Simulated small intestinal volvulus in the anesthetized horse.

Area of Science:

• Veterinary Medicine
• Equine Surgery
• Surgical Pathophysiology

Background:

• Small intestinal volvulus is a critical surgical emergency in horses.
• Anesthesia can mask or delay the presentation of shock and surgical complications.
• Understanding physiological changes during induced volvulus is crucial for diagnosis and treatment.

Purpose of the Study:

• To investigate the clinical and physiological effects of experimentally induced small intestinal volvulus in anesthetized horses.
• To compare the presentation of shock and volvulus signs in anesthetized versus conscious horses.
• To establish dose-response relationships between intestinal damage and measured parameters.

Main Methods:

• Experimental induction of small intestinal volvulus in anesthetized horses via mesenteric vein ligation.
• Monitoring of hemodynamic, hematologic, clinical chemical, bacteriologic, and peritoneal fluid parameters.
• Assessment of physical signs related to shock and gastrointestinal dysfunction.

Main Results:

• Anesthesia significantly delayed and modified clinical signs of shock and small intestinal volvulus.
• A dose-response relationship was observed between the extent of intestinal damage and clinical symptoms.
• Metabolic acidosis, elevated lactate, and altered electrolyte levels indicated insufficient tissue perfusion due to shock.

Conclusions:

• Anesthesia profoundly impacts the clinical manifestation of small intestinal volvulus and associated shock in horses.
• Despite modified signs, a correlation exists between intestinal damage severity and physiological derangements.
• These findings highlight the importance of careful monitoring and interpretation of parameters in anesthetized horses with suspected gastrointestinal emergencies.