From the Guidelines
The recommended dose of alteplase for acute ischemic stroke is 0.9 mg/kg, with a maximum total dose of 90 mg, administered intravenously with 10% of the total dose given as an initial bolus over 1 minute, followed by the remaining 90% infused over 60 minutes. This dosing regimen is supported by the most recent guidelines from the American Heart Association/American Stroke Association, as outlined in the 2018 guidelines for the early management of patients with acute ischemic stroke 1. The medication should be administered as soon as possible after hospital arrival, with a target door-to-needle time of less than 60 minutes in 90% of treated patients, and a median door-to-needle time of 30 minutes 1. Before administration, patients must be carefully screened to ensure they are within the appropriate time window (generally within 3-4.5 hours of symptom onset) and do not have contraindications such as recent surgery, active bleeding, or uncontrolled hypertension. Blood pressure should be maintained below 180/105 mmHg before and during infusion. Weight-based dosing is critical for efficacy and safety, as alteplase works by converting plasminogen to plasmin, which breaks down fibrin clots to restore blood flow to the ischemic brain tissue. The narrow therapeutic window exists because the benefit of reperfusion diminishes while the risk of hemorrhagic transformation increases with time from symptom onset. Continuous cardiac and neurological monitoring is essential during administration to detect potential complications. Key considerations for administration include:
- Eligibility criteria, such as time from symptom onset, age, and stroke severity
- Contraindications, such as recent surgery, active bleeding, or uncontrolled hypertension
- Monitoring of blood pressure and neurological status during and after infusion
- Delaying placement of invasive devices, such as nasogastric tubes or indwelling bladder catheters, unless necessary
- Obtaining a follow-up CT or MRI scan at 24 hours after alteplase administration before starting anticoagulants or antiplatelet agents.
From the Research
Dose of Alteplase in Acute Ischemic Stroke
The dose of alteplase in acute ischemic stroke is a crucial aspect of treatment. According to the studies, the standard dose of alteplase is 0.9 mg/kg, with a maximum dose limit of 90 mg 2.
Standard Dose vs. Low-Dose Alteplase
Some studies have investigated the use of low-dose alteplase (0.6 mg/kg) in acute ischemic stroke patients. The results suggest that low-dose alteplase may be preferable in patients with a combination of favorable characteristics, including younger age, lower systolic blood pressure, mild neurological impairment, and no atrial fibrillation, diabetes mellitus, or premorbid symptoms 3.
Key Points
- The standard dose of alteplase is 0.9 mg/kg, with a maximum dose limit of 90 mg 2.
- Low-dose alteplase (0.6 mg/kg) may be beneficial in patients with favorable characteristics, such as younger age and mild neurological impairment 3.
- The optimal dose of alteplase in patients with stress hyperglycemia is uncertain, but low-dose alteplase may demonstrate more significant neuroprotective effects 4.
- The use of low-dose alteplase requires further validation through large-scale, randomized controlled trials 4.
Patient Characteristics and Alteplase Dose
Patient characteristics, such as weight, age, and comorbidities, can influence the choice of alteplase dose. For example, patients weighing over 100 kg may receive a lower per-kilogram dose of alteplase, but this does not appear to affect the outcome 2.
Outcome Measures
Outcome measures, such as functional independence and mortality, can be used to evaluate the effectiveness of alteplase treatment. Studies have shown that alteplase treatment can improve functional independence and reduce mortality in acute ischemic stroke patients 5, 2.