Effects of different centrifugation conditions on clinical chemistry and Immunology test results

Abstract

BackgroundThe effect of centrifugation time of heparinized blood samples on clinical chemistry and immunology results has rarely been studied. WHO guideline proposed a 15 min centrifugation time without citing any scientific publications. The centrifugation time has a considerable impact on the turn-around-time.MethodsWe investigated 74 parameters in samples from 44 patients on a Roche Cobas 6000 system, to see whether there was a statistical significant difference in the test results among specimens centrifuged at 2180 g for 15 min, at 2180 g for 10 min or at 1870 g for 7 min, respectively. Two tubes with different plasma separators (both Greiner Bio-One) were used for each centrifugation condition. Statistical comparisons were made by Deming fit.ResultsTubes with different separators showed identical results in all parameters. Likewise, excellent correlations were found among tubes to which different centrifugation conditions were applied. Fifty percent of the slopes lay between 0.99 and 1.01. Only 3.6 percent of the statistical tests results fell outside the significance level of p < 0.05, which was less than the expected 5%. This suggests that the outliers are the result of random variation and the large number of statistical tests performed. Further, we found that our data are sufficient not to miss a biased test (beta error) with a probability of 0.10 to 0.05 in most parameters.ConclusionA centrifugation time of either 7 or 10 min provided identical test results compared to the time of 15 min as proposed by WHO under the conditions used in our study.

The analytic impact of a reduced centrifugation step on chemistry and immunochemistry assays: an evaluation of the Modular Pre-Analytics

“…Despite this, the influence of a shorter centrifugation time has been scantly investigated. 7 -10 Recently, Minder et al 11 reported on the effect of different centrifugation conditions on a broad range of chemistry and immunochemistry assays in human plasma. No significant difference was observed in the analytical outcome after whole blood was centrifuged according to the WHO guidelines (15 min at 2180 Â g 3 ) or for 10 min at 2180 Â g or 7 min at 1870 Â g. The data by Minder et al suggest that centrifugation time can be reduced from 15 to 7 min, a 47% decrease that, according to the authors, leads to a significantly faster intralaboratory TAT.…”

Hematological and clinical chemistry changes induced by acute stress during handling and capture of catfish (Ictalurus punctatus)

“…La sangre de cada muestra fue dividida en dos partes, una de ellas se utilizó para realizar el hemograma, y el resto se centrifugó a 3000 rpm por 15 min a temperatura ambiente para la extracción del plasma. El producto fue almacenado en refrigeración (4°C) para definir su bioquímica sanguínea posteriormente (18).…”

“…Each sample was divided into two parts; one of which was used for hematology, and the rest was centrifuged at 3000 rpm for 15 min at room temperature to extract plasma. The product was refrigerated (4°C) to later define blood chemistry (18).…”

A ‘smart’ tube holder enables real-time sample monitoring in a standard lab centrifuge

“…Unoptimized centrifugation can result in unnecessary over centrifuging (by virtue of waiting longer than needed) or material waste (by virtue of not recovering all of the material). This is well illustrated by several publications that show how well accepted clinical centrifugation protocols are sometimes longer than needed [ 7 – 9 ], lengthening diagnostic procedures and potentially adding to health care costs.…”