Abgs Vs Vbgs. As shown in table 1 vbgs had low sensitivity and or specificity for detecting most blood gas abnormalities. A 2014 british systematic review pooling data from 100 studies showed that ph agrees reasonably at all values best agreement at normal values the vbg ph is 0 03 units less than the abg ph but abnormal co2 and lactate levels didn t really agree between abgs and vbgs.
Published normal venous only one complete set of normal vbgs found and arterial values were used to determine normal vs abnormal results for ph co 2 and hco3. In conclusion the vbg is a useful less painful and more easily gathered test than abg to asses for acidosis and hypercarbia. Venous blood gases vbg are widely used in the emergency setting in preference to arterial blood gases abg as a result of research published since 2001 the weight of data suggests that venous ph has sufficient agreement with arterial ph for it to be an acceptable alternative in clinical practice for most patients.
This improved accuracy substantially compared to assuming that abg values are roughly equal to vbg values.
Many studies have tried to determine the mean difference md between abgs and vbgs. Abgs are drawn for a variety of reasons. When that happens prompt and quick assessment is done before treatment is even started. Venous blood gases vbg s blood sample taken from either peripheral or central veins can serve as an alternative to an abg when evaluating patients with metabolic and respiratory disturbances.
