Vertigo while scuba diving
A not so common question I get asked is "Why do I get dizzy when I ascend, even when I am on the surface, after a dive?”
Is this a sign of decompression sickness?"
A simple answer is YES and NO!
Let me take a few moments to clarify that response…..
Vertigo is the feeling that the world around you is moving, spinning or tilting whilst you are remaining essentially still. You may become off-balance, feel like you are going to faint, or feel light-headed, divers can also experience nausea and vomiting.
Vertigo is not uncommon amongst scuba divers, It is a symptom of vestibular system dysfunction
And divers experience vertigo with decreasing depth ascending from a dive.
Diver stress can trigger and worsen vertigo associated with anxiety.
Remember in your dive physics session- The greatest pressure changes from depth occur, as the diver descends or approaches shallower depths, IE. getting closer to the surface,
equalisation of the pressure in the middle ear space is very important. Divers often continue to descend, even whilst having difficulty with the equalisation process. During this process you are experiencing alternobaric vertigo, which is caused by unequal pressures between your middle-ear compartments.
The pressure differences are only minor where the pressure difference is communicated to the inner ear organs, resulting in vertigo.
. Vertigo is usually more common while a diver ascends. Not only are the symptoms uncomfortable, but they also can lead to catastrophic problems for the diver.
For example, when a person watches a 3-D movie in the theatre and momentarily perceives an illusion of moving or falling as the images rush past. However, frequent episodes of vertigo—whether lasting only for a few seconds or days on end—are a primary sign of a vestibular dysfunction, especially when linked to changes in head position. By contrast, dizziness can be a primary sign of a vestibular disorder
The body maintains balance with sensory information from three systems:
proprioception (touch sensors in the feet, trunk, and spine)
vestibular system (inner ear)
Sensory input from these three systems is integrated and processed by the brainstem. In response, feedback messages are sent to the eyes to help maintain steady vision and to the muscles to help maintain posture and balance.
Prevention of vertigo during diving requires careful, gradual and continuous equalization of the pressures within the middle ear throughout the dive.
when diving with a hood if one side of the hood seals over the ear tighter than the other.
A diver dives and has a mild cold, not enough to stop them diving due to equalisation. Diver ascends with a slight case of dizziness, doesn't seem too bad, later the diver experiences severe dizziness, and collapses on floor.
Diver is diagnosed as suffering DCS, transported to chamber and is treated.
The blockage clears itself and the diver is brought o the surface. Diver is Ok, walks, talks and is deemed Ok.
The Diver does not have any recordable DCS symptoms, so Yes, vertigo can be explained as DCS.