Fibrinolytic therapy administration

GP Ilb/IIIa inhibitors may increase the risk of bleeding, especially if given in the setting of recent (<4 hours) administration of fibrinolytic therapy. An immune-mediated thrombocytopenia occurs in about 5% of patients. 

Ultrasound-assisted soft digestion has been used for other practical purposes from which analytical chemists can derive new applications. One case in point is in medicine, where ultrasound has been used as an adjunctive therapeutic treatment for clot dissolution of pharmacological thrombolysis. The combination of externally applied low-frequency high-intensity US with fibrinolytic therapy resulted in more rapid and complete reperfusion than the application of US or administration of fibrinolytic agents alone [42]. 

Data regarding the acute benefit of /3-blockers in MI in the reperfusion era is derived mainly from the Thrombolysis in Myocardial Infarction (TIMI) II trial. In this trial, patients with ST-segment-elevation ACS were randomized to either IV metoprolol to be given as soon as possible following fibrinolytic administration followed by oral metoprolol or oral metoprolol deferred until day 6. Early administration of metoprolol was associated with a significant decrease in recurrent ischemia and early reinfarction. Patients receiving fibrinolytic therapy within 2 hours of symptom onset demonstrated the greatest benefit from early metoprolol administration. Based on the results of these trials, early administration of /8-blockers (to patients without contraindications) within the first 24 hours of hospital admission is a standard of quality patient care (see Table 16-3). 

Initial fibrinolytic therapy (in patients who have no absolute contraindication to thrombolysis) should be combined with administration of conjunctive pharmacological agents to enhance lysis and minimize the risk of Weeding. 

Meta-analysis of six trials of prehospital fibrinolysis including 6434 patients suggests that its use is associated with a substantial reduction in time to treat (58 min) and a 17% relative risk reduction of mortality (45). However, these studies were largely performed in European centers with mobile care units staffed by physicians and nurses experienced in the administration of fibrinolytic therapy, a scenario uncommon in American care systems. Therefore, the applicability of such findings is limited in the United States. 

Early reperfusion therapy with either primary percutaneous coronary intervention or administration of a fibrinolytic agent within 3 hours of symptom onset is the recommended therapy for patients presenting with ST-segment elevation acute coronary syndrome. 

Efforts to decrease the time until therapy was initiated to maximize both the rate of success of lytic therapy [fresher clots are more susceptible to lysis, especially with nonfibrin-specific agents (5)] and the impact of reperfusion on myocardial salvage led to a shift to intravenous administration of these drugs, which could be performed in the coronary care unit (CCU) or the emergency department (ED), saving 1-2 hours between diagnosis and the initiation of therapy. Trials performed with angiographic assessment after the initiation of thrombolytic therapy are patency studies infarct-related vessels found to be patent will include those that contained clot that was successfully dissolved by the therapy delivered, those that contained clot that resolved because of the body s own fibrinolytic mechanisms before therapy was instituted, and those that never had intracoronary thrombus as an occlusive event. 

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