Overview
This randomized assessor-masked trial will evaluate whether knee-high moderate graduated compression stockings reduce popliteal vein dilation during long-haul economy-class air travel to Bogota. Participants will be assigned to stockings or no stockings and will undergo bilateral ultrasound before flight, within 2 hours after arrival, and at 24 and 48 hours. The primary outcome is the between-group difference in change in mean bilateral popliteal vein diameter from preflight baseline to arrival.
Description
Eligible economy-class travelers will be randomized before departure. The intervention group will wear properly fitted knee-high graduated compression stockings from approximately 1 hour before boarding through the arrival ultrasound; the control group will not use lower-limb compression. A masked ultrasound assessor will obtain standardized bilateral diameter and cross-sectional-area measurements before flight and at arrival, 24 hours, and 48 hours. Adherence, movement, hydration, symptoms, and skin effects will be recorded. Intention-to-treat mixed models will estimate immediate and persistent treatment effects.
Eligibility
Inclusion Criteria:
- Age 18 to 65 years.
- Economy-class commercial itinerary to Bogota with at least 4 hours of total airborne time.
- No clinical indication that mandates or prohibits compression stockings.
- Ability to obtain the assigned stocking before boarding and wear it as instructed.
- Standardized preflight and postarrival ultrasounds completed before surgery.
- Written informed consent.
Exclusion Criteria:
- Current deep venous thrombosis, therapeutic anticoagulation, or severe peripheral arterial disease.
- Significant lower-limb skin disease, ulceration, neuropathy, or deformity preventing safe stocking use.
- Pregnancy.
- Planned use of another compression device during the flight.
- Surgery or major intravenous fluid therapy before completion of the 48-hour examination.
- Inability to complete preflight ultrasound or follow assigned treatment.
