Inner Ear Decompression Sickness on recreational dive

[DandyDon]

My concern with having the test for PFO is that if found, I can no longer dive.

I am curious where you got that idea?

BUT... approx 30% of people have a PFO, which I guess would mean approx 30% of divers are diving with one. The rate of DCS is much much lower than that so the odds are that I could continue diving and probably not ever have an issue again. It's really hard to decide whether to take the risk or not.

As far as a PFO is concerned, it's not a disqualifying condition. There could be other issues?

Here is an interesting excerpt from Dr.Bove in comparing opinions in this article: Alert Diver | PFO and Decompression Illness in Recreational Divers

I would not recommend PFO closure in any sport diver, whether or not the diver had a DCS incident. The noted incidence of DCS in recreational divers is between two and five cases per 10,000 dives (0.02 percent to 0.05 percent). The serious complication rate for PFO closure, as noted in Dr. Douglas Ebersole's comments, is 3-4 percent, more than 100 times the risk of experiencing a DCS event. It is clear that the risk-benefit ratio for PFO closure in divers strongly favors not closing the PFO. Further, the presence of a residual PFO after closure is significant, up to 30 percent in some studies.

 

[clownfishsydney]

I had a somewhat similar thing happen in Chuuk. A short time after a dive (the 5th of the trip), I became dizzy and ill. I could not walk and vomited any time I opened my eyes. I was given 5 treatments in the chamber, but I never felt better at depth or after the treatment (apart from what would be expected after 5 hours had passed). Therefore, I do not think it was a bend.

As to PFO, I know a number of divers here who have had repaired without any complications and continue to dive.

 

[duke dive medicine]

I am a bit confused with whether to investigate a PFO or not. My Hyperbaric doctors did not feel it was necessary as the decompression sickness was "deserved" (multiple dives on consecutive days). However, my local dive doctor has concerns, especially as I also suffer from Aura Migraines and unexplained mild Sleep Apnoea (I am very active, fit and of good weight) She feels I should be tested.

My concern with having the test for PFO is that if found, I can no longer dive. BUT... approx 30% of people have a PFO, which I guess would mean approx 30% of divers are diving with one. The rate of DCS is much much lower than that so the odds are that I could continue diving and probably not ever have an issue again. It's really hard to decide whether to take the risk or not.

Thanks so much for your advise. I am missing diving so much, but I won't be returning to it at least until my dizziness is resolved.

Cheers, Kathryn

Hi Kathryn,

That's a tough position to be in - two diving medical groups have examined you and have opposite opinions.

I wasn't there, didn't examine or treat you, and am basing my opinion only on what you've posted, but I am in agreement with your hometown diving physician. You did have a pretty aggressive dive profile, so in that sense your DCS may be explainable. If you'd had joint pain and numbness that began an hour after surfacing, I wouldn't even think about PFO testing. However, the index of suspicion for PFO is higher in you due to the location of your symptoms and the fact that they occurred so quickly.

Your observation about the odds of having a PFO vs the odds of DCS is a good one. There's also the ironic twist that PFO is usually only discovered in divers after they've had an incident like yours. Still, the conservative approach is to stop diving, and that's the advice we usually give divers in this situation. We then add the caveat that if they choose to continue diving, they should do so very conservatively in order to minimize venous bubbling: use nitrox, preferably on air tables or with an air computer; don't push the computer to the edge of the algorithm; and when on a dive holiday like yours, take a break in the middle and don't dive for a day. Also, give yourself a day to off-gas before you fly out. A study by Marroni and colleagues, cited in Mark Powell's excellent book Deco for Divers, found that making a short stop at 15 meters in addition to a 6-meter safety stop significantly reduced detectable venous bubbles. It can be found here:

[abstract] USE OF A DEEP (15M) AND SHALLOW (6M) STOP FOLLOWING 25 METER NO-DECOMPRESSION DIVES REDUCES DECOMPRESSION STRESS (AS OBSERVED BY DOPPLER-DETECTABLE BUBBLES) WHEN COMPARED TO EITHER A DIRECT ASCENT, OR DIRECT ASCENT WITH ONLY A SHALLOW STOP

Your concern about your other incidents of dizziness after diving is well founded. It could be as simple as alternobaric vertigo from your ears not equalizing completely on ascent, or it could be an indicator of a more serious problem. PFO is sometimes lumped into the category of disorders called atrial septal defects, or ASD. An ASD that is not a PFO is an absolute contraindication to diving, because ASDs are typically larger and more prone to shunting. If this is what you have, your are placing your health in jeopardy by diving. This is another reason to consider having a bubble contrast echocardiogram.

I hope this helps, and please keep us posted on your progress.

Best regards,
DDM

 

[koyote1111]

Hi Kathryn,

I'm so very sorry to hear about your situation...and I do wish you all the best in terms of a full recovery (much sooner than later!). I experienced a Type II "hit" in June '11 while diving in Cozumel. I was within all RDL's and doing two dives a day. I now realize that I was having my first symptoms at the end of day 3...yet on day 5, I was very "bent".

