To determine the optimal perfusion volume for the celiac artery (CA) and superior mesenteric artery (SMA) in a porcine model. Fifteen Yorkshire pigs (46.7 ± 5.2 kg) underwent selective CA and SMA perfusion using a roller pump at either 400 mL/min (G400, n = 5) or 800 mL/min (G800, n = 6). Hemodynamic parameters, blood gas analyses, and biochemical markers were evaluated over time (T1 to T5). The intestinal tissue was assessed for edema and histological damage. Portal vein SvO2 was lower in G400 (65.0 ± 30.2% at T2) compared to G800 (87.0 ± 5.2%), indicating reduced perfusion. Lactate levels were significantly higher in G400 (7.8 ± 2.3 mmol/L at T2) than in G800 (4.1 ± 2.1 mmol/L), suggesting increased anaerobic metabolism. Aspartate aminotransferase levels were elevated in G400, reflecting intestinal ischemia, whereas alanine aminotransferase levels remained stable. Histological analysis revealed mucosal desquamation in G400 but not in G800. No significant differences in intestinal edema were observed between groups. A selective perfusion volume of 800 mL/min for the CA and SMA maintains portal vein SvO2 and prevents mucosal injury, suggesting it approximates physiological blood flow. These findings indicate that increasing selective visceral perfusion during thoracoabdominal aortic surgery may reduce postoperative intestinal complications and improve patient outcomes.