EFFECTS OF KETOROLAC TROMETHAMINE (TORADOL(R)) ON A FUNCTIONAL-MODEL OF MICROVASCULAR THROMBOSIS

Ketorolac tromethamine (Toradol(R)), a potent nonsteroidal anti-inflam matory drug used for postoperative pain, also strongly inhibits platel et agregation. The anti-thrombotic effects of intramuscular ketorolac were assessed with a described rat model of microarterial thrombosis. After a single dose of ketoroiac mean bleeding times were significantl y prolonged (p < 0.01) and platelet aggregation was markedly reduced. Patency rates at 20 min were significantly higher in ketorolac groups compared to controls (p < 0.005). However, all vessels were thrombosed at 24 h. Scanning electron microscopy demonstrated decreased platelet aggregation and decreased thrombus formation in ketorolac treated ani mals at 20 min. The prolonged bleeding time and reduction in platelet aggregation add support to concerns of bleeding complications reported in patients treated with ketorolac perioperatively. Thus, ketorolac s hould probably not be used for pain relief in patients in whom postope rative haematoma formation is a particular concern. In addition, in th is model, ketorolac as a single agent was ineffective for long-term pr evention of microarterial thrombosis.