DescriptionVertigo during or after diving is a common symptom of middle-ear or inner-ear injury. It is often associated with nausea and in severe cases vomiting. If vertigo happens underwater, the diver may not be able to tell which way is up; panic and vomiting may cause choking and drowning. On land, the patient may not be able to sit or stand
There are various causes of vertigo. In diving, it is most often caused by inner-ear barotrauma. It can also occur from stimulation of one side and not the other, such as when the pressure difference in only one ear equalizes (alternobaric vertigo) or when cold water enters one ear but not the other (caloric vertigo). This type of vertigo disappears as the condition equalizes and leaves no lasting effects except that the associated disorientation, nausea and vomiting while underwater may contribute to diving accidents.
Vertigo is an acute symptom of vestibular injury that may be associated with other symptoms, some of which may become chronic. Symptoms may include imbalance and spatial disorientation, vision disturbance, hearing changes, involuntary eye movement (nystagmus), and cognitive and/or psychological changes, among others.
Differential DiagnosisVertigo is not the same as dizziness, lightheadedness or unsteadiness. When you're dizzy, you may feel lightheaded or lose your balance. If you feel that the room is spinning, you have vertigo.
For vertigo, differentiate between inner-ear decompression sickness (DCS) and inner-ear barotrauma.
- Vertigo occurring briefly during or after a dive and resolving spontaneously requires evaluation of Eustachian tubes before resuming diving.
- Persistent vertigo is a sign of serious conditions and requires urgent evaluation by an ENT specialist. For an ENT referral in your area, email firstname.lastname@example.org, or call the DAN Medical Information Line at +1-919-684-2948.
- Severe persistent postdive vertigo is an emergency.
Fitness to DiveDamage to vestibular organs by DCS, barotrauma or acoustic shock may be permanent. In case of single-ear injury, vertigo may go away in two to six weeks, because the brain learns to compensate and ignores the side that is damaged, but the canal will not heal. The diver will have difficulties maintaining balance in the dark when deprived of visual clues. Damage to both vestibular organs is debilitating and may make certain life activities (such as driving a car) challenging or impossible.
Persistent or recurrent vertigo, even if controlled by medications, is disqualifying for diving.
Return to diving after inner-ear barotrauma or DCS should be evaluated on an individual basis depending on the extent of permanent injury of inner-ear organs.