The comparison between centrifuged hematocrit and automated method for hematocrit determination

Abstract

Hematocrit (Hct) measurement is a commonly used method for assessing preoperative anemia and guiding blood transfusion decisions. This measurement is primarily performed using standard laboratory instruments. In routine practice, however, centrifugation methods are also used because they are convenient and provide rapid results. Objective: To compare the red blood cell concentration relative to total blood volume (Hematocrit) obtained using a centrifugation method with that obtained using an automated laboratory analyzer. Methods: This was a comparative cross-sectional study with prospective data collection conducted in adult patients aged 18 years and older who underwent surgery at Maharaj Nakhon Ratchasima Hospital. A total of 268 patients were enrolled. Blood samples from each patient were analyzed to determine red blood cell concentration relative to total blood volume using both a centrifugation method and an automated analyzer at the central laboratory. The results from the two methods were compared and statistically analyzed. Results: Hematocrit obtained from the two methods differed; however, the values demonstrated a strong positive linear correlation. The Pearson correlation coefficient was 0.96. The hematocrit measured by the centrifuge had a mean of 34.8 ± 7%, and the hematocrit obtained from the automated analyzer had a mean of 33.1 ± 7%. The mean difference between the two measurement methods was 1.67%. Data with an acceptable level of discrepancy (error less than 4%) accounted for 95.15% of all measurements. Conclusion: Hematocrit obtained from the two measurement methods demonstrated similar trends, with values derived from the centrifugation method tending to be higher than those obtained from the automated analyzer. The observed discrepancy was within an acceptable range.