Monitoring involves measurement of plasma levels of lepirudin (based on the whole blood ecarin clotting time test, with a clotting time of 350-400 µg/mL, corresponding to a plasma lepirudin level of 3.5-4.9 µg/mL):
(1) after the initial drug bolus
(2) every 15 minutes during the procedure
(3) to confirm an unexpectedly low or high activity level
Lepirudin is used:
(1) in the pump priming solution
(2) as an IV bolus before starting the procedure
(3) as an infusion during the procedure
The pump priming solution is treated with 0.2 mg per kg patient body weight.
The initial bolus to the patient is given before the anticipated start of the bypass. It is based on body weight:
initial IV bolus dose in mg =
= (0.25 * (body weight in kilograms))
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Lepirudin Level After the Initial Bolus
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Action
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> 2.5 µg/mL
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none (target level)
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<= 2.5 µg/mL
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administer an additional IV bolus of 10 mg
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During the procedure infusion danaparoid sodium at a rate of 0.5 mg per minute (30 mL per hour of a solution with 1 mg lepirudin per mL of 0.9% sodium chloride).
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Lepirudin Level During the Procedure
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Action
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> 4.5 µg/mL
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reduce infusion rate by 10 mL per hour
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3.5 - 4.5 µg/mL
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none (target level)
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< 3.5 µg/mL
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increase the infusion rate by 10 mL per hour
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The infusion of lepirudin is stopped 15 minutes before the anticipated end of the bypass.
After disconnection of the bypass pump 5 mg of lepirudin is added to the pump machine to avoid clot formation.
