Can a patient with new onset Deep Vein Thrombosis (DVT), who is hemodynamically stable and fully anticoagulated, still fly on an airplane?

From the Guidelines

Flying is not recommended for patients with new onset Deep Vein Thrombosis (DVT) for at least 2-4 weeks after diagnosis and initiation of treatment, even if they are hemodynamically stable and fully anticoagulated. This recommendation is based on the risk of clot propagation or embolization remaining elevated despite anticoagulation therapy, as highlighted in the context of travel-related risks for venous thromboembolism 1.

Key Considerations for Travel

When travel is unavoidable, several precautions can be taken to minimize risks:

• Continue prescribed anticoagulation regimen without interruption, which could include direct oral anticoagulants (DOACs) like apixaban or rivaroxaban, or warfarin with appropriate monitoring and bridging therapy if necessary.
• Stay well-hydrated and avoid alcohol consumption during flights.
• Perform frequent calf muscle exercises and walk around the cabin every 1-2 hours to reduce immobility.
• Wear properly fitted compression stockings (20-30 mmHg) to help prevent clot formation.

Risks Associated with Flying

The primary concern with flying for patients with DVT is the increased risk of clot extension or pulmonary embolism due to prolonged immobility and reduced cabin pressure, as discussed in the context of travel-related venous thrombosis risks 1. However, this risk decreases significantly after the initial treatment period when the clot has stabilized.

General Recommendations

• For patients with a history of thrombosis or active cancer, preventive measures such as frequent rest breaks, sufficient fluid intake, and thromboprophylaxis are recommended for all modes of travel 1.
• The overall absolute incidence of symptomatic venous thromboembolism (VTE) in healthy individuals within the first month after a flight lasting >4 hours is approximately 1 in 4,600 flights, and this risk increases with longer flight durations 1.

Given the potential risks, it is crucial for patients with new onset DVT to consult their healthcare provider before planning any travel, especially by air, to assess their individual risk and receive personalized advice on how to minimize these risks.

From the Research

Flight Restrictions for Patients with New Onset DVT

• Patients with new onset Deep Vein Thrombosis (DVT) who are hemodynamically stable and fully anticoagulated may still be able to fly on an airplane, but certain precautions should be taken.
• According to the study 2, the risk of travel-related thrombosis is higher in individuals with pre-existing risk factors for the development of VTE, and assessment of risk should be made on an individual basis.
• The study 2 also recommends that travelers at the highest risk of travel-related thrombosis undertaking journeys of >3 h should wear well-fitted below-knee compression hosiery.

General Guidelines for Travel-Related VTE

• Long duration travel is a weak risk factor for the development of venous thromboembolism (VTE) 2.
• The incidence of VTE after flights of >4 h is 1 in 4656, and for flights of more than 8 h in low and intermediate risk flyers is around 0.5% 2.
• Severe symptomatic pulmonary embolism in the period immediately after travel is extremely rare after flights of <8 h 2.

Anticoagulation Therapy and Travel

• Patients with DVT or pulmonary embolism are recommended to receive anticoagulation for acute treatment and secondary prevention of venous thromboembolism (VTE) 3.
• The decision to stop anticoagulants at 3 months or to treat indefinitely is dominated by the long-term risk of recurrence, and secondarily influenced by the risk of bleeding and by patient preference 4.
• According to the study 5, all patients with acute VTE should receive oral anticoagulant treatment for three months, and at the end of this treatment period, physicians should decide for withdrawal or indefinite anticoagulation.

Precautions for Patients with New Onset DVT

• Patients with new onset DVT who are planning to travel by air should consult their physician to assess their individual risk of travel-related thrombosis and to discuss any necessary precautions 2.
• Maintaining mobility during long flights may help prevent VTE, and wearing well-fitted below-knee compression hosiery may be recommended for high-risk travelers 2.