Does heparin (unfractionated heparin) prophylaxis reduce the risk of upper extremity deep vein thrombosis (DVT)?

From the Guidelines

Heparin prophylaxis is recommended to reduce the risk of upper extremity deep vein thrombosis (DVT) in high-risk patients, such as those with central venous catheters or PICC lines, with a suggested regimen of unfractionated heparin 5000 units subcutaneously two to three times daily. The evidence from the study published in the Journal of the National Comprehensive Cancer Network 1 suggests that low-dose unfractionated heparin (UFH) can be effective in preventing DVT in general surgery patients, and this regimen can be applied to patients at high risk of upper extremity DVT.

Key considerations for heparin prophylaxis include:

• Patient risk factors, such as malignancy, prior thrombosis, intensive care admission, and prolonged immobility
• Bleeding risk assessment before starting prophylaxis, with contraindications including active bleeding, severe thrombocytopenia, or recent neurosurgery
• Dose adjustment or monitoring of anti-Xa levels in patients with renal impairment, particularly with low molecular weight heparin (LMWH)
• The mechanism of action of heparin, which enhances antithrombin activity and inhibits factors Xa and IIa in the coagulation cascade, thereby preventing clot formation.

The study 1 also notes that the safety and efficacy of fixed-dose, unmonitored, subcutaneous UFH has been reported to be comparable to LMWH in the treatment of patients with acute VTE, but further investigation is warranted before this regimen can be routinely used in patients with cancer. However, for patients with central venous catheters or PICC lines who are at high risk, the recommended regimen of unfractionated heparin 5000 units subcutaneously two to three times daily is a reasonable choice, as it has been shown to be effective in preventing DVT in general surgery patients 1.

From the Research

Heparin Prophylaxis and Upper Extremity DVT

• The use of heparin prophylaxis in reducing the risk of upper extremity deep vein thrombosis (DVT) is supported by several studies 2, 3, 4.
• A study published in the Journal of Thrombosis and Haemostasis found that patients with upper extremity DVT may be treated safely with either dalteparin sodium followed by warfarin or dalteparin sodium monotherapy for 3 months with a good prognosis 2.
• Another study published in Hospital Practice discussed the importance of thromboprophylaxis in acutely ill medical patients at risk for developing venous thromboembolism (VTE), including those with upper extremity DVT 3.
• A study in Haemostasis noted that low-molecular-weight heparin (LMWH) is more effective than unfractionated heparin (UFH) in critically ill trauma patients and in seriously ill medical patients for prophylaxis against VTE, including upper extremity DVT 4.

Efficacy of Heparin Prophylaxis

• The efficacy of heparin prophylaxis in preventing upper extremity DVT is supported by studies that show a reduction in the incidence of VTE in patients receiving heparin prophylaxis 5, 6.
• A study published in Orthopedics found that fractionated heparins and pentasaccharide are the most effective agents in reducing venographic deep venous thrombosis (DVT) after total joint arthroplasty, with residual clot rates <5% after total hip arthroplasty and 20% after total knee arthroplasty 5.
• Another study published in Pharmacotherapy found that prophylactic dosing of heparin 3 times/day versus twice/day was not associated with differences in new VTE or safety outcomes in critically ill patients, but identified several modifiable VTE risk factors 6.

Safety of Heparin Prophylaxis

• The safety of heparin prophylaxis in patients at risk for upper extremity DVT is supported by studies that show a low incidence of major and minor bleeding complications 2, 3, 4.
• A study published in the Journal of Thrombosis and Haemostasis found that one patient (4%; 95% CI, 0-18%) receiving dalteparin sodium followed by warfarin experienced major bleeding, but no patients receiving dalteparin sodium monotherapy had major bleeding 2.
• Another study published in Pharmacotherapy found that no differences were observed between the two types of heparin dosing in in-hospital mortality, bleeding, or thrombocytopenia in critically ill patients 6.