Objective: to verify the functioning and analytical quality of the Landwind LW D3600 hematology analyzer during clinical practice through sigma metrics and power charts, highlighting the importance of daily preventive maintenance.
Methods: This prospective cross-sectional study was developed at the University Clinic in Lima, Peru during 2016. Twelve haematological parameters were evaluated - (×10³/μL), RBC (×10⁶/μL), HB (ɡ/dL), PLT (×10³/μL), HCT (%), and MCV (fL), among others- in two phases: 1) evaluation and estimation of the sigma metric, and 2) 14-day evaluation of the performance of the parameters hematological. In addition, three daily cleaning maintenance systems (electrical, washing, and complete) were compared. Myth-3D control reagents MYTHIC18 of 3 control levels and a single batch were used.
Results: In both phases WBC and PLT had a great sigma performance (≥7), and the erythroid parameters (RBC, HB, HCT, and MCV) presented low performance (≤4), where only MCV and RBC (each with Pfr ≤0.6) could be kept under quality with the use of the multi-rule 13s/22s/R4s/41s with 4 levels of control. The system of preventative maintenance of complete cleaning improved the quality of analysis showing low imprecision results (p=0.005).
Conclusion: the daily evaluation under the sigma metric allowed verifying the quality of the demonstrating a heterogeneous performance and illustrating a process of analytical evaluation in the hematological laboratory.
Keywords: verification, hematology analyzer, quality control, complete blood count, maintenance, six sigma.