Posology : מינונים

4.2 Posology and method of administration
Dosage
Heparin sodium must be individually dosed.
The dosage depends on the coagulation nature and course of the disease, patient’s response, adverse reactions, patient’s weight and age. Differences in sensitivity to heparin and a possible change in heparin tolerance during the course of treatment need to be considered.

Treatment of venous or arterial thromboembolic disorders Continuous intravenous administration is recommended if there are clots in blood vessels.

Dosage in adults
Generally start with 5000 IU heparin sodium as an intravenous bolus, followed by a continuous infusion of 1000 IU heparin sodium per hour using an infusion pump.

Dosage in children
Initially 50 IU/kg body weight, then 20 IU/kg body weight per hour.
If a continuous intravenous infusion is not possible, other heparin product may be used as subcutaneously alternative.
Therapy Monitoring
Close monitoring of therapy accompanied by assay of coagulation parameters is absolutely essential in all cases. Monitoring of therapy and dose adjustment are generally based on activated partial thromboplastin time (aPTT), which should be around 1.5-2.5 times the normal value. It is recommended that the aPTT be checked 1-2 hours, 6 hours, 12 hours and 24 hours after the start of treatment in the case of continuous intravenous heparin administration.
• Treatment of venous thromboembolism
Initially, 5000 IU heparin sodium should be administered intravenously as a bolus, followed by an intravenous infusion of generally 1000 IU heparin sodium per hour. The dosage should be adjusted according to the aPTT values, aiming to prolong the aPTT to 1.5-2.5 times the initial value (within the first 24 hours if possible).
The treatment should take place for at least 4 days or be continued until adequate oral anticoagulation has been achieved.

• As part of the treatment of unstable angina and non–Q-wave myocardial infarction
In general, 5000 IU heparin sodium as an intravenous bolus, followed by a continuous infusion of 1000 IU per hour. The dose is based on the aPTT, which should be prolonged to 1.5-2.5 times the normal value.
Heparin sodium should be administered for at least 48 hours.
• As concomitant therapy in thrombolysis with fibrin-specific thrombolytics (e.g. r-tPA) for the treatment of acute myocardial infarction Initially, 5000 IU heparin sodium as an intravenous bolus, followed by an intravenous infusion of 1000 IU per hour.
The infusion should be adjusted according to aPTT values to prolong them to about 1.5-2.5 times the initial value. Heparin sodium should be given for 48 hours.
The exact dosage of the concomitant heparin therapy depends on the type of thrombolytic and should be undertaken according to the data on the individual thrombolytic agents.
It is important to ensure accurate monitoring of the coagulation status in all cases.

Anticoagulation in treatment or surgery with an extracorporeal circulation
• Haemodialysis
Individual dosage depending on the results of the coagulation tests and type of machine.

• Heart/lung machine
The dosage depends on the type of heart/lung machine and the length of the operation and should be managed individually.

Method and duration of administration
For intravenous injection or intravenous infusion after dilution.
Note:
To minimise disruption of lymph drainage, Pharepa 25,000 IU/5 ml should be administered into the upper arm in patients with surgical clearance of lymph nodes in the abdominal/urogenital regions.
Note:
As heparin is bound by platelet components (PF4), as a result of which the effect is neutralised, blood taken for coagulation tests and mixed with citrate should be centrifuged and decanted as soon as possible after sampling in order to separate blood cells and blood plasma.
The treating physician decides on the duration of administration.
Regular monitoring of the activated partial thromboplastin time (aPTT) and platelet count are necessary with heparin therapy.