Hemolysis detection for ethanol measurement in whole blood samples before centrifugation: HemCheck device evaluation

Abstract

Background: As previously reported, the measurement of ethanol can also be affected by interference from hemolysis. This is a matter of concern since ethanol is widely regarded as the most commonly abused substance globally. When sample re-collection is ordered to eliminate hemolysis effects for ethanol testing, this can have unfavourable consequences for these patients. Rapid detection of hemolysed specimens would alleviate some issues associated with forensic samples. This study aimed to assess the qualitative analytical performance of a novel point-of-care testing device per the guidelines specified in CLSI-EP-12A document. HemCheck™ is a novel POCT device that qualitatively detects free-hemoglobin levels on the specimen shortly after drawing the sample. Methods: The system consists of two components. One is a cartridge with a needle that is used to transfer a small volume of whole blood from a vacuum tube to vertical and lateral flow filtration. The second component is the reader. The consumable cartridges are designed to be inserted into the reader without requiring the syringe or blood collection tube removal. A red indicator led illuminates, indicating that the sample has been hemolysed. To assess the imprecision of the method, we determined the C5-C95 interval and C50, using the Roche Cobas clinical chemistry analyser as the comparator. For this study, we utilised residual samples. Results: Our C50 concentrations were 45 mg/dL, the C5-C95 30 mg/dL and 60 mg/dL, respectively. Two methods reveal an overall agreement of 89.2%. The diagnostic sensitivity and specificity of the study showed a positive agreement of 95.7% and a negative agreement of 80.0%. The calculated Cohen's Kappa value was 77.3%. Conclusion: According to current literature, a bias in ethanol levels can be noticed even with small free hemoglobin concentrations. When it came to forensic samples, this bias was crucial. Our study confirmed that the HemCheck device has acceptable analytical performance, as outlined in the CLSI-EP-12A document. Although the possible beneficial impacts of the innovative POCT hemolysis detection device on the preanalytical phase are proposed, we have not studied them in this study.

Keywords

• hemolysis
• pre-analytical phase
• ethanol
• point-of-care testing
• quality improvement