Surgical treatment of hypertension

Abstract

There are three surgical measures which may be helpful in the management of hypertensive patients. Unilateral nephrectomy appears to have modified the course of the disorder in some patients. It appears to be difficult or impossible to predict the outcome. It seems permissible to remove a seriously damaged or non-functioning kidney when the other is little if at all affected. It seems unwise to remove the poorer of two involved kidneys. In general, the indications for nephrectomy should be the same in hypertensive as in non-hypertensive patients. The removal of adrenal tumors which are physiologically active is helpful. In those patients having paroxysmal hypertension the diagnosis can often be made with considerable certainty. On the other hand, paroxysmal forms of hypertension may not be due to tumors but appear to be the result of an intermittent increase in diencephalic activity. In these patients denervation of the splanchnic bed has been effective. Continued non-paroxysmal hypertension may be caused by an adrenal tumor. The diagnosis may be difficult to make and most of these tumors have been found unexpectedly during the course of operations upon the sympathetic nervous system. In general, active adrenal tumors are rare causes of hypertension. They almost always prove to be pheochromocytomas. Surgical intervention upon the sympathetic nervous system appears to offer many patients a reasonable chance for improvement at a minimal risk. It appears to slow the progress of the disorder. It probably is rarely if ever curative. A lessening of the severity of cardiovascular damage, as judged by favorable changes in the retinal, cardiac or renal areas, was noted in about 60 per cent of unselected patients followed from one to five or more years. Blood pressure levels were also modified slightly to markedly in about 60 per cent of these subjects. It is believed that at least part of the effect of the operation is due to a modification of reflex vasomotor fluctuations in blood pressure. This effect is independent of changes in blood pressure levels and occurs in virtually all thoroughly denervated patients. It is possible that elimination of reflex secretion of adrenalin and a stabilization of blood flow through the denervated area may be of some importance. Extensive sympathectomy has been utilized largely in patients who have reached the stage of continued hypertension with evidence of cardiovascular damage varying from slight to marked. Experience to date indicates that at least 30 per cent of these patients are clearly unsuited for this form of treatment and rules have been formulated in an attempt to exclude them as far as possible. If such patients are excluded, the early results in the remaining subjects are considerably better. A follow-up period of five years or more is needed to establish the circumstances under which splanchnicectomy is most likely to be worth while. It is gradually becoming apparent that patients with the best chance for good results are those in the younger age groups with narrower pulse pressures, (types 1 and 2) with variable blood pressures, the cardiovascular systems not too extensively damaged and with satisfactory responses to sedation. Two typical examples of patients ideally suited for surgical treatment are illustrated in Figures 2 and 3. A poor candidate for surgery is illustrated in Figure 4. Occasional patients develop evidence of cardiovascular damage in the stage of intermittent hypertension. In these it seems proper to consider surgical intervention. Thorough denervation of the splanchnic bed by a technic which permits exposure of the kidneys and adrenal glands appears to be the most desirable procedure for most patients. In some, total or subtotal thoracic sympathectomy may prove to be preferable.