Comparison of Thromboelastography Devices TEG®6S Point of Care Device vs. TEG®5000 in Pediatric Patients Undergoing Cardiac Surgery.

Thromboelastography (TEG) can predict bleeding in pediatric patients undergoing cardiac surgery. We hypothesized that results obtained from TEG®5000 correlate with the new point-of-care TEG®6S system and that TEG®6S rewarming maximum amplitude (MA) is associated with surrogate endpoints for perioperative bleeding in pediatric patients who underwent complex cardiac surgery. We describe a retrospective study of pediatric (≤18 years) patients who underwent complex cardiac surgery on cardiopulmonary bypass. Citrate whole-blood samples were used to compared TEG®5000 vs.TEG®6S and TEG®6S-FLEV (with fibrinogen measurement) vs. Clauss-fibrinogen methods. TEG®6S parameters obtained during rewarming were compared to the surrogate endpoints for perioperative bleeding using linear regression analysis. Among 100 patients, 225 TEG®5000 vs.TEG®6S comparisons and 54 TEG®6S-FLEV were analyzed. Good correlation was observed for all parameters comparing TEG®5000 to TEG®6S and TEG®6S-FLEV to the Clauss-fibrinogen method (Pearson r ≥ .7). Similar to rewarming TEG®5000 MA, rewarming TEG®6S MA was the only parameter independently associated with risk for perioperative bleeding (median [interquartile range {IQR}] in bleeding vs. nonbleeding patients: 35 [29, 48] vs. 37 [32, 55]; p = .02). A platelet transfusion calculator was developed based on TEG®6S results by determining the relationship between platelet transfusion volume (mL/kg) and percent change in MA using linear regression analysis. TEG®6S is a good alternative point-of-care method to analyze a patient's coagulation profile and it is comparable to TEG®5000 in pediatric patients undergoing cardiac surgery on cardiopulmonary bypass. Lower TEG®6S MA during rewarming is associated with increased risk for perioperative bleeding. TEG analysis during rewarming may be useful in customizing platelet transfusion therapy by reducing the risk of bleeding while minimizing excessive blood product transfusions.

Thromboelastography During Rewarming for Management of Pediatric Cardiac Surgery Patients.

BACKGROUND: Thromboelastography (TEG) predicts bleeding in pediatric patients undergoing cardiac surgical procedure. We hypothesize that TEG indicators at rewarming correlate with postprotamine values and that rewarming TEG is associated with surrogate end points for postoperative bleeding in pediatric patients undergoing complex cardiac surgical procedure. METHODS: In a retrospective study of 703 pediatric (≤18 years) patients undergoing complex cardiac surgical procedures, TEG results obtained during rewarming and after protamine administration were compared using linear regression. A composite end point of extended blood product transfusion or surgical reexploration for bleeding was used as a surrogate for postoperative bleeding. RESULTS: By multivariable analysis, longer cardiopulmonary bypass time and lower TEG maximal amplitude (MA) during rewarming were independently associated with the risk of the composite end point in the operating room or in the intensive care unit (P < .05). Among patients with an MA of less than 45 mm during rewarming, those who received a platelet transfusion in the operating room compared with those who did not were less likely to reach the composite end point within the subsequent 24 hours (8% vs 32%, respectively; P < .01). Good correlation was observed between TEG variables at rewarming vs after protamine administration (Pearson r ≥ 0.7). The relationship between platelet transfusion volume (mL/kg) and the percentage change in the MA was determined using linear regression, and a platelet transfusion calculator was generated. CONCLUSIONS: A lower MA during rewarming is associated with an increased risk of perioperative bleeding. In patients with a rewarming MA of less than 45 mm, an intraoperative platelet transfusion may reduce the risk of subsequent bleeding. Individualized platelet transfusion therapy based on rewarming TEG may reduce the risk of bleeding while minimizing unnecessary platelet transfusion.