Patent foramen ovale

[Snowbear]

...dismissed AGE as the cause because
I did not suffer from pulmonary baraotrauma. (It is quite possible that I did and it was missed!)

With an underlying PFO, AGE would be possible without accompanying Pulmonary Barotrauma, would it not?

 

[The Iceni]

With an underlying PFO, AGE would be possible without accompanying Pulmonary Barotrauma, would it not?

Hi Snowbear,

My point exactly. I think is is just too easy to believe that the only cause of AGE is Pulmonary Barotrauma.

This article by scubadoc is quite enlightening.

And this is the gadjet I am now walking around with inside my ticker!

 

[reubencahn]

I'm sure this is covered elsewhere, but could someone explain exactly what is done to test for PFO and are different tests necessary to detect less severe cases?

 

[The Iceni]

If you sign on to this service reuben, you will get a full explanation!

TEE - transesophageal echo cardiogram.

 

[detroit diver]

I'm sure this is covered elsewhere, but could someone explain exactly what is done to test for PFO and are different tests necessary to detect less severe cases?

My first test was an echogram with bubble study. Basically, they inject small amounts of small bubbles into your blood system while monitoring you on a chest "ultrasound" machine. They make you cough and can see whether the bubbles pass thru.

In my case, there were a few bubbles. My cardio guy suggested the TEE, and although the thought of it didn't thrill me, I'm glad I went thru with it. It gave the surgeon a preliminary look at what he can expect to deal with.

 

[Snowbear]

this is the gadjet I am now walking around with inside my ticker!

I've seen scubadoc's article before, as well as much more detailed ones. What I haven't done much reading on is repairs.

That gadget's pretty slick! From looking at the web site, it looks like those are primarily used for severe cases - or are they just using the worst case scenarios for advertising? I see it's removeable - you say you have one of these in place, yet in another post your PFO is not yet fixed. Does this mean this is not considered a permanent repair? Does it seal the hole or just minimize leakage?

Does a permanent fix involve open heart surgery, or can it be done via a cardiac cath type procedure?

If I'm getting too nosy, please tell me - though my medical training is minimal compared to yours, this stuff is interesting to me so I'll keep asking questions as I think of them unless you ask me not to :54:

 

[detroit diver]

I've seen scubadoc's article before, as well as much more detailed ones. What I haven't done much reading on is repairs.

That gadget's pretty slick! From looking at the web site, it looks like those are primarily used for severe cases - or are they just using the worst case scenarios for advertising? I see it's removeable - you say you have one of these in place, yet in another post your PFO is not yet fixed. Does this mean this is not considered a permanent repair? Does it seal the hole or just minimize leakage?

Does a permanent fix involve open heart surgery, or can it be done via a cardiac cath type procedure?

If I'm getting too nosy, please tell me - though my medical training is minimal compared to yours, this stuff is interesting to me so I'll keep asking questions as I think of them unless you ask me not to :54:

I don't want to speak for the Doc, but the unit is NOT removeable after it's been in place for a while. It gets covered with skin growth. It's only removeable during the procedure if the fit is not correct (or something else goes wrong).

As was explained to me, sometimes the device does not completely cover the hole (PFO) at first because of the way it is shaped and the shape of the hole. It will, however, close over time with the skin growth that is happening nearby. I asked how long after the procedure that I could resume diving. I was told that given a perfect fit-about a week or so. With a non-perfect fit it could be 3-5 months.

 

[Snowbear]

I don't want to speak for the Doc, but the unit is NOT removeable after it's been in place for a while. It gets covered with skin growth. It's only removeable during the procedure if the fit is not correct (or something else goes wrong).

So this is done via cardiac cath? Medical technology is amazing to me. A week! That's incredible! Hopefully yours is a good fit

 

[fins wake]

I think it was Sherlock Holmes who said something like "If you exclude the impossible the answer can only be what is possible." (No doubt someone will correct me).

