DCI With Severe Portal Venous Gas Embolism After Cave Diving in a Diver With a PFO.

BACKGROUND

Cave diving involves prolonged bottom times and limited ascent routes, markedly increasing inert gas load and the risk of decompression illness (DCI). The presence of a patent foramen ovale (PFO) further elevates this risk.

CASE SUMMARY: A dive trainer developed DCI with severe portal venous air embolism after a 2.5-h cave dive. Symptoms included >20 min of mental confusion, skin rashes, and mild abdominal discomfort. Hyperbaric therapy improved his condition. Transesophageal echocardiography revealed a grade III, high-risk PFO. Following shared decision-making, percutaneous PFO closure was successfully performed. After 4 months of abstinence, the patient completed 150 subsequent dives without the recurrence of DCI. We continue to encourage adherence to all available measures to minimize nitrogen load.

DISCUSSION: Venous bubbles, including portal venous air embolism, cannot be reliably mitigated solely by PFO closure.

TAKE-HOME MESSAGE: Extreme nitrogen loading during cave diving with a high-risk PFO substantially increases the likelihood of DCI, underscoring the importance of nitrogen-minimizing strategies and the need for targeted PFO screening in divers with repeated high-exposure profiles.