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Comparison between thromboelastography and conventional coagulation tests after cardiopulmonary bypass surgery in the
J Pekelharing1, A Furck, W Banya
1Department of Paediatric Cardiac Intensive Care, Royal Brompton Hospital & Harefield NHS Foundation Trust, London, UK.
Insights
Routine coagulation tests, particularly fibrinogen levels, better predict postoperative bleeding in children after heart surgery than thromboelastography (TEG). TEG's maximum amplitude correlated with platelet count and fibrinogen.
Area of Science:
- Pediatric Cardiac Surgery
- Coagulation Science
- Critical Care Medicine
Background:
- Postoperative bleeding is a significant risk following pediatric cardiac surgery with cardiopulmonary bypass (CPB).
- Risk factors include patient age, surgical complexity, and coagulopathy due to dilution and consumption of clotting factors.
Purpose of the Study:
- To compare the effectiveness of thromboelastography (TEG) versus routine laboratory coagulation assays in assessing bleeding risk post-pediatric CPB.
- To determine which coagulation tests best correlate with postoperative blood loss.
Main Methods:
- A prospective audit of 107 pediatric patients admitted to the pediatric intensive care unit (PICU) post-CPB.
- Coagulation tests included fibrinogen, prothrombin time, activated partial thromboplastin time (APTT), full blood count, and TEG.
- Bleeding was quantified by chest drain output within the first 1-4 hours, with significant bleeding defined as ≥5 ml/kg/h.
Main Results:
- Fibrinogen concentration showed the strongest correlation with first-hour blood loss (r(s) = 0.52), followed by APTT (r(s) = 0.44) and TEG maximum amplitude (MA) (r(s) = 0.34).
- TEG MA demonstrated good correlation with platelet count (r(s) = 0.68) and fibrinogen levels (r(s) = 0.66).
- 23 out of 107 patients experienced significant bleeding in the first hour.
Conclusions:
- Thromboelastography did not provide a better correlation with postoperative bleeding compared to conventional coagulation tests.
- TEG's maximum amplitude is a useful indicator of platelet count and fibrinogen levels, but not superior for predicting overall bleeding risk.
Introduction:
Following paediatric cardiac surgery using cardiopulmonary bypass (CPB), there is a risk of significant postoperative bleeding. A number of risk factors are associated with postoperative bleeding including; age, complexity of the surgery, dilution and consumption of clotting factors. We conducted a prospective audit comparing different coagulation tests used following paediatric CPB to determine whether thromboelastography (TEG) on the intensive care unit or routine laboratory coagulation assays including fibrinogen are better at assessing bleeding and bleeding risk.
Methods:
Tests on arrival in paediatric intensive care unit (PICU) included the following: fibrinogen, prothrombin time, activated partial thromboplastin time, full blood count and TEG. Bleeding was measured in the first 1-4 h via chest drain loss. Bleeding was considered significant if ≥5 ml/kg/h.
Results:
Of 107 patients admitted to PICU, 23/107 were considered to be bleeding during the first hour. Fibrinogen concentration had the best correlation with the amount of first-hour blood loss (r(s) = 0.52), followed by APTT (r(s) = 0.44) and TEG MA (r(s) = 0.34). TEG parameter TEG MA correlated with platelet count (r(s) = 0.68) and fibrinogen (r(s) = 0.66).
Conclusions:
Thromboelastography did not show better correlation with postoperative bleeding than conventional clotting tests. TEG parameter maximum amplitude correlates with platelet count and fibrinogen.