When you have eliminated all which is impossible, then whatever remains, however improbable, must be the truth. (From "The Blanched Soldier"). More famous is the statement, "How often have I said to you that when you have eliminated the impossible, whatever remains, however improbable, must be the truth?" (from "The Sign of [the] Four").

Now I do not believe in miracles. My intact survival was, I believe, entirely due to the fact that I was breathing Nitrox (so had a marginally elevated oxygen reserve), hypothermia and immediate effective BLS - I was ventilated with 100% oxygen on scene by an ex-army medic.

In turn, yes (to miracles), no (as no amount of nitrox will give an oxygen reserve to keep an adult male alive without breathable gas supply for 14 minutes even in ice cold water), yes (to hypothermia) and yes (to immediate BLS).

Now as to the cause. I discussed this with a recognised UK diving doctor expert who, like fins awake, completely dismissed AGE as the cause because I did not suffer from pulmonary baraotrauma. (It is quite possible that I did and it was missed!)

(a) Glad I have some backing here, and (b), it wouldn't be missed.

Perhaps I should list the possible causes of the incident? My buddy described me a losing consciousness and then I appeared to fit. 1) equipment failure - No

Fair enough.

2) out of gas - No (the rescuers found me from my bubbles)

A very important point which not only makes the 'oxygen reserve' unimportant, but which may hint at a possible cause. Think 'grasping on to your reg' despite being AWOL. E.g. the tragic Norwood fatality.

3) C02 retention - on OC?

Entirely possible, but no more a given than anything else. Incidentally, CO2 retention is often more notable on OC than on an RB ... (hint: the scrubber).

4) CO or other gas poisoning - same set as on first dive so no

Depends. 48 min RT on a first dive is more than what is usually required for CO poisoning on the second. However, I'd like to have a look at the contents of the deco gas bottle as well ...

4) CNS oxygen toxicity - my ppO2 at 21M (EAN32) was 1 bar - possible I admit but is is as likely?

Agree, very unlikely.

5) AGE - from PFO or PB is possible and would produce the effects witnessed.

Possible in extremis, but for all other purposes would still require something beyond normal protocol IMHO to produce the (C)AGE. For example a breath-hold ...

Now. Does this mean I think every diver recruit should be screened and treated for a PFO? Not at all. I had been diving for over 30 years - on and off -without incident. The difference on this occassion was that it was the second of two shore dives and I had carrried very heavy kit on the cliff ascent immediately following the first dive. I provoked it!!!

An interesting thought, but I'm still to be convinced.

The other clue is that I have a history of cluster migraines.

Ah, but this doesn't necessarily point to an AGE ...

(As an aside DCI was not even considered in the differential diagnoses. If I am right I would have recovered much quicker if I had been recompressed.)

This is actually the reason I don't believe it was an AGE at all. An AGE would definitely have been affected by recompression, and inversely, without hyperbaric oxygen, you probably wouldn't have survived at all ... So personally, I'd rule any form of DCI out at all ...

If pushed, I'd look into points (3) and (4)(i), CO2 or CO or other gas poisoning. Alternatively, a breath-hold and ensuing AGE (but without the recompression, I really doubt the cure and hence this diagnosis). Finally, simply user error, i.e. breathing from the deco bottle during a rushed 'emergency training' ascent, and hence true oxtox. But in the end, I still think a final conclusion is very hard to reach. With all due respect, I'm merely exercising - or trying to exorcise - those literary brought-up-on-Spilsbury-Sydney-Smith-and-Keith-Simpson genes.

Fins
(BTW I always thought Fitz was wrong about Cassidy at the end of "One Day A Lemming Will Fly". Of course Cassidy was guilty! :54: )

 

[detroit diver]

"Originally Posted by The Iceni
The other clue is that I have a history of cluster migraines."

"Ah, but this doesn't necessarily point to an AGE ..."


But it does point to a potential PFO. Studies show a marked improvement in migraines after PFO repair.