Sysmex XN-L blood analyzer maintenance and troubleshooting

In terms of precision, the repeatability CV of WBC in whole blood mode is not greater than 3.0%, RBC is not greater than 1.5%, HGB is not greater than 1.5%, HCT is not greater than 1.5%, and PLT is not greater than 4.0%. In pre dilution mode, the corresponding CV will be relaxed, such as WBC not exceeding 5.0%, RBC not exceeding 4.5%, and PLT not exceeding 12.0%. In terms of carrying pollution, WBC, RBC, HGB, HCT, PLT usually require no more than 1.0%, and white blood cell classification items generally do not exceed 2.0% or specific absolute values. The stability of the sample after collection is affected by temperature. WBC, RBC, and HGB can remain stable for about 72 hours at 18 to 26 ℃, HCT for about 8 hours, and PLT for about 48 hours; Under the conditions of 2 to 8 ℃, some parameters have different stabilization times. Before testing, it is necessary to restore room temperature and mix thoroughly.

In terms of software data storage capacity, it can store approximately 100000 samples, 10000 patient information, 200 wards, 200 doctor names, 2000 analysis registration records, 20 calibration logs for each analyzer, 99 QC files for each analyzer, 300 image points per file, 5000 reagent replacement logs, and 5000 maintenance logs. Quality control supports L-J control chart, approximately 300 points x 96 files, and X-barM control chart, 300 points x 3 files.

Reagents, consumables, and calibration systems

The XN-L series uses a designated reagent system. CELLPACK DCL is a diluent and sheath containing sodium chloride, Tris buffer EDTA-2K， Store at a temperature of 2 to 35 ℃ for 60 days after opening the bottle. CELLPACK DST is a concentrated reagent that needs to be connected to the designated reagent preparation device of Sysmex, stored at 15 to 30 ℃, and opened for 60 days. SULFULYSER is used for hemoglobin measurement, containing sodium dodecyl sulfate, stored at 1 to 30 ℃, and opened for 60 days. Lysercell WDF is used for hemolysis and leukocyte treatment, 90 days after opening the bottle. Fluorocell WDF is a fluorescent dye containing polyacetylene pigment, methanol, and ethylene glycol. It should be stored in the dark at 2 to 35 ℃ and opened for 90 days. CELLCLEAN AUTO is a strong alkaline cleaning solution containing sodium hypochlorite, used for pipeline cleaning and stored at 1 to 30 ℃.

Both the quality control material XN-L CHECK and the calibration material XN CAL need to be refrigerated at 2 to 8 ℃ in the dark. Use within 15 days after opening XN-L CHECK and within 4 hours after opening XN CAL. The calibration items cover WBC, RBC, HGB, HCT, and PLT. The quality control barcode usually uses CODE128, which is a fixed string of "QC -" followed by an 8-digit batch number and a 1-digit checksum. If barcode reading fails, the system may automatically assign a sample number starting with ERR; QC samples, background checks, precision checks, and calibration samples also have specific prefixes. Daily use should avoid using expired reagents, repeatedly connecting opened bottles of reagents, and using non specified sample tubes or sampling adapters. A specialized adapter is required for the 15 mm sample tube. The metal parts of the RBT micro collection tube and the conventional sample tube on the sampler are positioned differently, and incorrect installation may result in sampling failure or sample drop.

Common faults and troubleshooting strategies

1. Sampling and barcode anomalies. If barcode reading fails, first check the label position. The XN-530 barcode label should be affixed within the designated area, and the barcode strip should be horizontal without excessive attachment, wrinkling, exceeding the bottom of the tube, or using a reusable cap. Check if the barcode type is within the supported range, such as ITF, CODABAR/NW7, CODE39, JAN/EAN/UPC, ISBT128, CODE128. If using a checksum, it should be confirmed that the setting is correct. The metal parts of the sampling adapter must be installed according to the type of sample tube and cannot be disassembled or reinstalled at will, otherwise it may become loose due to the expansion of screw holes.

2. Hole blockage, bubbles, and sampling noise. In the service data, the RBC/PLT page can view sampling data, particle counts of RBC and PLT, differences between maximum and minimum values, Clog and Bubble values. If the hole is blocked or the bubble value is abnormal, the cleaning procedure should be performed, using CELLCLEAN AUTO to clean the pipeline. Avoid generating bubbles during reagent connection, as bubbles can cause abnormal analysis. If the reagent is contaminated, turbid, or discolored, it should be replaced. When maintaining areas such as the RBC detector cover, air pump unit, and pneumatic capture chamber, power should be turned off and attention should be paid to the high temperature on the surface of the air pump.

3. Abnormal results and interference. Pseudo low WBC can be seen in white blood cell aggregation; Pseudo elevated levels can be seen in platelet aggregation, hemolysis, nucleated red blood cells, red blood cell aggregation, cold agglutinin, chyle, cold protein, cold globulin, fibrin, giant platelets, etc. Pseudo low RBC can be seen in red blood cell aggregation, small red blood cells, and red blood cell debris; Pseudo elevated levels can be seen in leukocytosis greater than 100000/μ L and giant platelets. Pseudo elevated HGB can be seen in significantly increased white blood cells, lipid levels, and abnormal proteins. Pseudo low HCT can be seen in cold agglutination, small red blood cells, and red blood cell fragments; Pseudo high can be seen in leukocytosis, severe diabetes, uremia, spherocytosis. Pseudo low PLT can be seen in platelet aggregation, pseudo thrombocytopenia, and giant platelets; Pseudo elevated levels can be seen in small red blood cells, red blood cell fragments, white blood cell fragments, cold proteins, and cold globulins. Research on interfering substances shows that bilirubin C, bilirubin F, hemolysis, fat emulsion, and chyle have concentration thresholds that affect WBC, RBC, HGB, HCT, and PLT. If the threshold is exceeded, they should be treated as interference.