BN is a 2010 National Blood Foundation Grantee for the conduct of research related to coagulopathy in trauma.
Vitamin K-dependent coagulation factor deficiency in trauma: a comparative analysis between international normalized ratio and thromboelastography (CME)
Article first published online: 11 JUL 2011
© 2011 American Association of Blood Banks
Volume 52, Issue 1, pages 7–13, January 2012
How to Cite
Nascimento, B., Al Mahoos, M., Callum, J., Capone, A., Pacher, J., Tien, H. and Rizoli, S. (2012), Vitamin K-dependent coagulation factor deficiency in trauma: a comparative analysis between international normalized ratio and thromboelastography (CME). Transfusion, 52: 7–13. doi: 10.1111/j.1537-2995.2011.03237.x
Funding for the Observational Trial was provided by the Canadian Forces Health Services and Defense Research Development Canada (DRDC), Government of Canada. The study sponsor had no involvement in the study design; collection, analysis, and interpretation of data; the writing of the manuscript; or the decision to submit the manuscript for publication.
- Issue published online: 3 JAN 2012
- Article first published online: 11 JUL 2011
- Received for publication October 22, 2010; revision received April 28, 2011, and accepted April 28, 2011.
BACKGROUND: The use of international normalized ratio (INR) to diagnose vitamin K-dependent coagulation factor (VitK-CF) deficiency in trauma has limitations (inability to predict bleeding and long turnaround times). Thromboelastography (TEG) assesses the entire coagulation process. With TEG, reaction time (TEG-R) is used to assess global coagulation factor activity and takes less than 10 minutes. We assessed the ability of TEG-R to detect VitK-CF deficiency in trauma, compared to the INR.
STUDY DESIGN AND METHODS: A total of 219 trauma patients with INR, TEG, and all VitK-CF measured at admission were included. Demographics and laboratory tests, drugs, blood transfusions, and severity scores were analyzed. Specificity, sensitivity, positive predictive value (PPV), and negative predictive value (NPV) of INR (≥1.3 and ≥1.5) and TEG-R (>8 min) to diagnose VitK-CF deficits (≤50%) were calculated. Secondary outcomes included time to INR and TEG results.
RESULTS: Overall, TEG-R performed worse than INR. TEG-R had a sensitivity of 33% (95% CI, 16%-55%), specificity of 95% (95% CI, 91%-98%), PPV of 47% (95% CI, 23%-72%), and NPV of 92% (95% CI, 87%-95%). An INR of 1.5 or greater had a sensitivity of 67% (95% CI, 45%-84%), specificity of 98% (95% CI, 96%-99.7%), PPV of 84% (95% CI, 60%-97%), and NPV of 96% (95% CI, 92%-98%). An INR of 1.3 or greater also had better sensitivity, PPV, and NPV. For patients on warfarin, the times to INR results and TEG completion were 58 (±23) and 92 (±40) minutes (p = 0.07), respectively. TEG-R was abnormal in only one patient on warfarin.
CONCLUSION: Our study suggests that TEG-R is not superior at identifying VitK-CF deficiency compared to INR in trauma.