DCS in Cozumel

[uncfnp]

To the op, if you are still listening...

1) Not all DCS is created equal. I assume since you took a ride that the hit was fairly serious although I know some chambers will elect to treat if there is any doubt.

2) You have had multiple recommendations in part because much of decompression theory is just that...theory. Assuming that the PFO is there and you do elect to dive without closure, reducing your bubble load is manditory.

3) FWIW this is my approach...

First and foremost I recommend buying a “conservative dive computer” and or use CF/SF if that is an option (i would love to know the computer you were using with the dive that lead to your hit.) on your current computer Conservative diving is a multifactorial procedure, bottom time, depth, sawtooth dives, safety stops, surface intervals, nitrox percentage, ascent rates...A conservative computer will help you moniter and manage all these factors and more specifically, a computer that factors all this into the algorithm.

Dive the highest level nitrox safe for your dives. Since you will be limiting your profiles 36 will likely be a good option but otherwise 36/32 that is widely used in Cozumel.

And it may seem extreme but consider getting Advanced Nitrox certified. This will give you access to ligher levels of nitrox and teach you how to manage the risk/benefits of pushing MODs and possibly better access to O2 on the surface.

Not knowing more specifics its hard to suggest any other more concrete actions. If you are willing to share more about the event and your dive experience, future dive plans, we might be able to suggest more concrete steps to decrease your risk.

 

[Dave Dillehay]

The easiest way on the first dive will be to hire your own DM. It usually runs about $50 a day and while you will ride out with a larger group, you and the DM will dive your own dive to you specifications. This option will work great for the first dive, but extending the surface interval would be an issue here. maybe if an op was doing an afternoon dive, you could cab back to town on the SI then catch the boat again for the afternoon dive. I have seen people just dive the morning dive with Aldora and catch a cab back from the beach club on the SI.

Depending on how many people you usually dive with, chartering your own boat is another option. We did that on our first trip years ago and it was right at $400. At that point, it's your boat and you do what you want...within reason. With a group of 4, it becomes reasonable.

I know there are some "independent" DM's on the island that are basically a DM, a captain, and a boat. It might be cheaper to charter one of those boats, but I don't know of any to contact.

I'm curious if there has been a diagnosis that makes you particularly susceptible to DCS, PFO maybe? Also, would breathing O2 on your surface interval reduce the time necessary?

Good luck,
Jay

AT Aldora Divers we can always provide an 80-60 ft first dive followed by 45 -50ft , with a long 2 hour surface interval. That is guaranteed if that is your need. Out of our 9 boats we use that as the "beginner" boat. Normally Palancar Gardens first dive then Paso De Cedral, or any such mix.

Dave Dillehay

 

[mstevens]

PFO (of any size) is significant if right atrial pressures exceed the left, resulting in brief right to left shunt.
You didn't describe your symptoms, but since exertion is very highly correlated with microbubbles, and you note "sneezing three times", you have described exactly the sort of setup for a brief right to left shunt of existing bubbles.

There are catheter methods of closing small PFOs that are not as invasive. If you want to still dive and you have had two DCS hits, it's pretty straightforward - you should close your PFO.
Changing SI or nitrogen loading will only decrease, not eliminate your microbubble formation, especially with exertion.

I would suggest you need to eliminate your demonstrated occurrence of R to L shunt.

All the above based on grossly inadequate data and some speculation.

Diving Doc

Yeah, but how would medical school, residency, and perhaps a fellowship possibly make you more qualified to comment on this than some anonymous guy on the internet with access to Google and strong opinions?

 

[leadduck]

I was diagnosed on this trip with what was described as a "very small" PFO, although why it became a problem after nearly 25 years of diving is a puzzle. Clinic in Cozumel said it was too small to make surgery an option. The deepest dive this trip was about 80 feet, I've spoken with the divemasters and no one can figure out what happened. We ran into a really strong and unexpected "headwind" current on one dive, and I sneezed several times on another (how weird is that?), but there was no really obvious cause.

Some 25% of people have a small PFO like you. If that alone would cause DCS then we'd see a lot more DCS but we don't. The PFO opens under strain, for example sneezing, Valsalva maneuver, bowel movement, cough, climbing into boats, lifting heavy stuff. Better avoid all of that and take a good rest during peak bubbling 30-60min post dive. Please see https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3710076

Maybe you have an other risk factor besides PFO? Obesity, age, poor physical condition, chronic lung disease?

