2 embolisms

[Kevrumbo]

A Tale of 2 Embolisms. A friend & I suffered Arterial Gas Embolisms (AGE) almost exactly a year apart, on very similar dives, on the same boat, in almost the exact same location, while we were diving together. Both dives:
1) @185fsw
2) Back gas was air
3) Short bottom times because the anchor was dragging
4) No computer violations
5) Onset of symptoms within 3-4 minutes
6) Paralyzed on 1 side – his left, my right
7) Fully resolved on surface O2 within 30 minutes
8) We both walked up on the dock when we got back
9) Both took a level 1 chamber ride as a precaution
10) Both have resumed diving with no aftereffects
A few differences:
1) My dive had 3-4 minutes bottom time; his was a true bounce dive
2) My ascent was slower due to the amount of scope on the anchor
3) I switched to 50% O2 @ 70fsw even though I didn’t need to as I wasn’t sure I could use the O2 hang reg because of the current. I was able to use it so I had quite a bit safety margin.
Posted for information purposes only. Informed, thoughtful comments are welcome.

This I would assume was a "second" dive? What is the detail of the first dive and what was the surface interval (SI)?

Again, thanks much for actually reading the post.
---------- Post added September 30th, 2015 at 11:29 AM ----------
You are reading it right. Neither of us altered our diving in any way since we made hundreds of dives like this before & after. Probably never know why this happened.

A very critical question by ajduplessis above with regard to the OP that needs clarification: Was the AGE/DCS precipitating dive part of a series of one or more repetitive dives with a Surface Interval, or just a single, stand-alone, one time only dive of the day as implied in the OP above?

There's a "Rule of Thumb Caveat" to never do a reverse profile- deeper Bounce Dive as a second or repetitive dive, because of increased odds of developing AGE/DCS via residual pathological N2 bubbles coming through a venous to arterial shunt such as a PFO or intra-pulmonary anastomoses, and those residual bubbles expanding large enough upon surfacing to cause blood vessel blockage (ischemic stroke).

 

[markmud]

Hi Markm,
I used defect in quotes because, as DDM pointed out, it is not necessarily caused by a birth defect or anatomical defect, it might be caused by excercise post dive or overpressuring your thoracic cavity (breath holding/valsalva manoeuvre) post dive when you have a lot of VGE and alveoly are working at capacity to get rid of the bubbles.
Any perturbation of the pressure balance, speed of the blood stream can allow bubbles to go through the sieve of the lungs and become AGE.

If you want to dive (pun intended) in this you could read a very long thread on CCREXPLORERS.
Simon Mitchell is an hyperbaric doctor and rossh is the author of Vplanner/multideco.
you could start from beginning but is from here where the discussion deepend on VGE/AGE and bubbles #70 Also here #79 and the subsequent post contains a wealth of interesting details.

Cheers

Fabio

Thanks Fabio,

I will "dive" into that thread.

markm

---------- Post added September 30th, 2015 at 03:06 PM ----------

Anyone can shunt bubbles through the pulmonary circulation, it's not necessarily related to a defect. That's one of the reasons why vigorous exercise after diving is discouraged.

Best regards,
DDM

Thanks DDM,

I am slowly getting a better handle on this (for a lay person anyway).

---------- Post added September 30th, 2015 at 03:15 PM ----------

Mobile Diver wrote:

"Couple of other points:
1) My research says 3-4 minute onset + 1 side paralysis = AGE by far the most likely cause.
2) Since some asked - my computer uses Buhlmann ZLH16 algorithm. Not that it makes any difference."

Hi Mobil Diver,

I am glad to know that you seem to have no long term issues from your incident. I am not a tech diver so I didn't understand some of the nuances that you had in your OP. Sorry about that.

Question: Did the Chamber Tech or physician give a diagnosis for your condition?

Thanks for starting this thread as I have enjoyed it.

markm

---------- Post added September 30th, 2015 at 04:43 PM ----------

Hello Again Fabio,

I read the linked thread you posted above well beyond the posts that you cited on this thread. That was worthwhile!

I had to read from the OP to get the full context.

...those 4 forms of DCS known to be associated with venous to arterial shunting of bubbles could occur through that mechanism in a person without a PFO (or a person with a repaired PFO). (Simon Mitchell)

Another poster described an incident where he held his breath, on deck, and lifted something heavy, and may a have caused an DCS (AGE or VGE?) that manifested itself in his eyes (blurred vision and symptoms similar to a migraine headache).

Very interesting.

Thanks again!

markm

 

[Mobile Diver]

---------- Post added September 30th, 2015 at 03:06 PM ----------





Mobile Diver wrote:

"Couple of other points:
1) My research says 3-4 minute onset + 1 side paralysis = AGE by far the most likely cause.
2) Since some asked - my computer uses Buhlmann ZLH16 algorithm. Not that it makes any difference."

Hi Mobil Diver,

I am glad to know that you seem to have no long term issues from your incident. I am not a tech diver so I didn't understand some of the nuances that you had in your OP. Sorry about that.

Question: Did the Chamber Tech or physician give a diagnosis for your condition?

Thanks for starting this thread as I have enjoyed it.

markm

---------- Post added September 30th, 2015 at 04:43 PM ----------

Doc said most likely AGE. They did not give my friend a diagnosis as I recall.

 

[CAVEDIVERCHICK]

How can symptoms of an AGE be fixed by breathing 100% on the surface within 30 minutes? Also, isn't paralysis a symptom of DCS? Just curious.

 

[markmud]

How can symptoms of an AGE be fixed by breathing 100% on the surface within 30 minutes? Also, isn't paralysis a symptom of DCS? Just curious.

Hi Cavediverchick,

I am not the go-to person for answers, but I did find this at DAN:

"On the other hand, air embolism may cause less spectacular symptoms of neurological dysfunction, such as sensations of tingling or numbness, a sensation of weakness without obvious paralysis, or complaints of difficulty in thinking without obvious confusion in individuals who are awake and easily aroused. In these cases, there is time for a more thorough evaluation by a diving medical specialist to rule out other causes of symptoms. Like DCS, mild symptoms may be ascribed to causes other than the dive, which only delays treatment. Sometimes symptoms may resolve spontaneously and the diver will not seek treatment. The consequences of this are similar to untreated DCS: residual damage to the brain may occur, making it more likely there will be residual symptoms after a future bout of AGE, even if the later bout is treated. "

Decompression Illness: What Is It and What Is The Treatment?

I hope I understood your question.

markm

 

[Mobile Diver]

How can symptoms of an AGE be fixed by breathing 100% on the surface within 30 minutes? Also, isn't paralysis a symptom of DCS? Just curious.

Oxygen shrinks bubbles. Sometimes quickly. The entire side paralysis is & quick onset indicates AGE. DCS is usually slower onset.