Intraoperative lytic therapy: agents and methods of administration

Intraoperative intraarterial thrombolysis is a valuable adjunct for the removal of residual arterial thrombi after mechanical thromboembolectomy. Early reports by some investigators indicated high rates of bleeding complications, most likely caused by inappropriately high doses of plasminogen activators infused over long periods of time, which led to systemic lytic effects. Animal models and controlled human experiments subsequently have shown the potential efficacy and safety of intraarterial thrombolysis. Since urokinase (UK) has been withdrawn from the market, recombinant tissue-type plasminogen activator (rt-PA) has become the plasminogen activator of choice. Reteplase and other plasminogen activators may be beneficial (and safe); however, data on intraoperative use currently are not available. The most common methods of delivery into the distal arterial tree are bolus infusion with inflow occlusion, drip infusion after restoration of arterial inflow, and the isolated limb perfusion technique. The number of distal vessels involved, the amount of residual thrombus, and severity of ischemia guide the dose of plasminogen activator, volume of perfusate, and the technique and duration of infusion.