Relation between right-to-left shunts and spinal cord decompression sickness in divers

Area of Science:

• Diving Medicine
• Cardiovascular Physiology
• Neurology

Background:

• The link between right-to-left shunting (RLS) and spinal cord decompression sickness (DCS) is not fully understood.
• A patent foramen ovale may increase the risk of upper spinal cord DCS in divers.

Purpose of the Study:

• To determine the prevalence of RLS in divers with spinal cord DCS.
• To compare RLS prevalence in DCS divers versus healthy diving controls.
• To investigate the association between RLS and the location of spinal cord lesions.

Main Methods:

• Transcranial doppler ultrasonography was used to assess RLS.
• 49 divers with spinal cord DCS and 49 diving controls participated.
• Statistical analysis was performed to compare RLS prevalence and lesion sites.

Main Results:

• The prevalence of large RLS was significantly higher in divers with spinal cord DCS compared to controls (OR, 3.6).
• RLS was not associated with cervical spinal cord DCS (OR, 1.1).
• A significant association was found between large RLS and thoracolumbar spinal cord DCS (OR, 6.9).

Conclusions:

• Divers with hemodynamically significant RLS have an elevated risk of spinal cord DCS.
• The risk is particularly pronounced for DCS affecting the thoracolumbar region of the spinal cord.