tPA Calculator – Stroke Dosing
Calculate accurate alteplase (tPA) dosing for acute ischemic stroke treatment
Calculate tPA Dose for Stroke
This calculator is for healthcare professionals only. tPA administration requires immediate medical supervision. Always verify calculations and follow institutional protocols. Incorrect dosing can be life-threatening.
Actual body weight for tPA dosing calculation
Example Calculation
Stroke Patient Example
Patient: 70-year-old presenting with acute stroke symptoms
Weight: 70 kg
Onset time: 2 hours ago (within window)
CT scan: No hemorrhage, eligible for tPA
Calculation
Total dose = 0.9 mg/kg × 70 kg = 63 mg
Bolus (10%) = 63 × 0.1 = 6.3 mg over 1 minute
Infusion (90%) = 63 × 0.9 = 56.7 mg over 60 minutes
Infusion rate = 56.7 mg/hour
Absolute Contraindications
- • Active internal bleeding
- • Intracranial hemorrhage (ICH)
- • Recent stroke (<3 months)
- • Recent major surgery (<14 days)
- • History of ICH or AVM
- • Platelet count <100,000
- • INR >1.7 or PT >15 seconds
- • Symptoms >4.5 hours
Monitoring Requirements
Vital Signs
Every 15 minutes during infusion
Neurological Exam
Every 15 minutes during infusion
Bleeding Assessment
Continuous monitoring required
Post-infusion CT
24 hours post-treatment
Emergency Actions
If Severe Bleeding Occurs:
- • Stop tPA infusion immediately
- • Emergency CT scan
- • Consider reversal agents
- • Activate massive transfusion protocol
Antidote Available:
Aminocaproic acid can be used to reverse tPA effects in emergencies
Understanding tPA for Stroke Treatment
What is tPA (Alteplase)?
tPA (tissue plasminogen activator) is a recombinant protein that dissolves blood clots by converting plasminogen to plasmin. Alteplase is the synthetic version used medically to treat acute ischemic stroke by restoring blood flow to affected brain tissue.
How Does tPA Work?
- •Activates fibrinolytic system
- •Converts plasminogen to plasmin
- •Plasmin dissolves fibrin clots
- •Restores cerebral blood flow
Dosing Protocol
Total Dose = 0.9 mg/kg (Max 90 mg)
- • Bolus: 10% of total dose over 1 minute
- • Infusion: 90% of total dose over 60 minutes
- • Bolus: Fixed 9 mg over 1 minute
- • Infusion: Fixed 81 mg over 60 minutes
Critical: Time window is 4.5 hours from symptom onset. Earlier treatment significantly improves outcomes.
Treatment Timeline
⚠️ Critical Medical Disclaimer
This calculator is designed for healthcare professionals only and should never be used as the sole basis for clinical decision-making. tPA administration is a high-risk procedure with potential for life-threatening complications including intracranial hemorrhage.
Always verify calculations independently, follow institutional protocols, and ensure proper patient screening before tPA administration. This tool does not replace clinical judgment, proper medical training, or adherence to current stroke treatment guidelines.
Emergency situations require immediate consultation with stroke specialists and adherence to evidence-based protocols.