Intraoperative Thromboelastography-activated Clotting Time After Weaning From Cardiopulmonary Bypass Correlates With Fibrinogen Concentration, and Its Prolongation May Predict Hypofibrinogenemia.

OBJECTIVES

To investigate the clinical significance of thromboelastography-activated clotting time (T-ACT) measured after weaning from cardiopulmonary bypass (CPB), particularly its potential to predict the need for blood transfusion and guide transfusion strategies in pediatric cardiac surgery.

DESIGN

Retrospective observational study.

SETTING

A single tertiary university hospital operating room.

PARTICIPANTS

218 pediatric patients aged <7 years scheduled for elective cardiac surgery using CPB.

MEASUREMENTS AND MAIN

RESULTS

After weaning from CPB and protamine administration, thromboelastography analysis and laboratory tests (including coagulation and blood count tests) were performed. Univariate analysis using the Spearman rank correlation coefficient was employed to evaluate associations between T-ACT and intraoperative patient and surgical variables measured after weaning from CPB. T-ACT showed negative correlations with platelet count, fibrinogen levels, prothrombin time, citrated rapid thromboelastography maximum amplitude, and citrated functional fibrinogen maximum amplitude. Multivariate regression using the forced-entry method included variables with p < 0.10 in the univariate analyses. The fibrinogen level, prothrombin time, and citrated functional fibrinogen maximum amplitude were statistically significant (p < 0.05). Hypofibrinogenemia detection was identified as particularly important for predicting coagulation disorders after weaning from CPB. Receiver operating characteristic analysis of T-ACT for discriminating intraoperative fibrinogen ≤150 mg/dL yielded a cutoff value of 158.1 seconds (area under the curve: 0.84; p < 0.0001).

CONCLUSIONS

In pediatric patients undergoing cardiac surgery with CPB, intraoperative T-ACT measured after weaning from CPB correlated with fibrinogen concentration, and T-ACT prolongation may discriminate hypofibrinogenemia.