Fast interpretation of thromboelastometry in non-cardiac surgery: Reliability in patients with hypo-, normo-, and hypercoagulability

Abstract

BackgroundConventional coagulation test are not useful to guide haemostatic therapy in severe bleeding due to their long turn-around time. In contrast, early variables assessed by point-of-care thromboelastometry (ROTEM ®) are available within 10-20 min and increasingly used to guide haemostatic therapy in liver transplantation and severe trauma. However, the reliability of early ROTEM® variables to predict maximum clot firmness (MCF) in non-cardiac surgery patients with subnormal, normal, and supranormal MCF has not yet been evaluated.MethodsRetrospective data of 14 162 ROTEM® assays (3939 EXTEM®, 3654 INTEM ®, 3287 FIBTEM®, and 3282 APTEM® assays) of patients undergoing non-cardiac surgery were analysed. ROTEM ® variables [clotting time (CT), clot formation time (CFT), angle, A5, A10, and A15] were related to MCF by linear or non-linear regression, as appropriate. The Bland-Altman analyses to assess the bias between early ROTEM® variables and MCF and receiver operating characteristics (ROC) were also performed.ResultsTaking the best and worst correlation coefficients for each assay type, CT (r=0.18-0.49) showed the worst correlation to MCF. In contrast, angle (r=0.85-0.88) and CFT (r=0.89-0.92) demonstrated good but non-linear correlation with MCF. The best and linear correlations were found for A5 (r=0.93-0.95), A10 (r=0.96), and A15 (r=0.97-0.98). ROC analyses provided excellent area under the curve (AUC) values for A5, A10, and A15 (AUC=0.962-0.985).ConclusionsEarly values of clot firmness allow for fast and reliable prediction of ROTEM® MCF in non-cardiac patients with subnormal, normal, and supranormal MCF values and therefore can be used to guide haemostatic therapy in severe bleeding. © 2012 © The Author [2012]. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved.