2 DOSAGE AND ADMINISTRATION
2.1 Preparation for Administration
Confirm the choice of the correct Heparin Sodium Injection vial or cartridge prior to administration of the drug to a patient [see Warnings and Precautions (5.1)]. Heparin Sodium Injection, products must not be confused with "catheter lock flush" products. To lessen this risk for a cartridge, a red cautionary statement has been added to the cartridge and box/bin. Read the cautionary statement and confirm that you have selected the correct medication and strength.
When heparin is added to an infusion solution for continuous intravenous administration, invert the container repeatedly to ensure adequate mixing and prevent pooling of the heparin in the solution.
Inspect parenteral drug products visually for particulate matter and discoloration prior to administration, whenever solution and container permit. Use only if solution is clear and the seal is intact. Do not use if solution is discolored or contains a precipitate.
Administer Heparin Sodium Injection by intermittent intravenous injection, intravenous infusion, or deep subcutaneous (intrafat, i.e., above the iliac crest or abdominal fat layer) injection. Do not administer Heparin Sodium Injection by intramuscular injection because of the risk of hematoma at the injection site [see Adverse Reactions (6)].
2.2 Laboratory Monitoring for Efficacy and Safety
Adjust the dosage of Heparin Sodium Injection according to the patient's coagulation test results. Dosage is considered adequate when the activated partial thromboplastin time (aPTT) is 1.5 to 2 times normal or when the whole blood clotting time is elevated approximately 2.5 to 3 times the control value. When initiating treatment with Heparin Sodium Injection by continuous intravenous infusion, determine the coagulation status (aPTT, INR, platelet count) at baseline and continue to follow aPTT approximately every 4 hours and then at appropriate intervals thereafter. When the drug is administered intermittently by intravenous injection, perform coagulation tests before each injection during the initiation of treatment and at appropriate intervals thereafter. After deep subcutaneous (intrafat) injections, tests for adequacy of dosage are best performed on samples drawn 4 to 6 hours after the injection.
Periodic platelet counts, and hematocrits are recommended during the entire course of heparin therapy, regardless of the route of administration.
2.3 Therapeutic Anticoagulant Effect With Full-Dose Heparin
The dosing recommendations in Table 1 are based on clinical experience. Although dosages must be adjusted for the individual patient according to the results of suitable laboratory tests, the following dosage schedules may be used as guidelines:
|METHOD OF ADMINISTRATION||FREQUENCY||RECOMMENDED DOSE|
[based on 150 lb (68 kg) patient]
|Deep, Subcutaneous (Intrafat) Injection||Initial dose||5,000 units by intravenous injection, followed by 10,000 to 20,000 units of a concentrated solution, subcutaneously|
|A different site should be used for each injection to prevent the development of massive hematoma||Every 8 hours |
Every 12 hours
|8,000 to 10,000 units of a concentrated solution|
|15,000 to 20,000 units of a concentrated solution|
|Intermittent Intravenous Injection||Initial dose||10,000 units, either undiluted or in 50 to 100 mL of 0.9% Sodium Chloride Injection, USP|
|Every 4 to 6 hours||5,000 to 10,000 units, either undiluted or in 50 to 100 mL of 0.9% Sodium Chloride Injection, USP|
|Intravenous Infusion||Initial dose||5,000 units by intravenous injection|
|Continuous||20,000 to 40,000 units/24 hours in 1,000 mL of 0.9% Sodium Chloride Injection, USP (or in any compatible solution) for infusion|
2.4 Pediatric Use
Use preservative-free Heparin Sodium Injection in neonates and infants [see Warnings and Precautions (5.4)].
There are no adequate and well controlled studies on heparin use in pediatric patients. Pediatric dosing recommendations are based on clinical experience. In general, the following dosage schedule may be used as a guideline in pediatric patients:
|Initial Dose||75 to 100 units/kg (Intravenous bolus over 10 minutes)|
|Maintenance Dose||Infants: 25 to 30 units/kg/hour;|
|Infants <2 months have the highest requirements (average 28 units/kg/hour)|
|Children >1 year of age: 18 to 20 units/kg/hour;|
|Older children may require less heparin, similar to weight-adjusted adult dosage|
|Monitoring||Adjust heparin to maintain APTT of 60 to 85 seconds, assuming this reflects an anti-Factor Xa level of 0.35 to 0.70|
2.5 Cardiovascular Surgery
Patients undergoing total body perfusion for open-heart surgery should receive an initial dose of not less than 150 units of heparin sodium per kilogram of body weight. Frequently, a dose of 300 units per kilogram is used for procedures estimated to last less than 60 minutes, or 400 units per kilogram for those estimated to last longer than 60 minutes.
2.6 Low-Dose Prophylaxis of Postoperative Thromboembolism
The most widely used dosage has been 5,000 units 2 hours before surgery and 5,000 units every 8 to 12 hours thereafter for 7 days or until the patient is fully ambulatory, whichever is longer. Administer the heparin by deep subcutaneous injection (intrafat, i.e., above the iliac crest or abdominal fat layer, arm, or thigh) with a fine (25 to 26-gauge) needle to minimize tissue trauma.
2.7 Blood Transfusion
Add 450 to 600 USP units of Heparin Sodium per 100 mL of whole blood to prevent coagulation. Usually, 7,500 USP units of heparin sodium are added to 100 mL of 0.9% Sodium Chloride Injection, USP (or 75,000 USP units per 1,000 mL of 0.9% Sodium Chloride Injection, USP) and mixed; from this sterile solution, 6 mL to 8 mL are added per 100 mL of whole blood.
2.8 Converting to Warfarin
To ensure continuous anticoagulation when converting from Heparin Sodium Injection to warfarin, continue full heparin therapy for several days until the INR (prothrombin time) has reached a stable therapeutic range. Heparin therapy may then be discontinued without tapering [see Drug Interactions (7.1)].
2.9 Converting to Oral Anticoagulants other than Warfarin
For patients currently receiving intravenous heparin, stop intravenous infusion of Heparin Sodium immediately after administering the first dose of oral anticoagulant; or for intermittent intravenous administration of heparin sodium, start oral anticoagulant 0 to 2 hours before the time that the next dose of heparin was to have been administered.