[Postoperative hypertension in the surgery of the large arteries]

High incidence of postoperative arterial hypertension, confined to the first 24-48 hours and independent of the preoperative pressure situation, has been noted in patients following vascular surgery. The phenomenon is more frequent in patients whose angiosclerotic symptomatology goes back more than 2 years, and in those in whom preoperative investigation showed high daily variability in measured values, always however within non-pathological limits. Analysis of possible intraoperative pathogenetic factors in postoperative hypertension reveals a significant relationship between this phenomenon and inhalatory anesthesia, particularly with fluothane and curarization with D-tubocurarine. Co-responsibility of respiratory factors, particularly hypercapnia, has never been documented by haemogasanalysis. As for the pathogenetic mechanisms responsible for this type of hypertension, measurement of urinary catecholamines has revealed a close relationship between the two phenomena. The same investigation, extended to a wider group of patients, showed that by comparison with patients submitted to balanced anaesthesia, those who had received inhalatory anaesthesia with fluothane show, with much greater frequency, increased urinary elimination of catecholamines during the operation and for 24-48 hours afterwards. Catecholaminic hyperincretion, more frequent in fluothane anaesthesia, thus seems to be an important pathogenetic factor in these hypertensive manifestations in which the angiosclerotic medium presumably acts as an amplifier.