Alteplase

Definition

Alteplase is a recombinant tissue plasminogen activator (tPA) used primarily as a thrombolytic agent to dissolve blood clots in cases of acute ischemic stroke, myocardial infarction, and pulmonary embolism. It works by converting plasminogen to plasmin, which breaks down fibrin in the blood clots, thereby restoring blood flow to affected areas. Alteplase is critical in emergency medicine for its ability to significantly reduce morbidity and mortality associated with thromboembolic events.

5 Must Know Facts For Your Next Test

1. Alteplase must be administered within a specific time window (typically within 3 to 4.5 hours) after the onset of symptoms for it to be effective in treating acute ischemic stroke.
2. Patients receiving alteplase should be closely monitored for potential bleeding complications, as it can increase the risk of hemorrhage due to its mechanism of action.
3. Alteplase can also be used in the treatment of acute myocardial infarction when percutaneous coronary intervention is not immediately available.
4. The use of alteplase is contraindicated in patients with certain conditions such as recent surgery, active bleeding, or a history of intracranial hemorrhage.
5. Alteplase is typically administered intravenously and requires careful dosage adjustments based on the patient's weight.

Review Questions

• How does alteplase function as a thrombolytic agent and what are its primary indications?
  • Alteplase functions by converting plasminogen into plasmin, which then dissolves fibrin in blood clots. This process restores blood flow to areas that have become ischemic due to the blockage caused by clots. The primary indications for alteplase include acute ischemic stroke, myocardial infarction, and pulmonary embolism, making it essential in emergency medical scenarios.
• What are the key contraindications for using alteplase, and how do these impact patient selection?
  • Key contraindications for using alteplase include recent surgery, active bleeding, uncontrolled hypertension, and a history of intracranial hemorrhage. These contraindications are crucial because they help clinicians assess the risk versus benefit of administering alteplase. A thorough patient history and risk assessment ensure that only suitable candidates receive this potent thrombolytic treatment.
• Evaluate the implications of alteplase administration timing on patient outcomes in cases of acute ischemic stroke.
  • The timing of alteplase administration is critical in determining patient outcomes following an acute ischemic stroke. Studies show that administering alteplase within the recommended window of 3 to 4.5 hours significantly improves the chances of recovery and reduces long-term disability. Delays beyond this time frame can lead to worse outcomes due to irreversible brain damage from prolonged ischemia, highlighting the importance of rapid assessment and treatment initiation.

Related terms

Thrombolytics: A class of medications designed to dissolve blood clots by activating the fibrinolytic system, often used in emergencies like heart attacks or strokes.

Plasminogen: An inactive precursor of plasmin that, when activated, helps dissolve fibrin in blood clots.

Ischemia: A condition characterized by insufficient blood flow to a tissue, often leading to damage or dysfunction in that area.