[Determination of hemoglobin concentration using the hemoglobin azide method in traumatic emergencies]

The present study examined the clinical practicability of a new hemoglobin measurement device based on a modified azide-methemoglobin reaction (HiN3 method) in trauma patients. The accuracy of the HiN3 method was compared to the internationally well accepted hemiglobincyanide method (HiCN method) in arterial, capillary, and venous blood samples.

1. Comparison of the methods. In 62 trauma patients, hemoglobin measurements using the HiN3 method were compared to results obtained by the HiCN method. Blood samples were taken simultaneously from the same patient to evaluate each measurement procedure in arterial (group 1), capillary (group 2), and venous blood samples (group 3). 2. Accuracy. To evaluate the accuracy of both methods we compared two venous blood samples taken simultaneously from the same patient. 3. Reproducibility. For measurement of the reproducibility of the HiN3 method, the first two results of each three-time-measurement were compared. Statistical analysis of the results was performed using regression analysis.

1. Comparison of the methods. Comparing the results of hemoglobin measurements resulting from the HiN3 and HiCN methods, a strong correlation was found in arterial (Fig. 2), capillary (Fig. 3), and venous blood (Fig. 4). 2. Accuracy. The HiN3 method had an accuracy of +/- 1.47% and the HiCN method +/- 2.55%. 3. The reproducibility of the HiN3 method was +/- 1.25% (Fig. 5); however, one pair of samples did show a significantly different initial value (Hb 8.4 g/dl in I, but 10.4 g/dl in I and III).

From our examinations in trauma patients, we can recommend this easy to handle device, particularly for acute diagnostic purposes in emergency patients and for trend evaluations both in the hospital and in the prehospital period for rapid and precise hemoglobin determinations.