[Intraoperative nitroglycerin: value of determining individual doses: (surgery of the abdominal aorta)].

Thirteen patients requiring infrarenal aortic clamping were studied during flunitrazepam, fentanyl, pancuronium and nitrous oxide anaesthesia. Each awake patient was submitted to a volume loading test to determine the haemodynamic status and his optimal left pre-load. Anesthetic induction was well tolerated. Nitroglycerin was administered by continuous infusion before aortic clamping and we determined the dose necessary to decrease the systemic vascular resistance by 20 per cent. This dose was very variable and needed to be increased in five of 13 patients at the time of clamping. With nitroglycerin, we noticed no significant alteration of MVO2 at clamping. Volume loading allowed good stability at declamping.