Ornipressin (Por 8): An Efficient Alternative to Counteract Hypotension During Combined General/Epidural Anesthesia

We sought to evaluate the efficacy and side effect profile of a small dose of ornipressin, a vasopressin agonist specific for the V1 receptor, administered to reverse the hypotension associated with combined general/epidural anesthesia. A total of 60 patients undergoing intestinal surgery were studied. After the induction of anesthesia, 7–8 mL of bupivacaine 0.5% with 2 μg/kg clonidine and 0.05 μg/kg sufentanil after an infusion of 5 mL of bupivacaine 0.06% with 0.5 μg · kg−1 · h−1 clonidine and 0.1 μg/h of sufentanil were administered by an epidural catheter placed at T7-8 vertebral interspace. When 20% reduction of baseline arterial blood pressure developed, patients were randomly assigned to receive, in a double-blinded design, dopamine started at 2 μg · kg−1 · min−1, norepinephrine started at 0.04 μg · kg−1 · min−1, or ornipressin started at 1 IU/h. Fifteen patients presenting without hypotension were used as control subjects. Beside routine monitoring, S-T segment analysis, arterial lactacidemia, and gastric tonometry were performed. Ornipressin restored arterial blood pressure after 8 ± 2 vs 7 ± 3 min in the norepinephrine group and 11 ± 3 min in the dopamine group (P < 0.05). This effect was achieved with 2 IU/h of ornipressin in most of the patients (11 of 15). Ornipressin did not induce any modification of the S-T segment; however, it significantly increased intracellular gastric Pco2 (P < 0.05), indicating splanchnic vasoconstriction. Implications In the population studied, small-dose ornipressin was effective to restore arterial blood pressure without causing major ischemic side effects.