COMPARISON OF AUTOMATED COMPLETE BLOOD COUNT PARAMETERS AND HEMOLYSIS OCCURRENCE FROM VACUUM AND NON-VACUUM K2EDTA TUBES

Background: The preanalytical factors, including tube type and storage duration, may influence CBC results and hemolysis. Nowadays, blood collection using K₂EDTA, both vacuum and non-vacuum tubes, is widely utilized in clinical laboratories for complete blood count (CBC) analysis. However, the impact of vacuum-induced negative pressure and the anticoagulant-to-blood ratio in under-filled tubes on sample integrity remains a concern. Objective: This study aimed to compare the performance of K₂EDTA vacuum and non-vacuum blood collection tubes, including under-filled non-vacuum tubes, in automated CBC parameters and to assess hemolysis occurrence at different time points. Methods: Blood samples from 30 healthy subjects were collected into three different K₂EDTA blood collection tubes: vacuum, non-vacuum, and non-vacuum tubes with under-filled volumes. CBC parameters, including RBC, Hb, Hct, MCV, MCH, MCHC, RDW, WBC, PLT, and MPV, were analyzed at 0 hours, 3 hours, and 24 hours post-collection. Hemolysis was assessed via spectrophotometry at 540 nm. Results: No statistically significant differences were observed in CBC parameters among the three groups at 0 hours. However, significant differences occurred at 3 hours post-collection, including WBC and PLT in vacuum tubes, MCV in non-vacuum tubes, RDW in under-filled tubes, and MPV in all tube types. At 24 hours, all tube types showed significant changes in MCV, MCHC, RDW, and MPV, while RBC showed only changes in vacuum tubes. The highest hemolysis levels occurred in vacuum tubes at 0 hours, whereas under-filled tubes exhibited increased hemolysis at 3 and 24 hours. Conclusion: The results indicated that all three tube types are suitable for hematological analysis if processed within 3 hours. However, the risk of hemolysis in vacuum tubes should be carefully considered, particularly in individuals with suspected hemolysis.