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• Platelet Function Test

  • Platelet Aggregometers
  • Platelet function Analyzers
  • Flow Cytometry
  • Molecular Technologies for the coagulation Laboratory
  • Future Technologies for the Coagulation Laboratory
  • Current Available Coaguation Instruments
• Automation not foolproof
• Evolution of Coagulation Laboratory

  • Historical Perspective of Clot Assessment
  • Assay End-Point Detection Principles
  • Mechanical Clot End-Point Detection
  • Photo-Optical Clot End-Point Detection
  • Viscoelastic Clot Detection
  • Chromogenic End-Point Detection
  • Nephelometric End-Point Detection
  • Immunologic Light Absorbance End-Point Detection
  • Advantages and Disadvantages of Detection Methods
• Automation Advancemen
• Introduction of New Instrumentation

  1. Expansion of coagulation testing capabilities

  2. Formerly specialized tests now accessible to general med.lab staff
• Requires expertise in result interpretation and correlation with patient diagnosis
• Current Challenges
• Coagulation Instrumentation and Technology Advancements


  • Improved Accuracy and Precision
  • Random Access Testing
  • Improved Reagent Handling
  • Improved Specimen Management
  • Expanded Computer Capabilities
  • Quality Features of Automated Assay Performance
  • Specimen Quality Set Points
  • Selection of Coagulation Instrumentation
  • Point of Care Coagulation Testing
  • Global Hemostasis Assessment
• Specialized Testing

  • Limited to tertiary care institutions
  • Required specialized training for medical laboratory scientist
• Cognitive Abilities in Coagulation Testing

  • Understanding the complexities of hemostatic mechanisms
  • Interpreting critical test results accurately
• Importance of Method Validation

  • Ensuring accuracy and validity of test results
  • Crucial for informed decision-making in patient care
• Continued advancements in automation and instrumentation
• Application and Benefits of Chromogenic Assay

  1. Measure specific coagulation factors' activity

  2. Assess inhibitors and quantitate substances like heparin

  3. High specificity and sensitivity

  4. Quantitative assessment of coagulation factors

  5. Enables precise diagnosis and monitoring of coagulation disorders
• Viscoelastic Instrumentation

  1. Remains vital for assessing hemostasis

  2. Detailed analysis of clotting dynamics and properties

  3. Offers insights into coagulation disorders and thrombotic conditions
• Technological Advancements

  1. Transition to Photo-Optical Detection

  2. Integration of Viscoelastic End-Point Detection for Specialty Testing

  3. Integration of Multiple End-Point Mechanisms

  4. Incorporation of Chromogenic and Immunoassay-Based Testing

  5. Streamlining Laboratory Workflows for Routine and Specialized Testing Needs
• Observation-Based End-Point Detection

  1. Utilizes "Observation" of Clot Formation

  2. Commonly Used in Traditional Coagulation Instruments
• Future Trends
• Role of Medical Laboratory Scientists

  • Key players in maintaining quality and reliability of coagulation testing
  • Expertise in method validation and result interpretation
• Automation Advancement

  1. Standardization of testing processes

  2. Increased consistency and cost-effectiveness
• Integration of molecular and genetic testing in coagulation assessment
• Chromogenic Assay Examples

  Measure the activity of coagulation enzymes through direct or indirect chromogenic methods
• Overview of Photo-Optical Clot End-Point Detection

  1. Photo-optical (turbidometric) coagulometers detect changes in plasma optical density (OD) during clotting

  2. Provides information on various aspects of the clotting process: Time to clot, Kinetics of whole blood clot formation, Clot strength, Fibrinolytic activity
• Nephelometry Assay

  1. As fibrin polymers form, side scatter and forward-angle scatter increase

  2. Timer stops when scatter reaches predetermined intensity, recording time to clot interval

  3. Nephelometry adapted to measure dynamics or kinetics of clot formation

  4. Continuous readings throughout clotting per
• Feel-Based End-Point Detection

  1. Detects Clot Formation by "Feel"

  2. Early Instruments Primarily Relied on Mechanical Principles
• Advantages and Applications of Immunoassay technology on coagulometers
• Nephelometry Assay

  1. As fibrin polymers form, side scatter and forward-angle scatter increase

  2. Timer stops when scatter reaches predetermined intensity, recording time to clot interval

  3. Nephelometry adapted to measure dynamics or kinetics of clot formation

  4. Continuous readings throughout clotting period produce clot curve or "signature"

  5. Originally applied to immunoassays, still used today to detect antigen-antibody complexes

  6. Precipitation of immune complexes results in turbidity, scattering incident light
• Random Access Testing in automated coagulometers
• Coagulation Instrumentation and Technology Advancements
• Open Reagent Systems in coagulation instrumentation
• Improved Specimen Management in coagulation instrumentation
• Enhanced Computer Capabilities in Coagulation Analyzers
• Immunologic Light Absorbance End-Point Detection

  1. Clot-Based Assays and Immunoassays on One Platform

  2. Integration of clot-based assays and immunoassays on a single platform enhances coagulation testing efficiency and versatility

  3. A newer method for immunoassays in routine coagulation testing

  4. Latex microparticles coated with antibodies react with antigens, forming agglutinates that absorb light, proportional to antigen levels
• Advantages and Disadvantages of Detection Methods
• Improved Accuracy and Precision in coagulation instrumentation
• Automatic Dilutions in coagulation instrumentation
• Improved Reagent Handling in coagulation instrumentation
• Reagent Tracking in coagulation instrumentation
• Global Hemostasis Assessment

  ROTEM (Rotational Thromboelastometry) is a newer version of thromboelastography, Enhancements include: Not sensitive to vibrations, Four test channels, Touch screen interface, Automated pipettor, Similar to TEG, assesses clot formation and fibrinolysis using whole blood and various coagulation activators, ROTEM clot signature comparable to TEG, Reagents available for several coagulation assays, Results available within 10 to 20 minutes, Operator dependent and requires training and skill for accurate interpretation
• Quality Features of Automated Assay Performance


  • Improved flagging capabilities for instrument performance and specimen quality
  • Reflex testing based on preset parameters or prior test results
  • Kinetics of clot formation graphing for enhanced analysis and troubleshooting
• Selection of Coagulation Instrumentation

  1. Considerations for cost-effectiveness, testing capabilities, and standardization

  2. Identify testing needs based on patient population

  3. Collaboration with medical staff for test appropriateness

  4. Match instrument to anticipated workload

  5. Consider sending out esoteric or low-volume tests to reference laboratories

  6. Throughput of routine coagulation tests

  7. Additional features prioritization

  8. Specialized features consideration for advantageous capabilities