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Background: Several methods exist to reduce the number of arterial blood gases (ABGs). One method, Roche v-TAC, has been evaluated in different patient groups. This paper aggregates data from these studies, in different patient categories using common analysis criteria., Research Design and Methods: We included studies evaluating v-TAC based on paired arterial and peripheral venous blood samples. Bland-Altman analysis compared measured and calculated arterial values of pH, PCO 2 , and PO 2 . Subgroup analyses were performed for normal, chronic hypercapnia and chronic base excess, acute hyper- and hypocapnia, and acute and chronic base deficits., Results: 811 samples from 12 studies were included. Bias and limits of agreement for measured and calculated values: pH 0.001 (-0.029 to 0.031), PCO 2 -0.08 (-0.65 to 0.49) kPa, and PO 2 0.04 (-1.71 to 1.78) kPa, with similar values for all sub-group analyses., Conclusion: These data suggest that v-TAC analysis may have a role in replacing ABGs, avoiding arterial puncture. Substantial data exist in patients with chronic hypercapnia and chronic base excess, acute hyper- and hypocapnia, and in patients with relatively normal acid-base status, with similar bias and precision across groups and across study data. Limited data exist for patients with acute and chronic base deficits.

Arterial blood gas (ABG) analysis is an essential tool in the clinical assessment of acutely ill patients. Venous to arterial conversion (v-TAC), a mathematical method, has been developed recently to convert peripheral venous blood gas (VBG) values to arterialized VBG (aVBG) values. The aim of this study was to test the validity of aVBG compared to ABG in an emergency department (ED) setting. Twenty ED patients were included in this study. ABG and three aVBG samples were collected from each patient. The aVBG samples were processed in three different ways to investigate appropriate sample handling. All VBG samples were arterialized using the v-TAC method. ABG and aVBG samples were compared using Lin's concordance correlation coefficient (CCC), Bland-Altman plots and misclassification analysis. Clinical acceptable threshold of aVBG value deviance from ABG values were ± 0.05 pH units, ± 0.88 kPa pCO 2 and ± 0.88 kPa pO 2 . CCC revealed an agreement in pH and pCO 2 parameters for both aVBG in comparison to ABG. In all aVBG samples, an overestimation of pO 2 compared to ABG was observed. Bland-Altman plot revealed clinically acceptable mean difference and limits-of-agreement intervals between ABG and aVBG pH and pCO 2 , but not between ABG and aVBG pO 2 . Arterialization of VBG using v-TAC is a valid method for measuring pH and pCO 2 , but not for pO 2 . Larger clinical studies are required to evaluate the applicability of v-TAC in different patient subpopulations.