Equine Gastrointestinal Lesions – NAVLE Study Guide

Overview and Clinical Importance

Colic is the leading cause of death in horses and represents the most common equine emergency presented to veterinarians. Understanding the distinction between strangulating and non-strangulating lesions is critical for the NAVLE, as it directly impacts treatment decisions, surgical urgency, and prognosis.

Strangulating lesions involve vascular compromise leading to ischemia and rapid tissue necrosis, requiring emergency surgical intervention. Non-strangulating lesions obstruct the intestinal lumen without immediate vascular compromise and may respond to medical management. The ability to differentiate these conditions clinically determines whether a horse survives.

Key Definitions and Classifications

Strangulating Obstruction

A strangulating obstruction involves both luminal obstruction AND vascular compromise. The blood supply to the intestinal wall is interrupted, leading to ischemia, mucosal barrier breakdown, bacterial translocation, endotoxemia, and rapid tissue death. These are surgical emergencies with a narrow window for intervention.