### Date : 2024-06-19 12:13 ### Topic : Thrombolysis #medicine #neurology #pulmonology #cardiology ---- ### Thrombolysis Overview **Thrombolysis** is a medical treatment aimed at dissolving blood clots that have acutely blocked blood vessels, thereby restoring blood flow and minimizing tissue damage. It is commonly used in conditions like acute ischemic stroke, myocardial infarction (heart attack), and pulmonary embolism. ### Mechanism of Action Thrombolytic agents, also known as fibrinolytic agents, work by breaking down fibrin, the main protein component of blood clots. These agents convert plasminogen to plasmin, an enzyme that digests fibrin and dissolves the clot. ### Common Thrombolytic Agents - **Alteplase (tPA):** Tissue plasminogen activator, commonly used for ischemic stroke and myocardial infarction. - **Reteplase:** A recombinant form of tPA, used for myocardial infarction. - **Tenecteplase:** A modified tPA with a longer half-life, used for myocardial infarction. - **Streptokinase:** Derived from streptococci bacteria, used for myocardial infarction and pulmonary embolism. ### Indications 1. **Acute Ischemic Stroke:** - Thrombolysis is indicated if administered within 3 to 4.5 hours of symptom onset. 2. **Acute Myocardial Infarction:** - Thrombolysis is indicated if primary percutaneous coronary intervention (PCI) is not available within 120 minutes of first medical contact. 3. **Pulmonary Embolism:** - Thrombolysis is indicated in cases of massive pulmonary embolism with hemodynamic instability. ### Contraindications Thrombolysis is contraindicated in certain conditions due to the risk of bleeding. Key contraindications include: - Active internal bleeding. - Recent major surgery or trauma (within 3 weeks). - History of hemorrhagic stroke or stroke of unknown origin. - Severe uncontrolled hypertension. - Known bleeding disorders. ### Clinical Setting: Thrombolysis in Acute Ischemic Stroke **Patient Profile:** - **Name:** Jee Hoon Ju - **Age:** 68 - **Occupation:** Retired Teacher **Medical History:** - **Symptoms:** Sudden onset of right-sided weakness and speech difficulty noted 1 hour ago. - **Medical Conditions:** Hypertension, well-controlled with medication. **Initial Assessment:** - **Neurological Examination:** Right-sided hemiparesis and aphasia. - **Glasgow Coma Scale (GCS):** 14 (indicating mild impairment). - **Time of Onset:** Symptoms began 1 hour ago. **Imaging:** - **CT Scan:** No evidence of hemorrhage, confirming ischemic stroke. **Diagnosis:** Acute ischemic stroke, likely due to an occlusion of a cerebral artery. **Management:** 1. **Eligibility for Thrombolysis:** - Based on the time window (within 4.5 hours of symptom onset) and absence of contraindications, Jee Hoon Ju is a candidate for thrombolytic therapy. 2. **Informed Consent:** - Discuss the risks and benefits of thrombolysis with the patient and family. 3. **Administration of Thrombolytic Agent:** - **Alteplase (tPA):** Administered intravenously at a dose of 0.9 mg/kg (maximum 90 mg). 10% of the total dose is given as an initial bolus over 1 minute, followed by the remaining 90% infused over 60 minutes. 4. **Monitoring:** - Continuous monitoring of neurological status, vital signs, and for any signs of bleeding. - Blood pressure should be closely monitored and controlled to reduce the risk of intracranial hemorrhage. **Post-Thrombolysis Care:** - **Neurological Assessment:** Frequent assessments to detect any changes in neurological status. - **Imaging:** Repeat CT or MRI scan if there is any deterioration in the patient’s condition. - **Supportive Care:** Maintain normoglycemia, normothermia, and appropriate hydration. Prevent complications like aspiration pneumonia. **Outcome:** - Successful thrombolysis can lead to significant improvement in neurological function, reducing long-term disability. ### Conclusion Thrombolysis is a critical intervention for patients with acute ischemic stroke, myocardial infarction, and pulmonary embolism. Careful patient selection, timely administration, and close monitoring are essential to maximize the benefits and minimize the risks associated with thrombolytic therapy. In a clinical setting, a multidisciplinary approach involving neurologists, cardiologists, radiologists, and critical care teams ensures optimal patient outcomes.