The effects of pharmacological manipulation of the lower esophageal sphincter pressure on the esophageal circulation in patients with cirrhosis and portal hypertension were investigated in 33 patients by measuring the azygos venous blood flow, which is an index of blood flow through esophageal varices and periesophageal collaterals draining into the azygos venous system. Measurements were performed in baseline conditions and after the blind administration of metoclopramide (20 mg i.v.) (12 patients), domperidone (10 mg i.v.) (12 patients) and placebo (9 patients).
Both metoclopramide and domperidone caused a significant reduction of azygos blood flow, that decreased by 11.5% (p < 0.01) and 15.6% (p < 0.02) respectively, while no change was observed in patients receiving placebo (+1.4%, not statistically significant). Reduction of azygos blood flow represents a selective effect of metoclopramide and domperidone on the esophageal circulation, since portal pressure, hepatic blood flow, cardiac output, heart rate and arterial blood pressure were unchanged by the administration of metoclopramide, domperidone or placebo.
These results indicate that the administration of drugs that increase the lower esophageal sphincter pressure may reduce the inflow of blood into the esophageal varices in cirrhotic patients with portal hypertension.