Dizziness during dive

[RobC]

I've done a bit of checking and 99% of references to dizziness with diving occurs after the dive is completed (including a check over at the DAN web site).

Can anybody tell me what causes it DURING a dive?

Here's the scenario. I went for my Adventure Deep Dive today. Started out ok. Had to stop at 24 feet and again at 45 feet to equalize my ears (right ear had a very slight pain during one of the pops, but nothing really noteworthy). Hit final depth of 114 feet after a 4 minute (total) descent. Noticed almost immediately that I felt a bit dizzy (meaning everything was spinning around and around). Told instructor straight away and we aborted the dive. He started to take off and from my perspective he was only doing circles around me. Since everything was spinning much faster by now and I couldn't get focus on anything, I didn't trust myself and found a nice rock directly under me to hang onto and stayed put (all the while thrashing my flashlight around to hopefully show distress). This was at 5 minutes in (from the beginning of the dive). He returned about 2 1/2 mins later and helped me to the surface. Took the next 5 minutes to ascend from 114 feet to 15 feet. Did a stop at 15 feet for 4 minutes starting at 13 minutes and ending at 17 minutes.

In all it should have been a relatively good dive. The time taken to go down was ample, the time sitting on the bottom was only 4 minutes, the ascent rate was nice and slow, and did a stop as needed. Overall the full dive from getting in the water to getting out was a grand total of 17 minutes. Yes, I'll have to admit there was a couple bouts of panic (room spinning in complete darkness will do that), but I kept my faculties and didn't shoot to the surface, throw off my mask, kick out the regulator, etc.

So, the question is...what might cause dizziness like that at depth?



(and yes, all times and depths have been verified after uploading the dive computer's memory to my PC)

 

[RobC]

A couple of other bits that I forgot to mention...

About 80% of the dizziness went away once we hit around 50 feet or so. Another 15% went away by the time we stopped at 15 feet.

In general I do not get dizzy nor do I get vertigo. I do not get car sick, motion sick, sea sick, etc. The most I've ever had was only very slight and lasted only a few seconds, but that was while running a 104 fever many years ago.

 

[ParamedicDiver1]

Couple of thought, though I do not know if they are what happened. Could have been a Nitrogen Narcosis of sorts or an inner ear imbalance causing vertigo. I am wondering about the fact that the symptoms resolved after assending to 50ft and then at 15ft. That is what is leaning me towards a nitrogen thing. Will have to do some research and expand on this. Check back later.

 

[Rick Murchison]

Never heard of spinning from narcosis. But spinning is a common (indeed, classic) symptom of alternobaric vertigo. (One ear clearing and the other not - especially on ascent)
Could also be an unequal temperature thing. Were you wearing a hood? any chance one ear stayed relatively dry and the other got cold water in it?
Have you been back down? If so, were you ok or did it happen again?
Rick

 

[jakubson]

Never heard of spinning from narcosis. But spinning is a common (indeed, classic) symptom of alternobaric vertigo. (One ear clearing and the other not - especially on ascent)
Could also be an unequal temperature thing. Were you wearing a hood? any chance one ear stayed relatively dry and the other got cold water in it?
Have you been back down? If so, were you ok or did it happen again?
Rick

I have had it too - probably vertigo. To resolve it, I go back down just a few feet, then ascend very, very slowly. It could have come about by ascending just a couple feet when you were at depth - especially given the fact that you had a slightly difficult time clearing on the way down.

 

[RobC]

Wasn't wearing a hood. And did not go back down since it kinda shot my nerves for the day.

Not sure about the temperature. I only noticed 2 slight thermoclines on the way down. The final temp at the bottom was only 62 degrees.

"it could have come about by ascending just a couple feet when you were at depth" -- trouble is that it happened on the way down. Then cleared up on the way up.

 

[Rick Murchison]

"it could have come about by ascending just a couple feet when you were at depth" -- trouble is that it happened on the way down. Then cleared up on the way up.

It can happen going in either direction, but is more common on ascent. It can be very disorienting, even nauseating.
Based on your symptoms I still think this (alternobaric vertigo) is what you had rather than some form of narcosis.
Rick

 

[JustinW]

Wasn't wearing a hood. And did not go back down since it kinda shot my nerves for the day.

Not sure about the temperature. I only noticed 2 slight thermoclines on the way down. The final temp at the bottom was only 62 degrees.

I am certainly not an expert, but I wonder if the temperature did have something to do with it, being that you were not wearing a hood. Could the cold water have affected you, especially being that it was 62.

 

[RobC]

Dunno. I did a dive not to long ago where I hit 64 feet and it was 61 degrees. Stayed there for some time with no problems.

Right now I'm leaning towards the "alternobaric vertigo" that Rick mentioned. Gonna schedule an appointment with my ENT in any case to see if there are any other screws loose up there.