The indispensable
- Wear loose clothing;
- Stay hydrated during the flight (non-alcoholic drinks);
- Frequently move your legs and move around the plane;
- Limit the use of hypnotics;
- Wear a class 2 mid-thigh elastic compression stocking (if there is a risk factor for thrombosis);
- Injectable anticoagulants (LMWH or fondaparinux) may be considered off-label in very high-risk travelers, after medical evaluation.
The recommended preventative measures
- Wear loose clothing;
- Stay hydrated during the flight (non-alcoholic drinks);
- Move your legs frequently, move around the plane and follow the exercise programs offered by some airlines during the flight, which can be done without leaving your seat;
- … Which implies: limiting the use of hypnotics;
- Wear class 2 elastic compression stockings (mid-thigh is more comfortable than below the knee) (ankle pressure of 15 to 30 mm Hg) in the presence of at least one risk factor for thrombosis.
Although the effectiveness of compression in preventing DVT is not clearly established, it at least reduces edema in the lower limbs.
Use of anticoagulants:
Low molecular weight heparins or fondaparinux (factor X inhibitor) do not have a validated indication but are sometimes prescribed, off-label, at prophylactic doses or in cases of very high risk, in addition to other preventive measures (table below: prescription methods).
Aspirin is not recommended for this indication. The role of direct oral anticoagulants (DOACs), such as rivaroxaban or apixaban, is not defined.
The use of anticoagulants justifies careful verification of contraindications, and in particular adaptation to renal function.
| Main dosage regimens used: One subcutaneous injection 2 to 4 hours before the flight (if clearance ≥ 30 ml/min); plan the dose for the return trip in international units (IU) | |
| Dalteparin | 5000 IU |
| Enoxaparin | 40 mg |
| Tinzaparine | 4500 IU |
| Nadroparin | 2500 IU |
| Fondaparinux | 2,5 mg (not recommended for pregnant or breastfeeding women) |
In practice, preventing the risk of venous thrombosis may rely on additional measures depending on the type and number of risk factors (RFs):
| Risk assessment | Flight duration ≥ 4 hours |
| No FDR | Leg movements, regular walking, good hydration |
| Presence of FDR | + Class 2 compression stockings or socks |
| High risk level: personal history of unprovoked or travel-related VTE, high-risk surgery or recent trauma, active cancer, combination of 2 risk factors | + Evaluate the role of prophylactic treatment with LMWH (or DOAC) |
Source: Guide to Health Recommendations from the High Council for Public Health for Travellers
