RESUMO
WHAT IS KNOWN AND OBJECTIVE: Somatostatin (SST) is used for the treatment of acute variceal bleeding based on its ability to decrease portal pressure and collateral blood flow. To date, no studies have focused on the immediate-early effects (between 1 and 30 min) of SST. The aim of this study was to compare the efficacy of different schedules of SST therapy with placebo on portal pressure in patients with portal hypertension treated with portal-azygous disconnection and to test whether an increase in bolus or infusion dose can improve the clinical efficacy of SST therapy. METHODS: Patients were treated with four different schedules: (a) standard dose (n = 11): one 250 µg bolus + a continuous infusion of 250 µg/h; (b) medium dose (n = 10): 500 µg bolus + a continuous infusion of 250 µg/h; (c) high dose (n = 10): 250 µg bolus + a continuous infusion of 500 µg/h; (d) control (n = 10): an injection of placebo (saline) followed by a placebo infusion. Following SST or placebo administration, portal pressure, central venous pressure (CVP), systemic blood pressure and heart rate (HR) were measured at 1, 3, 5, 7, 10 and 30 min. RESULTS AND DISCUSSION: The three schedules of SST induced a marked, rapid and highly significant decrease in portal pressure. The decline in portal pressure was moderate at 1 min (P < 0·040), achieved a peak effect at 5 min (P < 0·009) and remained decreased at 30 min. The effect of SST on portal pressure was significantly greater than placebo from 1 min after administration. There were no significant differences in portal pressure decrease between the three schedules of SST. The three schedules of SST and the placebo schedule did not induce significant changes in HR, systemic blood pressure and CVP. WHAT IS NEW AND CONCLUSION: This study shows that SST is effective in decreasing portal pressure within 30 min of administration in patients with liver cirrhosis. The clinical schedule used in this study was reasonable and safe.