Does incorporation of thromboelastography improve bleeding prediction following adult cardiac surgery?
Cardiopulmonary bypass (CPB) coagulopathy increases utilization of allogenic blood/blood products, which can negatively affect patient outcomes. Thromboelastography (TEG) is a point-of-care measurement of clot formation and fibrinolysis. We investigated whether the addition of TEG parameters to a clinically based bleeding model would improve the predictability of postoperative bleeding. A total of 439 patients' charts were retrospectively investigated for 8-h chest tube output (CTO) postoperatively. For model 1, the variables recorded were patient age, gender, body surface area, clopidogrel use, CPB time, first post-CPB fibrinogen serum level, first post-CPB platelet count, first post-CPB international normalized ratio, the total amount of intraoperative cell saver blood transfused, and postoperative first ICU hematocrit level. Model 2 had the model 1 variables, TEG angle, and maximum amplitude. The outcome was defined as 0-8-h CTO. The predictor variables were placed into a forward stepwise regression model for continuous outcomes. Analysis of variance with adjusted R was used to assess the goodness-of-fit of both predictive models. The predictive accuracy of the model was examined using CTO as a dichotomous variable (75th percentile, 480 ml) and receiver operating characteristic curves for both models. Advanced age, male gender, preoperative clopidogrel use for 5 days or less, greater cell saver blood utilization, and lower postoperative hematocrit levels were associated with increased 8-h CTO (P < 0.05). Adding TEG angle and maximum amplitude to model 1 did not improve CTO predictability. When TEG angle and maximum amplitude were added as predictor factors, the predictability of the bleeding model did not improve.
aDepartment of Cardiac Anesthesia/Cardiac Surgery, St Vincent's Hospital Heart Center, Green Bay, Wisconsin bDepartment of Pharmaceutical Sciences, Campbell University, Buies Creek, North Carolina, USA.
Ajeet D
AD
Sharma
Antoine
A
Al-Achi
John F
JF
Seccombe
Richard
R
Hummel
Matt
M
Preston
Dana
D
Behrend
D000367:Age Factors; D000368:Aged; D001792:Blood Platelets / Q000378:metabolism / Q000473:pathology*; D002315:Cardiopulmonary Bypass / Q000009:adverse effects*; D015505:Chest Tubes; D000077144:Clopidogrel; D005260:Female; D005340:Fibrinogen / Q000378:metabolism; D006400:Hematocrit; D006801:Humans; D019934:International Normalized Ratio; D008297:Male; D008875:Middle Aged; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use; D010976:Platelet Count; D019095:Point-of-Care Systems; D019106:Postoperative Hemorrhage / Q000097:blood / Q000175:diagnosis* / Q000209:etiology; D011237:Predictive Value of Tests; D012372:ROC Curve; D012189:Retrospective Studies; D012737:Sex Factors; D013916:Thrombelastography; D013988:Ticlopidine / Q000031:analogs & derivatives / Q000627:therapeutic use
D010975:Platelet Aggregation Inhibitors; D005340:Fibrinogen; D000077144:Clopidogrel; D013988:Ticlopidine