BETA-ADRENERGIC STIMULATION AND BLOCKADE IN CIRRHOSIS - EFFECTS ON AZYGOS VEIN BLOOD-FLOW AND PORTAL HEMODYNAMICS

It is unknown whether beta adrenergic stress has adverse hepatic hemod ynamic effects. Therefore, the authors studied the hemodynamic effects of beta adrenergic stimulation and subsequent blockade in 10 patients with cirrhosis (6 Childs A, 3 Childs B, and 1 Childs C) with known or suspected portal hypertension. Free and wedged hepatic vein pressures , hepatic venous pressure gradient, heart rate, mean arterial pressure , cardiac output, and azygos vein blood flow were measured at rest and after isoproterenol infusion (mean dose = 7.3 mu g/min: target heart rate = 150% to 200% of resting heart rate). Esmolol, an ultra-short-ac ting beta blocker, was then infused (dose titrated to return heart rat e to baseline), and all measurements were repeated. Based on the resul ts, the authors conclude that beta adrenergic stress provoked by isopr oterenol infusion significantly increases azygos vein blood flow and h epatic venous pressure gradient. Beta blockade with esmolol reduces az ygos vein blood flow and hepatic venous pressure gradient significantl y below baseline.