Venous Samples Are a Less-Painful Starting Point for the Evaluation of Patients with Acute Exacerbation of COPD


Am Fam Physician. 2016 Nov 1;94(9):757.

Clinical Question

In patients with an acute exacerbation of chronic obstructive pulmonary disease (COPD), is a venous blood sample as useful as an arterial sample?

Bottom Line

There is very good agreement between arterial and venous measurements of pH and bicarbonate, and fairly good agreement at higher levels between arterial and peripheral measures of oxygen saturation. These authors suggest an algorithm for patients with acute exacerbation of COPD that includes an arterial blood gas analysis only if the patient's initial pulse oximetry is less than 80% or if the venous pH is less than 7.35, which would obviate the need for two-thirds of arterial blood gasses. A more conservative approach would also include an arterial blood gas analysis for patients with oxygen saturation between 80% and 84%, where

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This series is coordinated by Sumi Sexton, MD, Associate Deputy Editor.

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Mar 15, 2017

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