Decreased mesenteric blood flow in experimental multiple organ failure

Area of Science:

• Physiology
• Gastroenterology
• Critical Care Medicine

Background:

• Disorders of mucosal blood flow are implicated in gut barrier dysfunction during multiple organ failure (MOF).
• Mesenteric microcirculation plays a critical role in maintaining gut integrity and function.

Purpose of the Study:

• To evaluate alterations in mesenteric microcirculation within a rat model of MOF.
• To investigate the relationship between mesenteric blood flow changes and gut barrier function in MOF.

Main Methods:

• Male Wistar rats were administered zymosan A intraperitoneally to induce MOF, with fluid resuscitation provided.
• Mesenteric arteriolar diameter and laser Doppler velocity were measured on Days 1, 3, and 5 post-injection.
• Data were compared against a control group receiving no zymosan.

Main Results:

• Animals in the MOF model exhibited significantly lower mean arterial pressure on Day 1 compared to controls.
• Significant arteriolar vasoconstriction (reduced diameter) was observed on Days 1 and 3 in the MOF group.
• Red blood cell velocity, measured by laser Doppler, decreased in parallel with vasoconstriction, indicating reduced mesenteric perfusion.

Conclusions:

• Mesenteric arteriolar vasoconstriction and decreased red blood cell velocity occur in this zymosan-induced rat model of MOF.
• These microcirculatory changes suggest compromised mesenteric perfusion, potentially contributing to gut barrier dysfunction.
• Survival to Day 5 in this model was associated with a reversal of these observed microcirculatory alterations.