What is the preparation and administration protocol for Tirofiban (Aggrastat) in a 60kg patient undergoing primary Percutaneous Coronary Intervention (PCI)?

Tirofiban (Aggrastat/Aggribloc) Preparation and Administration for Primary PCI in a 60kg Patient

For a 60kg patient undergoing primary PCI, tirofiban should be administered as a 25 mcg/kg IV bolus over 3-5 minutes, followed by a maintenance infusion of 0.15 mcg/kg/min for up to 18 hours. 1, 2

Preparation of Tirofiban from Aggribloc Vial

Step 1: Calculate the Required Doses

• Bolus dose calculation: 25 mcg/kg × 60 kg = 1,500 mcg (1.5 mg)
• Maintenance infusion calculation: 0.15 mcg/kg/min × 60 kg = 9 mcg/min (0.54 mg/hour)

Step 2: Prepare the Bolus Dose

1. Using the 250 mL premixed bag (50 mcg/mL concentration):
   • Bolus volume = 1,500 mcg ÷ 50 mcg/mL = 30 mL
2. Administer the 30 mL bolus via IV pump over 3-5 minutes 2

Step 3: Prepare the Maintenance Infusion

1. Using the same 250 mL premixed bag:
   • Infusion rate = 9 mcg/min ÷ 50 mcg/mL = 0.18 mL/min (10.8 mL/hour)
2. Set the IV pump to deliver 10.8 mL/hour immediately following the bolus administration 2

Administration Protocol

1. Initial assessment: Confirm the patient requires primary PCI and has no contraindications to tirofiban (active bleeding, history of bleeding diathesis, severe thrombocytopenia, or hypersensitivity to tirofiban) 2

2. Pre-medication: Ensure the patient has received:

   • Aspirin (162-325 mg loading dose)
   • P2Y12 inhibitor (clopidogrel 600 mg, prasugrel 60 mg, or ticagrelor 180 mg) 1

3. Anticoagulation: Administer unfractionated heparin (UFH):

   • If using tirofiban with UFH: 50-70 U/kg IV bolus to achieve ACT of 200-250 seconds 1

4. Tirofiban administration:

   • Administer the bolus dose (30 mL) over 3-5 minutes via IV pump
   • Immediately start the maintenance infusion at 10.8 mL/hour
   • Continue infusion for up to 18 hours at the discretion of the physician 1, 2

5. Dose adjustment for renal impairment:

   • If creatinine clearance ≤60 mL/min: Maintain the same bolus dose (25 mcg/kg) but reduce the maintenance infusion by 50% to 0.075 mcg/kg/min 2
   • For a 60kg patient with renal impairment: Infusion rate = 4.5 mcg/min = 5.4 mL/hour

Monitoring and Precautions

1. Monitor for bleeding: Most common complication is bleeding, particularly at arterial access sites 2

2. Monitor platelet counts: Check platelets approximately 6 hours after starting treatment and daily thereafter 2

   • If platelet count decreases to <90,000/mm³, discontinue tirofiban and heparin

3. Drug compatibilities: Tirofiban can be administered in the same IV line as heparin, atropine, dobutamine, dopamine, epinephrine, famotidine, furosemide, lidocaine, midazolam, morphine, nitroglycerin, potassium chloride, and propranolol 2

   • Do NOT administer through the same IV line as diazepam
   • Do NOT add other drugs directly to the tirofiban bag

4. Duration of therapy: Continue infusion for up to 18 hours at the physician's discretion 1, 2

Clinical Considerations

• Tirofiban has been shown to be effective in reducing ischemic complications in patients undergoing primary PCI for STEMI 1, 3
• The high-dose bolus regimen (25 mcg/kg) provides more rapid and complete platelet inhibition than the older lower-dose regimens 3, 4
• Tirofiban's effect is reversed within hours after completion of the infusion, unlike abciximab which has a considerably longer effect 3

Remember that tirofiban should be used with caution in patients at high risk of bleeding, and is contraindicated in patients with active internal bleeding, history of bleeding diathesis, or severe hypersensitivity to tirofiban 2.