Description

Ahmed Y, Lindholm P, Bartlett N, Tripp M, Boswell G, Volk C. A Non-Invasive Gas Exchange Monitor

To Assess Swimming-Induced Pulmonary Edema. Undersea Hyperb Med. 2026 Second Quarter;

53(2):343-348.

Introduction: Swimming-induced pulmonary edema (SIPE) occurs in physically demanding

environments. SIPE has been identified among U.S. Naval Special Warfare (NSW) candidates, risking

trainees' lives or, less severely, preventing them from completing training. Diagnosis is based on clinical

examination and chest X-ray. The MediPines gas exchange monitor AGM-100 is a noninvasive diagnostic

tool approved by the FDA and used in hospital settings. This study aimed to assess noninvasive

physiological parameters and evaluate the use of the AGM-100 in NSW candidates with SIPE.

Methods: In this observational study, eighteen subjects were tested (nine with confirmed SIPE). Data on

a noninvasive surrogate for oxygen deficit, based on end-tidal oxygen (EtO2),carbon dioxide (EtCO2), and

SpO2 were collected. Chest X-rays (CXR) were graded for interstitial and airspace edema.

Results: Subjects with confirmed SIPE displayed an oxygen deficit (28.1 ± 12.9 mm Hg), while eight of

nine subjects without SIPE did not (3.1 ± 8.79 mm Hg, p < 0.001). There were no differences in EtCO2. SpO2

was lower in individuals with confirmed SIPE (95.1 ± 2.23%) compared to controls/unconfirmed SIPE (98.1

± 0.31%, p-value < 0.0001). The group with the oxygen deficit had a correspondingly worse edema grade

on CXR.

Discussion: These limited results showed a possible correlation between O2 deficit and SIPE, while the

AGM-100 performed reliably in this prehospital setting. Future higher-powered studies are needed to

substantiate these findings and the AGM-100's utility, possibly extending to other environments, such as

combat field hospitals, for rapid diagnosis and severity assessment of pulmonary edema.

Keywords: gas exchange; physiology; swimming-induced pulmonary edema