What is a common risk associated with prolonged travel that increases the risk of PE?

Prolonged inactivity is recognized as a significant risk factor for the development of pulmonary embolism (PE) during extended travel. The mechanism behind this is that when a person remains inactive for long periods, especially during sitting, it can lead to the stasis of blood in the lower extremities. This stasis can result in the formation of deep vein thrombosis (DVT)—a blood clot in the deep veins, often in the legs. If a part of this clot breaks loose, it can travel through the bloodstream to the lungs, causing a PE.

In contrast, while fatigue, dehydration, and motion sickness can be common complaints during prolonged travel, they do not have the same direct physiological relationship to thrombus formation and the consequent risk of PE. Fatigue might affect overall well-being, dehydration can influence blood viscosity, and motion sickness typically involves gastrointestinal symptoms rather than vascular complications. Thus, prolonged inactivity stands out as the primary concern related to increased risk for PE.