NCT06984120

Increased Extravascular Lung Water in Asymptomatic Open-water Swimmers

• Status: Completed
• Phase: —
• Study type: Observational
• Enrollment: 609 (actual)
• Sponsor: Dalarna County Council, Sweden · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Accepted

Summary

Previous studies suggest that increased extravascular lung water might be found in open water swimmers without respiratory symptoms. This study aims to investigate a large number of asymptomatic individuals after an open-water swimming race to assess the prevalence of increased extravascular lung water in asymptomatic open-water swimmers.

Detailed description

Swimming-induced pulmonary edema (SIPE) can occur during open-water swimming. The pathophysiological mechanisms are still partly unknown, but central pooling of blood volume and peripheral vasoconstriction have been suggested as important factors. SIPE is characterized by acute onset of dyspnea and cough, sometimes with excessive sputum and hemoptysis. The condition usually resolves spontaneously, but medical attention can be required in more severe cases. Previous studies suggest that SIPE is diagnosed by clinical symptoms, decreased peripheral oxygen saturation and signs of pulmonary edema on lung ultrasound. Interestingly, signs of increased extravascular lung water have been found in divers without respiratory symptoms. There are no similar studies regarding open-water swimmers. This study aims to investigate a large number of swimmers without respiratory symptoms after finishing an open-water swimming race. Prevalence and amount of increased extravascular lung water after swimming will be assessed by lung ultrasound. In addition, individual baseline factors and information about the race associated with increased extravascular lung water will be evaluated. This study will provide better understanding of the pathophysiological mechanism of SIPE.

Conditions

• Pulmonary Edema - Acute
• Extravascular Lung Water

Interventions

Type	Name	Description
DIAGNOSTIC_TEST	Lung ultrasound	Four chest regions for both lungs are scanned by lung ultrasound; a positive region defined by the presence of three or more B-line artifacts. Bilateral or unilateral presence of two or more positive regions define positive interstitial syndrome.
DIAGNOSTIC_TEST	Peripheral oxygen saturation	Peripheral oxygen saturation measured by non-invasive pulse oxymetry
DIAGNOSTIC_TEST	Lung auscultation	Clinical auscultation of lungs
DIAGNOSTIC_TEST	Body temperature	Body temperature measured by ear thermometer.

Timeline

• Start date: 2025-06-29
• Primary completion: 2025-07-30
• Completion: 2025-07-30
• First posted: 2025-05-22
• Last updated: 2026-02-18

Locations

2 sites across 1 country: Sweden