What are the flying precautions for patients with deep vein thrombosis (DVT)?

Flying Precautions for Patients with Deep Vein Thrombosis (DVT)

For patients with DVT, frequent ambulation, calf muscle exercises, sitting in an aisle seat, and wearing properly fitted below-knee compression stockings providing 15-30 mmHg pressure are strongly recommended during flights, especially those longer than 4 hours. 1

Risk Assessment

Patients with DVT are at significantly increased risk of travel-related thrombotic complications. The risk factors include:

• History of previous DVT or pulmonary embolism
• Recent surgery or trauma (within 1 month)
• Active malignancy
• Limited mobility
• Severe obesity
• Known thrombophilic disorder 1

Travel itself is a weak risk factor for VTE, with an incidence of 1 in 4,656 for flights over 4 hours, but this risk increases substantially in those with pre-existing DVT or risk factors 2.

Recommended Preventive Measures

For All DVT Patients:

1. Mobility Maintenance:

   • Frequent walks in the cabin every 1-2 hours 1
   • Calf muscle exercises when seated 1
   • Request an aisle seat to facilitate movement 1
   • Flex and extend ankles periodically while seated 3

2. Compression Stockings:

   • Wear properly fitted, below-knee compression stockings providing 15-30 mmHg pressure 1
   • Put on stockings 2-3 hours before the flight 1
   • Ensure proper fit - stockings that are too tight can restrict circulation and potentially worsen the condition 1

3. Hydration:

   • Increase fluid intake by 0.5-1 liter per day during travel 1
   • Avoid alcohol and excessive caffeine consumption 1, 3

Pharmacological Considerations:

• Anticoagulation: Patients should continue their prescribed anticoagulation therapy during travel 1
• Prophylactic Anticoagulants: For high-risk patients, anticoagulants are preferred over anti-platelet drugs if pharmacological prophylaxis is deemed necessary 2
• Aspirin: Not recommended specifically for DVT prevention during travel 1

Warning Signs Requiring Immediate Attention

Monitor for:

• Unilateral leg swelling (may indicate new or worsening DVT) 3
• Pain, redness, warmth, or tenderness in the leg 3
• Shortness of breath or chest pain (may indicate pulmonary embolism) 1

Important Considerations and Pitfalls

• Timing of Travel: VTE may be attributable to travel if it occurs up to 8 weeks following the journey 2
• Stockings Fit: Improperly fitted compression stockings can potentially worsen circulation and increase DVT risk 1
• Dehydration: While maintaining good hydration is recommended, there is limited evidence directly linking dehydration to travel-associated VTE 2
• Self-medication: Avoid self-medicating with diuretics without medical supervision as this can lead to electrolyte imbalances 3

Special Circumstances

For patients with severe symptoms or high-risk features (multiple previous DVTs, recent DVT within 1 month), consider:

• Consulting with a healthcare provider before travel to assess if additional prophylactic measures are needed 1
• Potentially postponing non-essential long-distance travel until DVT is adequately treated and stabilized

The risk of travel-related thrombosis is highest for flights longer than 8 hours, with risk increasing by approximately 18% for each additional 2 hours of flight duration 1. Therefore, longer flights warrant more vigilant adherence to these precautions.