Comparison of three different protocols for obtaining hemolysis.

Area of Science:

• Clinical Chemistry
• Laboratory Medicine
• Analytical Toxicology

Background:

• Hemolysis, the rupture of red blood cells, can significantly impact laboratory test results.
• Accurate clinical chemistry analysis requires understanding and mitigating pre-analytical variables like hemolysis.
• Different methods of inducing hemolysis may yield varying degrees of interference.

Purpose of the Study:

• To compare the interference of hemolysis on clinical chemistry analytes across three different automated analyzers.
• To evaluate four distinct methods for inducing in vitro hemolysis.
• To determine the most reliable method for assessing hemolysis interference in a laboratory setting.

Main Methods:

• Four methods were used to induce hemolysis: addition of pure hemoglobin, osmotic shock, aspiration through a blood collection needle, and freezing/thawing.
• Biochemistry parameters were measured on three analyzers: Architect c8000, Beckman Coulter AU680, and Cobas 6000 c501.
• Cut-off values were established based on the highest hemolysis index (H index) with bias within acceptance criteria.

Main Results:

• The freezing/thawing method did not yield usable results.
• Adding free hemoglobin showed the least interference across most analytes at H=0.5.
• Potassium and lactate dehydrogenase (LD) were significantly affected by hemolysis at H=0.5 on all platforms.
• The aspiration method was generally most sensitive to hemolysis interference, with several analytes affected at H=0.8.

Conclusions:

• Hemolysis interference is analyzer-dependent and method-specific.
• The aspiration method is generally more sensitive to hemolysis compared to other tested methods.
• Adding free hemoglobin is the most resistant method to hemolysis interference, making it a potentially more reliable standard for comparison.