Cerebral arterial gas embolism in a professional diver with a persistent foramen ovale

A 33-year-old, male professional scallop diver diving on the Outer Hebrides in Scotland rapidly developed symptoms of cerebral arterial gas embolism following a provocative dive with possibly a fast ascent. During transfer by helicopter to the mainland for treatment, his symptoms improved on surface oxygen. He was recompressed on a Royal Navy Treatment Table 62 (RN TT62) with complete resolution. Just over six weeks later, again diving on the Outer Hebrides and after adopting more conservative diving practices, he developed symptoms and signs of vestibular decompression sickness after a problem-free dive, with dizziness, poor co-ordination and gait, nausea and vomiting, and rotational vertigo. He was again transported to the mainland for recompression treatment. He received an extended RN TT62 and required five further Comex 12 (223 kPa) hyperbaric oxygen treatments over the following three days before he was symptom free. A 4 mm persistent foramen ovale (PFO) was subsequently diagnosed and he underwent successful closure of the defect with Amplatzer device and returned to commercial diving a year later.