Evaluation of the Early Use of Norepinephrine in Major Abdominal Surgery on Postoperative Organ Dysfunction

The control group will be taken care of according to the protocols in force. The first anesthetic post-induction hypotension will be managed by intravenous injection of ephedrine (dilution: 3 mg / ml) at a dose of 6 mg (i.e. 2 ml). Any subsequent hypotension will be treated with ephedrine until injection of a total dose of 30 mg. Thereafter, if a new arterial hypotension occurs, we will pass to the administration of noradrenaline in intravenous injection using an electric syringe pump, at the dilution of 0.016 mg / ml, posology adapted to the objectives. blood pressure.

Immediately use of norepinephrine by intravenous injection using an electric syringe pump, at a dilution of 0.016 mg / ml, at the time of anesthetic induction and without waiting the 1st possible arterial hypotension. Noradrenaline will be started at a dose of 0.48 mg / h and then adapted according to the blood pressure objectives.