Canine Gastric Acid Secretion and Blood Flow Measurement in Hemorrhagic Shock

In 5 anesthetized and 5 conscious dogs, gastric blood flow was measured with 15-μ labeled microspheres. Acid secretion and regional flow under control conditions (mean blood pressure (BP) = 100 mm Hg), after 1 hr of hemorrhagic shock (mean BP = 40 mm Hg), and 60 min after re transfusion of shed blood (mean BP = 100 mm Hg) were measured. Results are expressed as mean milliequivalents per hour for acid secretion and milliliters per minute x 100 g of tissue for blood flow. These results indicate that (1) acid secretion and regional blood flow are significantly higher in conscious dogs; (2) hemorrhagic shock caused a significant reduction of acid secretion and blood flow within the gastric tissue; (3) blood flow to fundic mucosa decreases more than antral mucosa (P < 0.05) in anesthetized dogs; and (4) although re transfusion increased regional blood flow, it was not restored to preshock level. Because the perfusion of fundic mucosa is more sensitive to hemorrhagic shock, this may partially explain the propensity of stress ulcers to be located in the fundus of the stomach.