[Clinical and experimental study on vascular reconstruction for one-kidney renovascular hypertension]

Several special problems were noted regarding the vascular reconstruction for renovascular hypertension of the patient with a solitary kidney. It is difficult to use the value of plasma renin activity for decisive diagnosis or determination of surgical indications because most of the one-kidney patients with renovascular hypertension showed a normal plasma renin activity preoperatively and it is theoretically impossible to obtain a ratio of the affected to the opposite renal vein renin level. Most patients presented moderate to severe degree of renal dysfunction so that vascular reconstruction should be the treatment of choice because the conservative therapy with anti-hypertensive drugs such as captopril may further worsen the renal function by decreasing the renal perfusion pressure. Patients showed extensive polyuria immediately after surgery which was attributed to sudden increases in glomerular filtration rate and urinary sodium excretion. There was no correlation between the preoperative serum osmolarity and the postoperative polyuria. Correlation was not obtained between the intraoperative clamping time of the renal artery and the aggravation of the previously existing renal dysfunction. A comparative pathohistological study of primarily vs secondarily nephrectomized kidneys revealed no evidence of parenchymal damage of the kidney after arterial reconstruction. Both acute and chronic animal experiments in which autologous whole blood was forcibly injected into the canine renal artery via extracorporeal shunt under the high pressure of 200 or 300 mmHg showed no light microscopic evidence of acute histological damage of the kidney. It is concluded that the intensive care with an aid of a Swan Ganz catheter during the postoperative polyuric period and the swift starting of hemodialysis when necessary can solve the postoperative problems of one-kidney renovascular hypertension although the sudden rise in renal perfusion pressure after reconstruction may cause an acute hypertensive damage in the level of electron microscopic findings.