The Effect of Oral Nitroglycerin on Portal Blood Velocity as Measured by Ultrasonic Doppler: A Double Blind, Placebo Controlled Study

We studied the effect of oral nitroglycerin on portal blood velocity (PBV) in 20 cirrhotic patients by a double blind, olacebo controlled method using noninvasive Doppler onography. After we obtained baseline Doppler in the asting state, 0.6 mg nitroglycerin or placebo was given orally and the mean of 3 s averaged mean PBVs was epeated at 5 min intervals for 60 min. Ten patients each eceived nitroglycerin or placebo. Portal vein flows were ntegrade in all. Of the 10 patients receiving nitroglycrin, seven (P = 0.002) showed a greater than 10% fall in he mean PBVs for at least 15 min. Of these seven responders, “five patients had a 10% decrease in mean systemic blood pressure for at least 15 min. None of the nonresponders” had systemic hypotension. Our study suggests that the PBV-reducing effect of nitroglycerin in cirrhotics may be explained in part by systemic hypotension.