Standard Operating Procedure: Hematology Laboratory Operations

This document outlines the mandatory procedures for the operation of the Hematology Laboratory, ensuring the accuracy, reliability, and safety of patient blood analysis. Adherence to these protocols is critical to maintaining high-quality diagnostic standards, minimizing pre-analytical errors, and ensuring compliance with regulatory bodies. All laboratory personnel must review this document annually and demonstrate competency in the procedures described herein.

1. Pre-Analytical Phase: Specimen Handling and Verification

• Verify patient identity against the laboratory request form using at least two unique identifiers (e.g., full name and Date of Birth).
• Inspect specimen integrity: Ensure tubes are correctly labeled, not expired, and free of clots or hemolysis.
• Confirm correct tube selection (typically Lavender-top K2/K3 EDTA).
• Ensure the sample volume is adequate and reaches the fill-line to prevent improper anticoagulant-to-blood ratio.
• Perform visual inspection for lipemia, icterus, or gross hemolysis before entry into the analyzer.
• Log the specimen into the Laboratory Information System (LIS) immediately upon receipt.

2. Analytical Phase: Instrument Calibration and Quality Control (QC)

• Perform daily startup sequences as defined by the manufacturer’s instructions.
• Run Low, Normal, and High levels of Quality Control (QC) material.
• Verify that all QC results fall within the established ±2 Standard Deviation (SD) range on Levey-Jennings charts.
• Do not process patient samples if QC fails; troubleshoot, re-run, and escalate to the laboratory supervisor if necessary.
• Ensure reagents are within their shelf-life and volume levels are sufficient for the expected daily workload.
• Perform background checks on the analyzer to ensure the count is within acceptable "blank" limits.

3. Post-Analytical Phase: Result Review and Reporting

• Review all automated flagging (e.g., nucleated RBCs, platelet clumps, or abnormal white cell distributions).
• Perform peripheral blood smear review for any samples triggering reflex criteria (e.g., abnormal morphology, immature cells, or instrument flags).
• Confirm that Critical Values (e.g., extreme hemoglobin or platelet levels) are reported via direct telephone notification to the ordering clinician.
• Validate and release results in the LIS after ensuring all delta checks and automated edits are satisfied.
• Document any discrepancies or manual adjustments made to the automated results.

4. Safety and Maintenance

• Wear appropriate Personal Protective Equipment (PPE) at all times: fluid-resistant lab coat, gloves, and safety goggles.
• Dispose of all biological waste in designated biohazard containers.
• Perform the scheduled end-of-day instrument shutdown/cleaning cycle.
• Sanitize workstations with an approved 10% bleach solution or laboratory-grade disinfectant at the end of each shift.

Pro Tips & Pitfalls

• Pitfall: Clotted Samples. Never run a sample if clots are suspected. This can cause instrument aspiration probe failure or false-low platelet counts. Always invert samples gently 8–10 times immediately before analysis.
• Pro Tip: Delta Checks. Use the LIS delta check function as your first line of defense. A drastic change in an individual’s hemoglobin or MCV between visits is often the first indicator of sample mislabeling.
• Pitfall: Hemolysis/Lipemia. Recognize that severe lipemia can falsely elevate Hemoglobin results. When in doubt, utilize plasma replacement protocols to clear the sample.
• Pro Tip: Slide Staining. Maintain clean, filtered staining solutions. Precipitated stain deposits are frequently mistaken for pathogens or abnormal inclusions under the microscope.

Frequently Asked Questions (FAQ)

Q: What should I do if the daily QC is outside the acceptable range? A: Do not report patient results. Check for expired controls, re-mix the control vials, and perform a maintenance cycle (e.g., probe clean). If the problem persists, escalate to the supervisor and consider recalibrating the instrument.

Q: Why is it necessary to manually review peripheral blood smears? A: Automated analyzers are excellent at counting but struggle with morphological nuances. Manual review is essential for detecting specific pathological features like schistocytes, blast cells, or reactive lymphocytes that are clinically significant.

Q: How long should clinical blood samples be retained? A: Retain samples in the refrigerated storage area (2°C–8°C) for at least 48 to 72 hours post-analysis, or as dictated by your specific hospital policy, to allow for add-on testing or result verification.