The mesenteric artery is the primary vessel responsible for splanchnic circulation as it supplies blood to the majority of the gastrointestinal tract, including the small intestine, large intestine, stomach, and pancreas. This vascular territory is critical for nutrient absorption and gut function. Surgical procedures involving the abdomen must carefully preserve mesenteric blood flow to prevent ischemia and bowel necrosis. Understanding the anatomy of the superior and inferior mesenteric arteries is essential in abdominal surgeries, especially in vascular reconstructions and trauma management. Disruption can lead to life-threatening complications such as mesenteric ischemia.

Reference: Gray's Anatomy, Susan Standring, 42nd Edition.