An alternate method for calibrating the thromboelastograph.
OBJECTIVE: This study evaluated various substances that could be used to calibrate the Thrombelastograph. DESIGN: Prospective, controlled comparison. SETTING: Operating room laboratory at a tertiary care university hospital. PARTICIPANTS: None. INTERVENTIONS: Six substances commonly available in the operating room setting (ointments, creams, and gels) were analyzed by thromboelastography for 3 minutes. Sixty measurements were made for each substance. MEASUREMENTS AND MAIN RESULTS: Thromboelastographic analysis of the ointments and cream preparations had an amplitude variability that exceeded 10 mm within the 3-minute recording period. The conductive gel had the most reproducible thromboelastography tracing with a mean amplitude of 62.5 +/- 1.1 mm (analysis of variance, p < 0.0005). There was a significant correlation between the reported viscosity of the three gels and the deflection amplitude (linear regression, R2 = 0.97; p < 0.0001). CONCLUSION: Conductive gel is a useful substance for quickly checking the functional status of the Thrombelastograph at an operational stage. Calibration of the Thrombelastograph using a gel of known viscosity is clinically relevant and may be more practical than testing with thromboelastographic-defined normal and abnormal blood analogs.