Case report: intracardial gas bubbles in relation to altitude decompression chokes.

A case of altitude decompression chokes in a subject is described, which occurred unintentionally in an experimental series dealing with safe time intervals between diving and flying at 9,000 m of altitude. Before the development of the first signs of chokes, intracardial gas bubbles could be registered during 65 min and heavy showers of bubbles during 38 min with the precordial Doppler ultrasound technique. The intracardial bubbles and symptoms partly continued after recompression to surface pressure. After 10 min of hyperbaric oxygen treatment, the symptoms disappeared completely. The same subject, as well as others, did not develop chokes with similar durations of heavy showers of intracardial gas bubbles in other experiments.