What causes severe symptoms in the lungs during Caisson disease?

The correct answer is the formation of nitrogen bubbles, which is the primary pathological event in Decompression Sickness, commonly known as Caisson disease. This condition occurs when a diver ascends too quickly, leading to rapid reduction in pressure. Under high pressure, nitrogen, absorbed by the body tissues, forms bubbles as the pressure decreases during ascent. These nitrogen bubbles can cause significant damage within the lungs as they lead to pulmonary capillary obstruction, disrupt gas exchange, and provoke inflammatory reactions.

The clinical manifestations associated with Caisson disease, particularly in the lungs, can include symptoms like chest pain, cough, and respiratory distress, stemming from the release of these nitrogen bubbles into the pulmonary circulation. When nitrogen bubbles form, they can obstruct blood flow to lung tissues and trigger a cascade of physiological responses, including arterial gas embolism, which can compromise respiratory function.

The other options provided do not directly contribute to the severe respiratory symptoms observed in Caisson disease. While blood clots or arterial embolism could lead to lung symptoms, they are not the primary mechanism in this context. The presence of carbon dioxide bubbles is less relevant, as nitrogen is the gas primarily implicated in decompression sickness. Thus, the formation of nitrogen bubbles directly leads to the detrimental pulmonary effects seen in