Fibrinolytic Drugs Flashcards
What are the major fibrinolytic drugs? (5)
- Streptokinase
- Alteplase
- Reteplase
- Tenecteplase
- Urokinase
What are the indications of thrombolytics? (4)
- Any patient with acute MI for whom the benefit is likely to outweigh the risk of treatment
- Thromboembolic disorders such as DVT and PE
- Restoration of patency of occluded IV cataheters and cannulas blocked by fibrin clots (urokinase only)
- Ischemic stroke (alteplase only)
Can fibrinolytics be used in stroke management?
Only ALTEPLASE in management of acute ISCHEMIC stroke under specialist neurology physician ONLY
Which thrombolytic drugs have been shown to reduce mortality when given in the treatment of MI? (2)
- Streptokinase
2. Alteplase
For which 2 ECG changes are thrombolytics shown to have the greatest benefit when treating acute MI?
- ST segment elevation (especially anterior infarction)
2. Bundle branch block
What is the ideal window for administering thrombolytics?
Ideally, all should be given within 1 hour; use after 12 hours requires specialist advice
- alteplase should be given within 6-12 hours of symptom onset
- reteplase and streptokinase within 12 hours
- tenecteplase ASAP but usually within 6 hours
What is the mechanism of action of fibrinolytics?
Activation of plasminogen to form plasmin, which degrades fibrin and so breaks up thrombi
What are the side effects of fibrinolytic drugs that require treatment to be stopped? (8)
- Serious bleeding (including CNS hemorrhage)
- Allergic reaction
- Cardiogenic shock
- Cardiac arrest
- Hypotension
- Angina pectoris
- Pericarditis
- Pulmonary edema
*serious bleeding may require treatment with coagulation factors and antifibrinolytic drugs eg tranexamic acid
What are potential consequences of reperfusion therapy in infarcted brain or heart tissue?
Cerebral edema
Arrhythmia
Can fibrinolytics be used in pregnancy?
Not advised
Thrombolytic drugs can possibly lead to premature separation of the placenta in the first 18 weeks of pregnancy. There is also a risk of maternal haemorrhage throughout pregnancy and post-partum, and also a theoretical risk of fetal haemorrhage throughout pregnancy.
What are the monitoring requirements for fibrinolytics when used in the treatment of ischemic stroke?
(Alteplase only)
- monitor for intracranial hemorrhage
- monitor blood pressure (antihypertensives recommended if systolic BP>180 or diastolic BP>105)
What are the main drug interactions to avoid when using fibrinolytics? (8)
Avoid co-prescription with other drugs that may cause bleeding eg
- aspirin, clopidogrel, and dipyridamole
- NSAIDs
- biologics
- prostacyclins
- SSRIs
- DOACs
- heparins
- mefenamic acid
*increased risk of anaphylactic reaction when co-prescribed with ACEi
What are the main contraindications to fibrinolytic therapy? (13)
- Factors that predispose to bleeding (eg recent hemorrhage, recent trauma or surgery, bleeding disorders, severe HTN, peptic ulcer)
- Intracranial hemorrhage (must be excluded by CT before initiating treatment)
- Previous streptokinase treatment (although other fibrinolytics can be used) due to potential development of anti-streptokinase antibodies which block its effect
- Acute pancreatitis
- Aneurysm
- Aortic dissection
- AV malformation
- Bacterial endocarditis
- Coma
- Heavy vaginal bleeding
- Neoplasm with risk of hemorrhage
- Esophageal varices
- Pericarditis
What are the specific contraindications to using alteplase in the setting of acute ischemic stroke? (6)
- Convulsion accompanying stroke
- History of stroke in patient with diabetes
- Hyperglycemia
- Hypoglycemia
- Severe stroke
- Stroke in the last 3 months
(Think factors that may increase the risk of cerebral hemorrhage)
Are fibrinolytics safe to prescribe in hepatic impairment?
Avoid in severe impairment
