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Clot dynamics and mortality: The MA-R ratio.

Stephanie A Savage1, Ben L Zarzaur, Timothy H Pohlman

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A novel ratio using thromboelastography (TEG) values, MA-R, can predict traumatic coagulopathy risk. Lower MA-R ratios indicate higher mortality risk, suggesting potential for earlier cryoprecipitate use.

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Area of Science:

  • Trauma resuscitation
  • Coagulopathy diagnostics
  • Thromboelastography applications

Background:

  • Traumatic coagulopathy is common, characterized by rapid clot formation and fibrinogen depletion.
  • Identifying patients at risk of bleeding diathesis using traditional methods can be challenging.
  • Thromboelastography (TEG) offers insights into clot dynamics but requires novel metrics for risk stratification.

Purpose of the Study:

  • To develop a single TEG-derived value to assess the risk of traumatic coagulopathy.
  • To create a ratio reflecting both hypercoagulable and hypocoagulable states in trauma patients.
  • To evaluate the ratio's predictive value for blood product transfusion and mortality.

Main Methods:

  • Patients admitted to Level I trauma centers receiving PRBCs within 24 hours were included.
  • A novel ratio (MA-R) was calculated by dividing Maximum Amplitude (MA) by R-time from admission TEG.
  • Multivariable logistic regression analyzed the association between MA-R quartiles and mortality.

Main Results:

  • 330 patients were analyzed; the MA-R ratio was calculated from admission TEG.
  • Increasing MA-R ratios correlated with decreased odds of mortality.
  • Lowest MA-R ratios were associated with higher Injury Severity Score (ISS) and increased plasma utilization.

Conclusions:

  • The MA-R ratio effectively predicts mortality risk in trauma patients.
  • This novel metric can identify at-risk individuals early, even without other signs of derangement.
  • Low MA-R ratios may guide earlier cryoprecipitate resuscitation over traditional plasma use.