BACKGROUND: A portable glucometer is commonly used to immediately check the blood glucose level. In the anesthetic field, some blood gas analyzers can also give a rapid indication of the blood sugar level but the accuracy is unknown. Therefore, this study assessed the accuracy of the blood glucose values measured by either a blood gas analyzer or portable glucometer.

METHODS: Venous blood from diabetic patients was used to measure the glucose level with either a blood gas analyzer or a portable glucometer. The difference and 5% deviation from reference values was analyzed. These values were also assessed using a Bland-Altman plot and clinical significance was examined using a Clarke error grid.

RESULTS: The differences from the reference values were smaller using the blood gas analyzer (1.3 ± 7.8 mg/dl) than using the portable glucometer (-5.1 ± 16.7 mg/dl)(P < 0.01). 73.4% of the values measured by the blood gas analyzer and 40.0% of those measured by the portable glucometer were within 5% of the reference value. The 95% limits of agreement in the difference ranged from -14.3 to 16.9 in the blood gas analyzer and -38.5 to 28.2 in the portable glucometer. Error grid analysis showed that 100% of the values measured by the blood gas analyzer were located in zone A. When locating the values measured using the portable glucometer, 95.6% were located in zone A, and the remaining 4.4% are located in zone B.

CONCLUSIONS: The blood gas analyzer measures the blood glucose more accurately than the portable glucometer. However, the blood glucose values measured by the portable glucometer are clinically acceptable.