Intra- and inter-centre standardisation of thromboelastography (TEG®)

Area of Science:

• Clinical Pathology
• Hematology
• Medical Device Evaluation

Background:

• Thromboelastography (TEG) is crucial for peri-operative coagulation assessment and blood product guidance.
• The UK lacks standardized TEG methods and quality assurance protocols.
• Variability in TEG results can affect clinical decision-making and patient outcomes.

Purpose of the Study:

• To investigate the reproducibility of thromboelastography (TEG) in whole blood samples.
• To identify sources of variability in TEG measurements.
• To inform the development of standardized TEG protocols.

Main Methods:

• Whole blood samples without coagulation abnormalities were tested in three phases.
• Assays were performed by a single operator, multiple operators at one location, and across multiple locations after sample transport.
• Reproducibility of R-time, K-time, and maximum amplitude was assessed against a tolerance range (median ± 20%).

Main Results:

• Significant variability was observed in R-time (21%) and K-time (25%) measurements.
• Operator and location differences contributed to result variability.
• Maximum amplitude demonstrated good reproducibility across all testing phases.
• Analysis from the same kaolin vial showed less variation than from different vials.

Conclusions:

• Thromboelastography R- and K-times exhibit high variability, potentially due to inconsistent blood-kaolin mixing.
• Maximum amplitude reproducibility is good, offering a stable parameter.
• Further research is needed, especially in coagulopathic patients, to refine TEG standardization and transfusion practices.