Substitution of ROTEM FIBTEM A5 for A10 in trauma: an observational study building a case for more rapid analysis of coagulopathy.

Abstract

Rotational thromboelastometry (ROTEM®) allows guided blood product resuscitation to correct trauma-induced coagulopathy in bleeding trauma patients. FIBTEM amplitude at 10min (A10) has been widely used to identify hypofibrinogenaemia; locally a threshold of < 11mm has guided fibrinogen replacement. Amplitude at 5min (A5) carries an inherent time advantage. The primary aim was to explore the relationship between FIBTEM A5 and A10 in a trauma. Secondary aim was to investigate the use of A5 as a surrogate for A10 within a fibrinogen-replacement algorithm. Retrospective observational cohort study of arrival ROTEM results from 1539 consecutive trauma patients at a Level 1 trauma centre in Australia. Consistency of agreement between FIBTEM A5 and A10 was assessed. A new fibrinogen replacement threshold was developed for A5 using the A5-A10 bias; this was clinically compared to the existing A10 threshold. FIBTEM A5 displayed excellent consistency of agreement with A10. Intraclass correlation coefficient = 0.972 (95% confidence interval [CI] 0.969-0.974). Bias of A5 to A10 was -1.49 (95% CI 1.43-1.56) mm. 19.34% patients met the original local threshold of A10 < 11mm; 19.28% patients met the new, bias-adjusted threshold of A5 < 10mm. ROTEM FIBTEM A5 reliably predicts A10 in trauma. This further validates use of the A5 result over A10 allowing faster decision-making in time-critical resuscitation of trauma patients. A modification of -1 to the A10 threshold might be appropriate for use with the A5 value in trauma patients.