Because my case was catergorized as "unexplained" (no obvious reason for the incident), I was referred to a dive physician. He did suggest that I be checked for a PFO. I indeed tested positive for the PFO (and also ASD).

I did not want to be tested as I was a bit afraid to actually know. However, I'm now very glad that I did so. Two months ago, I had a closure surgery performed and since that time, I have noticed some improvements in my overall health. I have not had a headache since the surgery (which is somewhat of a miracle).

I was released to begin exercising one month ago. What I'm finding is that I do not experience as much post exercise fatigue. By the way, I was always extremely fatigued after diving.

At this point, I think that I was very lucky in that I'd done 130 dives prior to taking the "hit". The doctor's said that the size of my hole was "significant". I was also pretty heartbroken in that I'd just completed my divemaster cert. the week prior to getting bent.

At month 3 (post surgery), I will have another echo to determine if the surgery was a complete success. If so, I will be released to return to diving.

So...just wanting to reassure you that regardless of the results, it can be helpful to know if you may have a PFO or ASD. It will not end your diving adventures! It's also possible that it could guide you to better health in general.

Some interesting things that I learned along the way.....
~ the PFO tends to get larger with age
~ it is possible that this can increase your risk of stroke
~ it is associated with Migraines with aura, being short of breath, and post exercise fatigue
........and

~ the military does not allow it's service members to dive if they have a PFO! In fact, they are first tested.

I do realize that the "jury is still out" on this issue...yet I chose to have the problem resolved. There is a reference above quoting Dr. Ebersole. Interestingly though, he performs PFO closures for divers.

Hang in there...best wishes to you,

Bev.

 

[CaveMD]

I wish you the best, I know quite a few in the technical crowd that had to have a pfo closure after taking a hit from a fairly benign dive profile.

 

[aquaregia]

One of my buddies asked me underwater if I enjoyed the dive and I flipped her off. Not normal behavior. I surfaced with the rest of my team after a long safety stop (10 minutes or so) and started cursing and spitting and generally being a butthead.

Sadly, those of us who are always buttheads don't get the opportunity for this diagnostic step

 

[farsidefan1]

Coz must be the place for DCS. I had the good fortune of having Dr. Piccolo waiting for me and I was in the chamber within a half an hour. I was checked for a pfo (and found to have one) which I had repaired. It is minor surgery (if anything involving you heart is minor) where they go up through your thigh. It was an outpatient procedure. I was told no diving for 6 months. Since then lots of repetitive dives and no issues.

 

[Kathryn_Rob]

I am finding the whole topic of PFO a very confusing one...

My dive doctor thinks it is likely that it will be found that I have one. But do I want to know?

Although recommending I have the test, she is also heeding caution that if found I will no longer be able to dive and it will NOT be recommended that I have a closure. I know this is the safe option, but I'm devastated at the thought of never diving again. BUT I have also been told that if I have a PFO it does not necessarily mean I will experience DCS again. I will be at higher risk but I also could do many more dives with no incident. So maybe I will be ok if I ignore it and do all future dives conservatively...

I spoke with DAN who told me I would still be able to dive if a PFO was found provided that I only dived within the restrictions they agreed safe for me (depth, number of dives and minimum surface interval). Something positive! He urged me to have the test for PFO done as I have had such a significant decompression event with unexplained cause. He warned that the blurred vision I had mean't that I had a bubble in my brain affecting my optic nerve which could have been very bad. After we spoke I was convinced I needed to have the PFO investigated, HOWEVER my local doctor then warned me that if a PFO is found no dive doctor would pass me fit to dive, which would mean I would not be able to provide DAN with a fitness to dive certificate - therefore back to square one - I'm not allowed to dive.

My dive doctor has told me that there are risks involved closing a PFO and it would not normally be considered for any reason other than diving. I couldn't justify having heart surgery if it was JUST to continue with my dive hobby. However, I also suffer from Aura Migraine's and struggle with excessive fatigue, and I believe you are at increased risk of stroke if you have a PFO. If it resolved those other symptoms then it would seem worth considering a closure. So why would a cardiologist only consider a closure for diving? Is it because 20-30% of the population have one and they would be doing too many procedures? Why do you have to wait until you have had a stroke to have closure considered?

There seems to be a lot of uncertainty over the issue, and I'm swinging back and forth trying to decide whether to have an investigation or not. I am unable to dive at the moment due to my residual inner ear symptoms so I guess I have time to work this out. A big thank you to everyone that has taken the time to offer feedback to me. I appreciate it so much.

Kath

 

[duke dive medicine]

Kathryn,

I've emailed a colleague in Australia to try to get some insight into the policy on clearance to dive for people in your situation. Will get back to you.

Best regards,
DDM

 

[Kathryn_Rob]

You are amazing. Thank you so much for your support!