Rapid and Correct Prediction of Thrombocytopenia and Hypofibrinogenemia With Rotational Thromboelastometry in Cardiac Surgery

Objectives: In the present study, the authors have investigated whether rotational thromboelastometry (ROTEM) could predict thrombocytopenia and hypofibrinogenemia in cardiac surgery using the clot amplitude after 5 minutes (A5). Another parameter, PLTEM, in which the contribution of fibrinogen is eliminated by subtracting a fibrin-specific ROTEM test (FIBTEM) from an extrinsically-activated ROTEM test (EXTEM), was investigated. Furthermore, the turnaround time of ROTEM was compared to conventional laboratory tests.Design: Prospective cohort study.Setting: Single academic medical center.Participants: Ninety-seven patients undergoing cardiac surgery between July 2011 until August 2012.Interventions: The correlations between EXTEM/FIBTEM A5, A10, and maximal clot formation (MCF), EXTEM/PLTEM (A5/A10, and MCF) and platelet count, and FIBTEM (A5/A10, and MCF) and fibrinogen were evaluated using the Pearson's correlation coefficient and receiver-operating characteristic curves. Turnaround times of ROTEM tests and conventional laboratory tests were assessed in the central laboratory.Measurements and Main Results: EXTEM AS and FIBTEM A5 showed an excellent correlation with A10 (R:0.99/1.00) and MCF (R:0.97/0.99). The correlation between EXTEM AS and platelet count (R:0.74) was comparable with the correlation of A10 (R:0.73) and MCF (R:0.70) with platelet count. FIBTEM AS predicted fibrinogen levels (R:0.87) as well as A10 (R:0.86) and MCF (R:0.87). PLTEM AS (R:0.85) correlated better with platelet count than EXTEM A5 (R:0.74; p = 0.04) and showed significantly better area under the curve values than EXTEM for predicting thrombocytopenia (A5 p = 0.012, A10 p = 0.019). Turnaround time for ROTEM tests, 12 minutes, was comparable with emergency requests for platelet count, 13 minutes, and shorter than emergency requests for fibrinogen levels, 37 minutes.Conclusions: Implementation of PLTEM and FIBTEM AS in ROTEM-guided transfusion protocols may improve transfusion management.