Head Rush at 25 - 20 ft!?

[raviepoo]

Last March I felt a distinct head rush breathing air at 98 feet. I ascended a few feet and the feeling dissapated. I assumed it was due to nitrogen narcosis.

Last weekend I felt the same sensationas I was ascending and getting into position for a safety stop. It passed after a moment. I'm pretty sure I wasn't narked, because I was no deeper than 20 ft.

Does anyone know what could cause this? The sensation was not unlike the aftermath of drinking several shots of tequilla, all at once, very quickly. I was kind of freaked out.

 

[chrispete]

Sounds like a reverse block - it would cause dizziness and possibly nausea. I'm sure the docs can do much better on the details.

 

[Spectre]

Were you in cold water? Wearing a hood?

If that's the case, rather than paraphrasing what the good Medical Regulators have to say, check out these two threads and see if it seems to fit:

Dizziness and vertigo

Vertigo...nausea...again..why?

 

[raviepoo]

Originally posted by Spectre
Were you in cold water? Wearing a hood?

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Yes I was in cold water, wearing a hood. I had ascended from a bottom temperature of 45 degrees to near the surface where the temperature was in the 70's. I did a very carefull, slow ascent, so speed was not a factor.

I read the two threads you directed me to. Maybe I had an episode of vertigo? If so, my next questions is - does this mean I am "prone" to vertigo and should reconsider whether I want to be diving? A "yes" answer to that question would be more than I can handle. In 100 dives I have experienced this sensation twice, and I'm not yet ready to give up on the idea that the first instance had something to do with nitrogen.

 

[Spectre]

Originally posted by raviepoo
I read the two threads you directed me to. Maybe I had an episode of vertigo

I was thinking more a case of having cold water in one ear and not the other as you came through the thermocline, causing your head to spin.

I read those threads, and I didn't read that vertigo was a 'retirement' type of problem... We'll have to wait until the Med-Regs show up!

 

[DocVikingo]

Hi raviepoo,

Not sure what you mean by a "head rush." Did you experience dizziness, lightheadedness, spinning, giddiness, anxiety, upset stomach, disorientation, other symptoms?

Also, Spectre mentioned the possibility of cold water in one ear & provided a thread from our archives. While I'm not yet convinced that this is what caused your event, if you wish read about it the following gives a more detailed coverage of the topic---> http://www.scubaboard.com/showthread.php?s=&threadid=10685&highlight=alternothermic

Best regards.

DocVikingo

 

[raviepoo]

How can I describe this?

Dizzy and lightheaded, I suppose, kind of the way I felt when I sniffed amyl nitrate in my mis-spent youth. No nausea or spinning. I felt a bit of anxiety after it passed as I looked back and asked myself, "what the heck was THAT?!?"

It wasn't a painful or unpleasant sensation, but it was clear that for a second or two I was not fully in command of my wits. Under water I want to be in command at all times. It was as if all awareness of my physical self briefly contracted to my head. I don't know how else to describe it.

Originally posted by DocVikingo
Hi raviepoo,

Not sure what you mean by a "head rush." Did you experience dizziness, lightheadedness, spinning, giddiness, anxiety, upset stomach, disorientation, other symptoms?

DocVikingo

 

[tchil01]

I've had similar experiance several times. Not on every dive but probably 4 or five times. Mostly in cold water or when there has been a significant thermocline. Based on what I've read here I've written it off as Vertigo and not worried about it. It never last more then a minute or so and having experianced it more then once I don't get worried when it happens.

Ty

 

[Laurence Stein DDS]

Ravipoo,

I'm gonna make two educated guesses as to the cause of your problem. The first on my list is alterbaric vertigo. This is caused by unequal pressures withing the middle ears. It can happen going up or down but usually it is noticed on ascent in the last 20 or so feet. You actively pressurize your ears on descent but generally, you passively allow them to "equalize" on ascent. The symptoms are lightheadedness, vertigo, nausea and possibly fullness in the ear or ears.

If you avoided the nausea, then it may have seemed like a "rush". The following article is by Fred Bove, MD, PhD

http://www.skin-diver.com/departments/ScubaMed/Vertigo.asp?theID=338


Caloric stimulation can also result in vertigo. Water of unequal temperatures--especially if cold can cause this. As the temperature equalizes it goes away. Try this link.

http://www.nlm.nih.gov/medlineplus/ency/article/003429.htm

Because your symptoms occurred at a shallow depth and at the end of a dive, my money is on the alterbaric vertigo. What do I know though...just a dentist! Let's get DocVikingo back--he'll know for sure.

Regards

Laurence Stein DDS

 

[chrispete]

In my reply above, I mentioned a revese block as being a possible cause - when a block and subsequent release of pressure happens in the eustachian tubes (the alterbaric condition the Dr. Stein mentions above), is it still called a reverse block, or is there another "common" term that is used? Just want to make sure I have my terminology correct...