Massive haemorrhage caused by left renal vein ligation.

It is common practice to ligate the left renal vein during aortic surgery. Although this does not usually lead to complications we report 2 patients in whom left renal vein ligation caused massive venous congestion of the kidney and major retroperitoneal haemorrhage. Nephrectomy was necessary to control the haemorrhage. In 1 patient immediate autotransplantation preserved renal function.