Blood in the gastric lumen increases splanchnic blood flow and portal pressure in portal-hypertensive rats.
OBJECTIVE
In portal-hypertensive humans, portal blood flow and pressure increase after a meal. These hemodynamic changes may increase variceal rupture risk. The aim of this study was to determine whether blood in the stomach lumen increases splanchnic flow and portal pressure (PP) in portal-hypertensive rats.


METHODS
superior mesenteric artery flow and PP were measured in conscious, unrestrained, fasted partial portal vein-ligated rats with chronically implanted Doppler flow probes or portal vein catheters before and after gavage with heparinized, warmed blood from donor rats, air, standard meal, or empty tube.


RESULTS
Percentage of changes in flow and pressure from baseline were significantly greater after gavage with blood (an increase of 22.6% +/- 3.5% and an increase of 16.4% +/- 3.1%, respectively) than empty tube (an increase of 3.4% +/- 0.6% and a decrease of 5.4% +/- 3.5%, respectively) (P < 0.005). Percentage of changes in flow and pressure were slightly but insignificantly greater after gavage with air vs. empty tube (P < 0.005).


CONCLUSIONS
In portal-hypertensive rats, blood in the stomach lumen significantly increases splanchnic blood flow and PP. Splanchnic hyperemia from absorption of blood's calories probably contributes to these hemodynamic changes. In patients with variceal hemorrhage, blood in the stomach may increase the risk of persistent variceal bleeding or rebleeding.
Chen
L
L
Department of Digestive Diseases, VA Medical Center/Yale University School of Medicine, New Haven, Connecticut, USA.
Groszmann
R J
RJ
D000818:Animals; D002406:Catheterization, Peripheral; D004932:Esophageal and Gastric Varices / Q000150:complications; D006471:Gastrointestinal Hemorrhage / Q000209:etiology; D006975:Hypertension, Portal / Q000503:physiopathology*; D008297:Male; D017082:Portal Pressure; D051381:Rats; D017207:Rats, Sprague-Dawley; D013152:Splanchnic Circulation; D013270:Stomach / Q000098:blood supply*