Decompression Illness and Associated Physiological Responses

Decompression illness encompasses a spectrum of disorders arising when inert gas bubbles form in tissues and blood during or after reduction in ambient pressure. Mechanical obstruction by gas bubbles can precipitate vascular occlusion, endothelial injury and activation of coagulation cascades. Concurrent biochemical responses include oxidative stress, complement activation and release of inflammatory mediators. Pulmonary manifestations range from immersion pulmonary oedema to acute respiratory distress, while neurological involvement may lead to sensory disturbances, motor deficits or cognitive impairment. Risk factors such as dive depth, ascent rate, physical exertion and individual susceptibility combine to determine the severity of decompression stress. Advances in molecular profiling have revealed key roles for microparticles, cytokines and vasoactive peptides in modulating bubble-induced injury. Translational applications focus on optimised decompression schedules, hyperbaric oxygen therapy and pharmacological interventions aimed at blunting oxidative and inflammatory pathways.

Research from Nature Portfolio

Recent investigations have shown that predisposing injuries can exacerbate decompression outcomes. In experimental models, animals subjected to radiation before hyperbaric decompression exhibited significantly higher mortality and more severe pulmonary lesions. This arose from up-regulation of angiotensin-converting enzyme expression and elevated angiotensin II levels, which amplified oxidative stress and activated the PI3K/AKT signalling pathway in lung tissue. These findings point to the angiotensin axis as a potential therapeutic target to mitigate tissue damage in complex decompression scenarios.

Decompression Illness and Associated Physiological Responses publication trend

The graph below shows the total number of articles in decompression illness and associated physiological responses across all publications each year (not limited to Nature Index journals).

Technical terms

Decompression sickness (DCS): A condition caused by rapid drop in ambient pressure leading to formation of gas bubbles in tissues and blood.

Nitrogen bubble nucleation: The initial phase in which dissolved nitrogen comes out of solution and forms microscopic bubbles.

Endothelial dysfunction: Impairment of the inner lining of blood vessels, often triggered by mechanical stress or inflammatory mediators.

Immersion pulmonary oedema (IPE): Accumulation of fluid in the lungs induced by changes in hydrostatic and vascular pressures during immersion.

Angiotensin II: A vasoactive peptide that promotes vasoconstriction, inflammation and oxidative stress through activation of cell-signalling pathways.

References

1. Characterizing Immersion Pulmonary Edema (IPE): A Comparative Study of Military and Recreational Divers. Sports Medicine - Open (2023).
2. Dissolved gases from pressure changes in the lungs elicit an immune response in human peripheral blood. Bioengineering & Translational Medicine (2024).
3. Elevations of Extracellular Vesicles and Inflammatory Biomarkers in Closed Circuit SCUBA Divers. International Journal of Molecular Sciences (2023).
4. Effect of angiotensin II on irradiation exacerbated decompression sickness. Scientific Reports (2023).