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Updated: Jun 5, 2026

Fixed Volume or Fixed Pressure: A Murine Model of Hemorrhagic Shock
Published on: June 6, 2011
Improved resuscitation from hemorrhagic shock with Ringer's lactate with increased viscosity in the hamster window
Nivaldo R Villela1, Amy G Tsai, Pedro Cabrales
1Department of Bioengineering, University of California, San Diego, La Jolla, California 92093-0412, USA.
Background:
Infusion of large volume of fluid is practiced in the treatment of hemorrhagic shock although resuscitation with small fluid volumes reduces the risks associated with fluid overload. We explored the hypothesis that reduced Ringer's lactate (RL) volume restoration in hemorrhage is significantly improved by increasing its viscosity, leading to improved microvascular conditions.
Methods:
Awake hamsters were subjected to a hemorrhage of 50% of blood volume followed by a shock period of 1 hour. They were resuscitated with conventional RL (n = 6) or with RL whose viscosity was increased by the addition of 0.3% alginate (RL-HV) (n = 6). In both cases, the volume infused was 200% of shed blood.
Results:
After resuscitation, blood and plasma viscosities were 1.9 cp ± 0.18 cp and 1.0 cp ± 0.03 cp in RL and 2.5 cp ± 0.34 cp and 1.6 cp ± 0.05 cp in RL-HV. Mean arterial pressure was lower than baseline in RL. Arteriolar diameter and arteriolar and venular flow were significantly higher in RL-HV. Functional capillary density was significantly higher in RL-HV than RL. After 90 minutes of resuscitation, functional capillary density was lower than baseline in RL, whereas it was maintained in RL-HV. Arteriolar PO₂ was higher in RL-HV than RL. Microcirculation O₂ delivery and tissue PO₂ were significantly higher in RL-HV.
Conclusions:
Increasing blood and plasma viscosities in resuscitation from hemorrhagic shock with increased viscosity RL improves microvascular hemodynamics and oxygenation parameters.

