PURPOSE: "Lyse and wait" dialysis graft declotting is simple and effective, but the minimum necessary dose of urokinase is unknown. The efficacy of the technique with very low dose urokinase is evaluated.

MATERIALS AND METHODS: Twenty-one grafts in 17 patients were declotted with use of the lyse and wait technique, but with 5,000-15,000 U of urokinase initially. Graft angiography was performed when an interventional suite was available. Declotting was completed in the manner chosen by the individual operator. Angiograms, interventional radiology records, and dialysis records were reviewed.

RESULTS: Technical and clinical success were achieved in 95% of cases. Mean initial urokinase dose was 6,667 U. Initial angiography was performed at a mean 86 minutes. Two cases required second 5,000-U boluses to achieve complete graft thrombolysis. In all other cases, complete or near complete graft thrombolysis was observed with the initial very low dose. No bleeding, arterial embolic, or pulmonary embolic complications were observed.

CONCLUSIONS: Doses of urokinase as low as 5,000 U are effective for lyse and wait declotting. A substantial reduction in drug costs can be expected with the "less and wait" modification. Bleeding risk may also be reduced.