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From the Research
Difference between Hemoglobin (Hb) on Arterial Blood Gas (ABG) and Hemoglobin (Hb) on Complete Blood Count (CBC)
- The difference between Hemoglobin (Hb) on Arterial Blood Gas (ABG) and Hemoglobin (Hb) on Complete Blood Count (CBC) has been studied in various research papers 1, 2, 3, 4, 5
- A study published in PloS one in 2015 found that there are no statistical differences and biases beyond USCLIA-determined limits between ABG- and laboratory-measured hemoglobin 1
- However, another study published in Anesthesia and analgesia in 2015 found that the median difference between the measured hemoglobin values was 0.4 g/dL, and the limits of agreement analysis demonstrated that the mean difference between measured hemoglobin values was 0.4 g/dL 2
- A study published in Anesthesia, essays and researches in 2022 found that Hb obtained by ABG analysis was significantly higher than lab value at all time points, with a mean difference of approximately 1 g/dL 3
- Another study published in Critical care in 2002 found a highly significant correlation between the coulter counter and blood gas analyzer methods of Hb measurement, with a mean difference of -4.3 g/l 4
- A study published in Diagnostics in 2022 found that reduced-volume blood gas analysis has acceptable accuracy and could replace complete blood count for the monitoring of Hb concentration in critically ill patients, with limits of agreement between ABG Hb and CBC Hb of −0.6 to 2.0 g/dL 5
Key Findings
- The studies suggest that there may be differences between Hemoglobin (Hb) on Arterial Blood Gas (ABG) and Hemoglobin (Hb) on Complete Blood Count (CBC), with some studies finding significant differences 2, 3 and others finding no significant differences 1
- The magnitude of the difference between the measured hemoglobin values varies between studies, with some finding a mean difference of 0.4 g/dL 2 and others finding a mean difference of approximately 1 g/dL 3
- The studies also suggest that reduced-volume blood gas analysis may be a viable alternative to complete blood count for monitoring Hb concentration in critically ill patients 5