A protocol for the safe treatment of acute lower limb ischaemia with intra-arterial streptokinase and surgery.

Over a 5-year period 70 patients, presenting with subacute ischaemia of the lower limb (more than 12 h), were treated with low-dose intra-arterial streptokinase. There were 72 infusions and effective lysis was achieved in 52 (72 per cent), with an average infusion time of 25 h. A total of 23 (32 per cent) also underwent percutaneous transluminal angioplasty when lysis showed an underlying stenosis, and a further 19 (26 per cent) required surgery to remove persistent stenosis, organized thrombus or atheromatous debris. Significant bleeding occurred in 4 patients (6 per cent) and 13 (18 per cent) underwent amputation. There were five deaths (7 per cent), one of which was directly related to the infusion, while three were due to myocardial infarction. All of the major complications occurred in the early part of the study and both the selection of patients and the technique of infusion were modified to improve safety. Complementary treatment by percutaneous transluminal angioplasty and surgery was used more frequently in the later part of the study. The technique is not recommended for the white leg of acute ischaemia (less than 12 h), or for lysis of clot in a retroperitoneal Dacron graft, but may be uniquely valuable to demonstrate the cause of subacute ischaemia.