What Researchers Did
Researchers analyzed data from 2843 cases over 20 years to understand the link between central nervous system decompression sickness and gas bubbles in the veins.
What They Found
Out of 1108 altitude decompression sickness cases, 49 involved the central nervous system. Venous gas emboli (VGE) at any level (Grade 1 or higher) were found in 83.8% of non-neurological cases, but only 55.1% of central nervous system cases. High levels of VGE (Grade 4) were present in 48.8% of non-neurological cases, compared to 34.7% of central nervous system cases.
What This Means for Canadian Patients
This study suggests that detecting gas bubbles in the veins might not always predict central nervous system decompression sickness, a condition treated with hyperbaric oxygen therapy. For Canadian patients experiencing symptoms of decompression sickness, this implies that the absence of visible venous gas emboli does not rule out a serious central nervous system involvement. Prompt medical evaluation and appropriate treatment, including hyperbaric oxygen therapy, remain crucial regardless of bubble imaging results.
Canadian Relevance
This study covers decompression sickness, which is a Health Canada-recognized indication for hyperbaric oxygen therapy.
Study Limitations
The study's retrospective design and the finding that venous gas emboli were not present in about half of central nervous system decompression sickness cases limit the predictive value of bubble imaging.