Viscoelastic measurements of coagulation provide much needed information, including guidance for triage and insight into bleeding disorders. The current clinical standards for these devices are the thromboelastogram (TEG) 5000 and the rotational thromboelastometer (ROTEM) delta, but a new product, the TEG 6s, has recently come to market, designed to simplify the user experience, reduce the required blood volume, and conduct multiple assays simultaneously. This study compares the performance of these three devices and examines the resiliency of the TEG 6s under various stresses.METHODS
The variances of coagulation metrics obtained by the TEG 6s (prototype and production models), TEG 5000, and ROTEM delta were compared using manufacturers' reagents and citrate-collected blood from healthy donors. Variability between devices was examined, and their performances under various motion and temperature stresses were compared by placing one unit on a linear or orbital shaker, in the cold, or in the heat while a counterpart remained stationary at room temperature.RESULTS
Although most comparable parameters had low degrees of variance, there were small but significantly increased variances found in some ROTEM delta and TEG 5000 parameters versus comparable TEG 6s parameters. Orbital rotation of the TEG 6s had no effect on means of any parameter but resulted in increased variance of 2 parameters, but linear motion with sudden striking had no observed impact on results. Similarly, 7-day exposure to heat (45°C) or cold (4°C) only resulted in minor deviations within normal ranges of the TEG 6s.DISCUSSION
The TEG 6s provides several improvements over other coagulation analyzers: it is easier to use and robustly resilient against motion and temperature stresses. These features suggest that it may be capable of deployment not only in the clinical laboratory but also to a variety of austere settings.LEVEL OF EVIDENCE
Diagnostic test, level III.