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High-molecular-weight hydroxyethyl starch accelerates kallikrein-dependent clot initiation
1Department of Anesthesiology, The University of Alabama at Birmingham, Birmingham, Alabama 35249-6810, USA. vnielsen@uab.edu
The Journal of Trauma
|June 15, 2007
Summary
Hydroxyethyl starch (HES) solutions like Hextend accelerate clot initiation by affecting kallikrein. This study investigated HES
Area of Science:
- Coagulation science
- Hemostasis research
- Biomedical engineering
Background:
- Decreased reaction time (R) on thrombelastography suggests hypercoagulability.
- Hydroxyethyl starch (HES) solutions can decrease R in celite-activated plasma.
- The effect of HES on kallikrein-dependent clot initiation requires clarification.
Purpose of the Study:
- To determine if HES solutions affect kallikrein-dependent clot initiation.
- To compare the effects of Hextend and Voluven on clot initiation.
- To investigate the role of aprotinin and prekallikrein in HES-induced changes.
Main Methods:
- Human plasma was diluted with saline, Hextend, or Voluven, with or without aprotinin.
- Thrombelastography was performed after recalcification and celite activation.
- Experiments were repeated using prekallikrein-deficient plasma.
Main Results:
- Hextend significantly decreased R compared to saline and Voluven in non-aprotinin samples.
- Aprotinin significantly increased R across all dilution conditions.
- No significant difference in R was observed with prekallikrein-deficient plasma.
Conclusions:
- Hextend accelerates kallikrein-dependent clot initiation more than saline or Voluven.
- Kallikrein activation is implicated in the effect of HES on clot initiation.
- Aprotinin mitigates the effect of HES on clot initiation.
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