Application of the delta check-first dilution principle to reduce turnaround time for blood magnesium level testing

Abstract

Background: Magnesium levels testing in the laboratory with an automatic machine, such as Roche cobas c503 analyzer MG gen 2 has a measuring range is 0.243-4.86 mg/dL. Values that exceed measuring range of the automated machine must re-analyze by diluting the specimen before analysis resulting in prolonging the turnaround time. Very high magnesium level may affect severe symptoms of preeclampsia patients and mortality. Therefore, we are interested in reducing the turnaround time for blood magnesium levels testing by applying the principle of delta check and laboratory information system (LIS), which is called "delta check-first dilution (DCFD)"

Objective: To examine the application of the delta check-first dilution principle to reduce the turnaround time for serum magnesium testing.

Material and Methods: Setting up the LIS system to check against the latest results within the past 3 days. If a patient has prior a magnesium test and the magnesium level exceeds the measuring range, the LIS will activate the auto-dilute sample from the first-time test and compare the turnaround time.

Result: Using the DCFD principle, the median turnaround time was reduced from 76 min to 63 min, which was statistically significant. (p=0.004) This measure improves the reporting of magnesium results higher than the measuring range. The expected turnaround time increased from 62.0 percent to 86.5 percent.

Conclusion: Using the delta check-first dilution principle, the LIS was set to dilute the analyte sample from the first test. It can help reduce the turnaround time for results and increase the ability to report results within the specified period.