491507.

  • 5.

    Dunphy ED, Mann FA, Dodam JR. Comparison of unilateral versus bilateral nasal catheters for oxygen administration in dogs. J Vet Emerg Crit Care 2002;12:245251.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 6.

    Abramo TJ, Cowan MR, Scott SM, et al. Comparison of pediatric end-tidal CO2 measured with nasal/oral cannula circuit and capillary PCO2. Am J Emerg Med 1995;13:3033.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 7.

    Casati A, Gallioli G, Passaretta R, et al. End tidal carbon dioxide monitoring in spontaneously breathing, nonintubated patients. A clinical comparison between conventional sidestream and microstream capnometers. Minerva Anestesiol 2001;67:161164.

    • Search Google Scholar
    • Export Citation
  • 8.

    Fukuda K, Ichinohe T, Kaneko Y. Is measurement of end-tidal CO2 through a nasal cannula reliable? Anesth Prog 1997;44:2326.

  • 9.

    Goldman JM. A simple, easy, and inexpensive method for monitoring ETCO2 through nasal cannulae. Anesthesiology 1987;67:606.

  • 10.

    Tsui BC. A simple method with no additional cost for monitoring ETCO2 using a standard nasal cannulae. Can J Anaesth 1997;44:787788.

  • 11.

    Zimmerman D, Loken RG. Modified nasal cannula to monitor ETCO2. Can J Anaesth 1992;39:1119.

  • 12.

    Friesen RH, Alswang M. End-tidal PCO2 monitoring via nasal cannulae in pediatric patients: accuracy and sources of error. J Clin Monit 1996;12:155159.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 13.

    Hendricks JC, King LG. Practicality, usefulness, and limits of end-tidal carbon dioxide monitoring in critical small animal patients. J Vet Emerg Crit Care 1994;4:2939.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 14.

    Pang D, Hethey J, Caulkett NA, et al. Partial pressure of endtidal CO2 sampled via an intranasal catheter as a substitute for partial pressure of arterial CO2 in dogs. J Vet Emerg Crit Care 2007;17:143148.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 15.

    Bland JM, Altman DG. Statistical methods for assessing agreement between two methods of clinical measurement. Lancet 1986;1:307310.

  • 16.

    Teixeira Neto FJ, Carregaro AB, Mannarino R, et al. Comparison of a sidestream capnograph and a mainstream capnograph in mechanically ventilated dogs. J Am Vet Med Assoc 2002;221:15821585.

    • Crossref
    • Search Google Scholar
    • Export Citation

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Agreement between values for arterial and end-tidal partial pressures of carbon dioxide in spontaneously breathing, critically ill dogs

Efrat Kelmer DVM, MS, DACVECC1, Lindsey C. Scanson2, Ann Reed MS3, and Lydia C. Love DVM4
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  • 1 Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, TN 37996.
  • | 2 Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, TN 37996.
  • | 3 Office of Information Technology, University of Tennessee, Knoxville, TN 37996.
  • | 4 Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, TN 37996.

Abstract

Objective—To determine agreement between arterial partial pressures of carbon dioxide (PaCO2) and end-tidal partial pressures of carbon dioxide (PETCO2) measured with a nasal catheter in spontaneously breathing, critically ill dogs.

Design—Validation study.

Animals—26 client-owned dogs admitted to an intensive care unit for various conditions.

Procedures—PaCO2 was measured with a commercial blood gas analyzer, and PETCO2 was measured with a sidestream capnograph attached to a nasal catheter. Measurements were obtained twice (ie, with and without supplemental oxygen). Paired values were compared by means of the Pearson correlation method. Level of agreement was assessed by means of the Bland-Altman method.

Results—Mean difference between PaCO2 and PETCO2 when dogs did not receive supplemental oxygen (mean ± SD, 3.95 ± 4.92 mm Hg) was significantly lower than mean difference when dogs did receive supplemental oxygen (6.87 ± 6.42 mm Hg). Mean difference in dogs with a condition affecting the respiratory system (8.55 ± 5.43 mm Hg) was significantly higher than mean difference in dogs without respiratory tract disease (3.28 ± 3.23 mm Hg). There was a significant linear correlation and good agreement between measured values of PaCO2 and PETCO2. Catheter size, ventilatory status, and outcome were not significantly associated with mean difference between PaCO2 and PETCO2.

Conclusions and Clinical Relevance—Results suggested that nasal capnography is a clinically relevant method of estimating PaCO2 in spontaneously breathing, critically ill dogs, but that values should be interpreted with caution in dogs receiving supplemental oxygen and in dogs with conditions affecting the respiratory system.

Abstract

Objective—To determine agreement between arterial partial pressures of carbon dioxide (PaCO2) and end-tidal partial pressures of carbon dioxide (PETCO2) measured with a nasal catheter in spontaneously breathing, critically ill dogs.

Design—Validation study.

Animals—26 client-owned dogs admitted to an intensive care unit for various conditions.

Procedures—PaCO2 was measured with a commercial blood gas analyzer, and PETCO2 was measured with a sidestream capnograph attached to a nasal catheter. Measurements were obtained twice (ie, with and without supplemental oxygen). Paired values were compared by means of the Pearson correlation method. Level of agreement was assessed by means of the Bland-Altman method.

Results—Mean difference between PaCO2 and PETCO2 when dogs did not receive supplemental oxygen (mean ± SD, 3.95 ± 4.92 mm Hg) was significantly lower than mean difference when dogs did receive supplemental oxygen (6.87 ± 6.42 mm Hg). Mean difference in dogs with a condition affecting the respiratory system (8.55 ± 5.43 mm Hg) was significantly higher than mean difference in dogs without respiratory tract disease (3.28 ± 3.23 mm Hg). There was a significant linear correlation and good agreement between measured values of PaCO2 and PETCO2. Catheter size, ventilatory status, and outcome were not significantly associated with mean difference between PaCO2 and PETCO2.

Conclusions and Clinical Relevance—Results suggested that nasal capnography is a clinically relevant method of estimating PaCO2 in spontaneously breathing, critically ill dogs, but that values should be interpreted with caution in dogs receiving supplemental oxygen and in dogs with conditions affecting the respiratory system.

Contributor Notes

Dr. Kelmer's present address is Koret School of Veterinary Medicine, The Hebrew University of Jerusalem, PO Box 12, Rehovot, Israel, 76100.

Supported by an internal grant from the College of Veterinary Medicine, University of Tennessee.

Presented in abstract form at the 14th International Veterinary Emergency and Critical Care Symposium, Phoenix, September 2008.

Address correspondence to Dr. Kelmer (kelmere1@gmail.com).