Hemodynamic and hematologic changes in a standardized trauma-sepsis model in rats

Area of Science:

• Physiology
• Sepsis Research
• Animal Models

Background:

• Trauma and sepsis are critical conditions requiring robust experimental models.
• Understanding the physiological impact of escalating bacterial loads is crucial for developing effective treatments.

Purpose of the Study:

• To establish and characterize an experimental trauma-sepsis model in rats.
• To investigate the dose-dependent effects of Escherichia coli on survival and physiological parameters.

Main Methods:

• Sepsis was induced in rats via intravenous infusion of live Escherichia coli (10^8-10^10 CFU).
• Survival rates were monitored up to 7 days.
• Cardiac output (dye-dilution) and hepatic blood flow (133Xe washout) were measured at 24 hours.
• Hematologic parameters, pulse rate, and blood pressure were also assessed.

Main Results:

• Survival rates decreased in a dose-dependent manner with increasing E. coli doses.
• Cardiac output and hepatic blood flow showed a graded reduction corresponding to bacterial load.
• Hematologic changes, including decreased platelet and white blood cell counts, were more pronounced with higher bacterial doses.

Conclusions:

• A standardized rat model of trauma-sepsis was successfully established.
• The model demonstrates a clear, graded physiological response to increasing bacterial inocula.
• This model is valuable for studying metabolic responses to trauma and sepsis.