What is the recommended dosing for a heparin (unfractionated heparin) drip for therapeutic anticoagulation?

From the Guidelines

The recommended dosing for a therapeutic unfractionated heparin drip typically begins with an initial bolus of 80 units/kg, followed by a continuous infusion starting at 18 units/kg/hour. This dosing regimen is based on the most recent and highest quality evidence available, including the study by Raschke et al 1 and the guidelines from the American College of Chest Physicians 1. The infusion rate should then be adjusted based on activated partial thromboplastin time (aPTT) monitoring, with a target aPTT of 1.5-2.5 times the control value. Some key points to consider when administering heparin include:

• aPTT should be checked 6 hours after starting the infusion and 6 hours after any dose adjustment
• Once two consecutive aPTT values are therapeutic, monitoring can be reduced to daily checks
• Weight-based nomograms are commonly used to guide dose adjustments
• For patients with high bleeding risk or renal impairment, lower initial doses may be appropriate
• Adequate anticoagulation is crucial to prevent clot propagation while avoiding excessive bleeding risk
• Heparin works by binding to antithrombin III, enhancing its inhibitory effect on several coagulation factors, particularly thrombin and factor Xa, thus preventing clot formation and extension. It's also important to note that the dosing regimen may vary depending on the specific clinical context and patient population, such as those with cancer 1 or COVID-19 1. However, the general principles of heparin dosing and monitoring remain the same, and the initial bolus and infusion rates of 80 units/kg and 18 units/kg/hour, respectively, are widely accepted and supported by the evidence 1.

From the FDA Drug Label

The dosing recommendations in Table 1 are based on clinical experience be adjusted for the individual patient according to the results of suitable laboratory tests, the following dosage schedules may be used as guidelines: Table 1: Recommended Adult Full-Dose Heparin Regimens for Therapeutic Anticoagulant Effect *Based on 68 kg patient METHOD OF ADMINISTRATION FREQUENCY RECOMMENDED DOSE ... Continuous 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

The recommended dosing for a heparin drip for therapeutic anticoagulation is an initial dose of 5,000 units by intravenous injection, followed by a continuous infusion of 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.

• The dose should be adjusted according to the patient's coagulation test results, with the goal of maintaining an activated partial thromboplastin time (aPTT) of 1.5 to 2 times normal.
• Monitoring of aPTT, INR, platelet count, hematocrit, and occult blood in stool is necessary during the entire course of heparin therapy.
• The dosage may need to be adjusted for individual patients based on their clinical experience and laboratory test results.

From the Research

Heparin Drip Dosing Recommendations

The recommended dosing for a heparin (unfractionated heparin) drip for therapeutic anticoagulation is as follows:

• An initial intravenous bolus of 5000 units, followed by a maintenance dose of 30,000-40,000 units per 24 h by continuous intravenous infusion 3
• Alternatively, a weight-based dosing approach can be used, with a starting dose of 80 units/kg body weight bolus, and 18 units/kg per hour infusion 4
• For obese patients, aggressive weight-based dosing guidelines can help achieve prompt therapeutic anticoagulation, with a bolus dose of 80 units/kg and an initial continuous infusion of 18 units/kg/h 5, 4

Key Considerations

• The goal of heparin therapy is to achieve therapeutic anticoagulation, as measured by activated partial thromboplastin time (APTT) values 3, 4
• The APTT target range is typically 1.5-2.3 times the control value 3, 4
• Higher maximum doses and infusion rates may be necessary to achieve adequate anticoagulation in both obese and nonobese patients, without increasing the risk of bleeding 6
• Continuous subcutaneous infusion of heparin may be a viable alternative to intravenous therapy, with effective levels of anticoagulation achieved in all patients studied 7

Dosing Strategies

• Standard unfractionated heparin dosing: 60-unit/kg bolus (or maximum 4000 units) followed by an infusion of 12 units/kg/hour (or maximum 1000 units/hr) 6
• Aggressive weight-based UFH dosing strategy: 60-unit/kg bolus (or maximum 10,000 units) followed by an infusion of 12 units/kg/hr (or maximum 2250 units/hr) 6