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Hematology

Continuous Quality Improvement

Quality in the clinical laboratory is not a static destination but a dynamic process. Continuous Quality Improvement (CQI) represents the overarching managerial philosophy that focuses on the systematic improvement of processes to maximize patient safety and operational efficiency. While Quality Control (QC) detects immediate errors in an analytical run, and Quality Assurance (QA) monitors the overall outcome, CQI proactively seeks to identify the root causes of potential errors and eliminate them before they occur. It shifts the culture from “blaming individuals” to “improving systems”

The Quality Management System (QMS)

CQI operates within the framework of a Quality Management System. The Clinical and Laboratory Standards Institute (CLSI) defines this framework through the 12 Quality System Essentials (QSEs). These essentials (which include Personnel, Equipment, Process Control, Documents/Records, etc.) cover every aspect of the laboratory’s path of workflow

The Path of Workflow

To implement CQI effectively, the laboratory is divided into three distinct phases of testing. Errors can occur in any phase, but studies consistently show that the majority of errors occur in the Pre-Analytical phase

  • Pre-Analytical Phase (Specimen Collection and Transport): This phase encompasses everything that happens before the sample touches the analyzer
    • CQI Focus: Reducing patient misidentification errors, minimizing clotted CBCs (improper mixing), reducing hemolyzed coagulation samples (traumatic draw), and improving turnaround time (TAT) for transport
  • Analytical Phase (Testing): The actual analysis of the specimen
    • CQI Focus: Optimizing instrument precision (CV%), reducing random and systematic errors through Westgard rule application, and minimizing instrument downtime through preventative maintenance
  • Post-Analytical Phase (Reporting): The transmission of data to the clinician
    • CQI Focus: Ensuring critical values are called and documented within time limits, reducing corrected reports (data entry errors), and ensuring LIS interface reliability

Methodologies for Improvement

Laboratories borrow heavily from industrial manufacturing philosophies (like Toyota and Motorola) to drive improvement. The most common methodologies utilized in Hematology are Lean, Six Sigma, and the PDCA cycle

The PDCA Cycle (Deming Cycle)

This is the fundamental model for ongoing improvement. It is a four-step iterative process used to solve problems:

  • Plan: Identify a problem (e.g., “ED Stat CBC turnaround time is too long”) and propose a solution (e.g., “Install a pneumatic tube station directly to Hematology”). Establish a baseline metric
  • Do: Implement the solution on a small scale or trial basis
  • Check: Measure the results. Did the TAT improve? Did the new tube system cause hemolysis (a new problem)? Compare the new data to the baseline
  • Act: If the plan worked, standardize the change (update SOPs, train all staff). If it failed, adjust the plan and start the cycle again

Lean (Waste Reduction)

Lean methodology focuses on identifying and eliminating “Waste” (Non-Value-Added activities) to improve speed and flow

  • The 7 Wastes in the Lab
    1. Waiting: Techs waiting for the centrifuge to finish
    2. Motion: Excessive walking because the slide stainer is on the other side of the room from the microscope
    3. Transport: Moving samples unnecessarily between benches
    4. Overproduction: Printing reports that no one reads
    5. Inventory: Stocking expired reagents (waste of money and space)
    6. Defects: Hemolyzed samples that must be redrawn
    7. Over-processing: Repeating a test that didn’t need to be repeated
  • 5S Tool: A Lean tool for organizing the workspace: Sort (remove clutter), Set in Order (a place for everything), Shine (clean), Standardize (make it the rule), and Sustain (keep doing it)

Six Sigma (Defect Reduction)

Six Sigma focuses on minimizing Variation. The goal is to reduce process variation so that virtually all products (test results) meet the specifications (are error-free)

  • Sigma Metric: A statistical calculation of performance
    • 6 Sigma: World-class performance (3.4 defects per million opportunities)
    • 3 Sigma: Minimum acceptable performance for a clinical lab
  • DMAIC Process: The roadmap for Six Sigma projects: Define the problem, Measure the current state, Analyze the root cause, Improve the process, and Control the new process to prevent backsliding

Key Performance Indicators (KPIs)

To improve quality, you must measure it. KPIs (or Quality Indicators) are specific metrics tracked over time to monitor the health of the laboratory’s operations. The lab director sets “Thresholds” for acceptability

  • Turnaround Time (TAT): The most visible KPI
    • Metric: % of ER CBCs completed within 30 minutes
    • Target: > 90%
  • Specimen Rejection Rate
    • Metric: % of samples rejected due to hemolysis or clotting
    • Target: < 1% of total collection volume
  • Corrected Reports
    • Metric: The number of times a result was released and then changed later
    • Significance: A high number indicates a failure in the Verification process or LIS interface issues
  • Blood Culture Contamination
    • Metric: % of blood cultures growing skin flora (e.g., Staph epidermidis)
    • Target: < 3%. This measures phlebotomy aseptic technique
  • Critical Value Reporting
    • Metric: % of critical values communicated within the mandated window (usually 15-30 mins)

Root Cause Analysis (RCA)

When a significant error or “Sentinel Event” occurs (e.g., a patient is transfused based on a misidentified specimen), the laboratory performs an RCA. The goal is not to punish the employee but to find the systemic failure

  • The “5 Whys”: A technique where the manager asks “Why?” five times to drill down to the root
    • Example: Specimen was mislabeled. Why? The nurse labeled it at the desk. Why? The computer in the room was broken. Why? IT hasn’t fixed it. Root Cause: IT support failure and lack of bedside label printers
  • Fishbone Diagram (Ishikawa): A visual tool that categorizes causes into:
    • Man: Personnel training, fatigue, staffing levels
    • Machine: Analyzer malfunction, calibration drift
    • Method: SOPs, policies, workflow
    • Material: Reagents, tube quality
    • Environment: Lighting, noise, temperature

Proficiency Testing (PT) as CQI

External Proficiency Testing (e.g., CAP Surveys) is a major component of CQI. It compares the laboratory’s accuracy against a peer group of thousands of other laboratories

  • Benchmarking: If the lab’s result for Hemoglobin is 13.0, and the peer group mean is 13.1, the lab knows its accuracy is excellent. If the peer group mean is 14.5, the lab has a significant Bias
  • Investigation: Any PT failure (< 80% score) requires a documented investigation. This often reveals shifting calibration or reagent deterioration that daily QC missed. This allows the lab to correct the issue before it affects patient care

The Cost of Quality (CoQ)

CQI also manages the financial impact of quality. Money spent on quality is categorized into three buckets:

  • Prevention Costs: Money spent to prevent errors (Training, preventative maintenance, safety features). This is “Good” spending
  • Appraisal Costs: Money spent to check for errors (Running QC, Proficiency Testing, Inspection fees). This is necessary spending
  • Failure Costs: Money lost due to errors (Discarded reagents, re-running tests, lawsuits, lost accreditation). This is “Bad” spending. The goal of CQI is to increase Prevention costs to drastically reduce Failure costs