Effects of Hyperventilation on Venous-Arterial Bicarbonate Concentration Difference: A Possible Pitfall in Venous Blood Gas Analysis


Objectives: Recent reports on venous blood gas analysis have shown that venous bicarbonate concentration is useful in the evaluation of the body acid-base status. Most of these reports have been based on the Bland-Altman analysis comparing arterial and venous blood gas values. We intended to elucidate any factors that decrease the agreement between venous and arterial bicarbonate concentrations, which might impair the usefulness of venous blood gas analysis. Methods: Healthy volunteers and patients with various diseases (n = 141) were evaluated by simultaneous arterial and venous blood sampling and Bland-Altman analysis. The venous-arterial bicarbonate concentration difference was compared between healthy volunteers and untreated respiratory alkalosis patients. Intentional hyperventilation (30 or 60 breaths/min, for 3 min) was also performed on 6 healthy volunteers and the venous-arterial bicarbonate concentration difference was evaluated. Results: The relative average bias in bicarbonate concentration was 2.00 mEq/l with venous bicarbonate higher than arterial bicarbonate with 95% limits of agreement of ±4.15 mEq/l. Hyperventilation challenges increased the venous-arterial bicarbonate concentration difference in an intensity-dependent manner. The venous-arterial bicarbonate concentration difference was higher in untreated respiratory alkalosis patients than in healthy volunteers (P < 0.01). Conclusion: Although venous bicarbonate may be useful to evaluate the body acid-base status, hyperventilation increases the venous-arterial bicarbonate concentration difference. Physicians should keep this phenomenon in mind.

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A. Umeda, K. Kawasaki, T. Abe, T. Yamane and Y. Okada, "Effects of Hyperventilation on Venous-Arterial Bicarbonate Concentration Difference: A Possible Pitfall in Venous Blood Gas Analysis," International Journal of Clinical Medicine, Vol. 5 No. 2, 2014, pp. 76-80. doi: 10.4236/ijcm.2014.52014.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] A. M. Kelly, “Review Article: Can Venous Blood Gas Analysis Replace Arterial in Emergency Medical Care,” Emergency Medicine Australasia, Vol. 22, No. 6, 2010, pp. 493-498.
[2] A. Umeda, K. Kawasaki, T. Abe, et al., “Hyperventilation and Finger Exercise Increase Venous Arterial PCO2 and pH Differences,” American Journal of Emergency Medicine, Vol. 26, No. 9, 2008, pp. 975-980.
[3] B. L. Lim and A. M. Kelly, “A Meta-Analysis on the Utility of Peripheral Venous Blood Gas Analyses in Exacerbations of Chronic Obstructive Pulmonary Disease in the Emergency Department,” European Journal of Emergency Medicine, Vol. 17, No. 5, 2010, pp. 246-248.
[4] J. M. Bland and D. G. Altman, “Statistical Methods for Assessing Agreement between Two Methods of Clinical Measurement,” Lancet, Vol. 1, No. 8476, 1986, pp. 307-310. http://dx.doi.org/10.1016/S0140-6736(86)90837-8
[5] Y. Okada, T. Satoh, S. Kuwana, et al., “Electrical Stimulation of the Rabbit Pulmonary Artery Increases Respiratory Output,” Respiratory Physiology & Neurobiology, Vol. 140, No. 3, 2004, pp. 209-217.
[6] F. Shirani, R. Salehi, A. E. Naini, et al., “The Effects of Hypotension on Differences between the Results of Simultaneous Venous and Arterial Blood Gas Analysis,” Journal of Research in Medical Sciences, Vol. 16, No. 2, 2011, pp. 188-194.
[7] A. M. Kelly, R. McAlpine and E. Kyle, “Agreement between Bicarbonate Measured on Arterial and Venous Blood Gases,” Emergency Medicine Australasia, Vol. 16, No. 5-6, 2004, pp. 407-409.
[8] W. G. Herrington, H. J. Nye, M. S. Hammersley, et al., “Are Arterial and Venous Samples Clinically Equivalent for the Estimation of pH, Serum Bicarbonate and Potassium Concentration in Critically Ill Patients?” Diabetic Medicine, Vol. 29, No. 1, 2012, pp. 32-35.
[9] G. Malatesha, N. K. Singh, A. Bharijia, et al., “Comparison of Arterial and Venous pH, Bicarbonate, PCO2 and PO2 in Initial Emergency Department Assessment,” Emergency Medicine Journal, Vol. 24, No. 8, 2007, pp. 569-571. http://dx.doi.org/10.1136/emj.2007.046979
[10] P. Middleton, A. M. Kelly, J. Brown, et al., “Agreement between Arterial and Central Venous Values for pH, Bicarbonate, Base Excess, and Lactate,” Emergency Medicine Journal, Vol. 23, No. 8, 2006, pp. 622-624.

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