 

[Lorenzoid]

The OP said, "Clinic in Cozumel said it was too small to make surgery an option," apparently accepting the clinic doc's opinion as the end of the story (although he did say he consulted at least one other doc and DAN). I suggested he get a second opinion on the feasibility of closing the PFO. He replied, "I'll pass on the surgery, thank you." I interpret that as the OP not showing interest in advice even from the doctors here. Kudos for trying.

 

[leadduck]

I guess closing the PFO is feasible for him but the procedure is not without risks. The paper I cited above cites Edmond's Diving Medicine saying that repair of the hole is probably more dangerous than diving with it. Therefore living with the PFO while avoiding DCS by more conservative diving may be well preferable even if he can easily find a doctor who'd close it.

 

[rsingler]

I would respectfully disagree.
After two hits, the risk scales may have tilted for this diver.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3710076
This is an excellent UK review article, which should be read in its entirety to gain context. But some facts should be taken with a grain of salt when considering the US experience. For example, during catheter closure, a nearly 1% incidence of the device breaking off and traveling elsewhere in the circulation seems extraordinarily high, as does the quoted incidence of a tear in a blood vessel requiring subsequent surgery.

I'm jes sayin'

Diving Doc

 

[uncfnp]

For the OP. Look most closely to the posts by DDM and Dr Ebersole...

2 DCS hits and a PFO closure

Update on PFO Study

Diving with mitral regurgitation and a small PFO?

And this...

Alert Diver | Patent Foramen Ovale and Fitness to Dive

 

[rsingler]

From @uncfnp 's excellent list of links, the
2015 PFO and Fitness To Dive Consensus

https://www.diversalertnetwork.org/...Proceedings/2015-pfo-workshop-proceedings.pdf

 

[Dr. Doug Ebersole]

I'm sorry but I have to say something. As far as my experience goes, I've been diving for well over 40 years, I teach diving through CCR full trimix, and I am an interventional cardiologist who is a cardiology consultant to Divers Alert Network and close PFOs for divers as well as for patient's with cryptogenic stroke on a regular basis.

First and foremost, I would like to thank the OP for presenting his situation as we can all learn from these events. And please continue to post on Scubaboard as it is a great resource for the diving community.

Secondly, please take all posts here (including mine) with a grain of salt. These are opinions from people who don't know you, don't know your situation, have a wide variability of dive experience and/or medical knowledge. I tell my patients all the time to please not get their medical advice from the internet.

Here is my best advice from the information you have given us. It sounds as though you have suffered two episodes of unexpected DCS though either you didn't say or I missed what your actual symptoms were. PFO is a normal variant in the general population and occurs in about 25% of people. It is not a "disease". It does,however, increase your risk of specific types of decompression sickness by about 5 fold -- specifically CNS bends (stroke-like symptoms), Spinal (paralysis, bladder issues), Inner Ear (vertigo), and skin bends (a classic marbled rash). While a 5 fold increase sounds bad, the ABSOLUTE risk of DCS with a PFO is still quite small, increasing from 2 per 10,000 recreational dives in the general popluation to about 10 per 10,000 dives (or 1 in a thousand) for divers with PFO. For this reason, we do not screen divers for PFO and we don't close them if one is found incidentally.

Also, as 25% of the general population has a PFO, you would expect 25% of DCS patients to have PFO and the two may not be related at all. However, if patients have recurrent episodes of unexpected DCS of the types I mentioned above, the PFO "may" be a contributing factor. However, the culprit is the inert gas load, not the PFO. Anything a diver does that can decrease the inert gas load will lower his/her risk of recurrent DCS.

The options for the OP are three fold in my opinon:
1. He can stop diving -- which he has plainly stated he is not going to do
2. Dive "conservatively". This is usually defined as diving nitrox on air profiles, diving less than 100 fsw, diving no more than twice per day, and doing longer safety stops and long surface intervals. Anything a diver does even more conservative than this can only make him or her even safer.
3. Closing the PFO. This is an option for divers with recurrent unexpected DCS that have been diving as "conservatively" as they can for the type of diving they enjoy. This is in the "eye of the beholder". I have closed lots of recreational divers but also technical divers that only enjoy deep, decompression diving and are not willing to go back to only shallow and short dives. It's all a personal decision being aware of the risks and benefits of the procedure.

PFO closure is a very safe outpatient procedure. Patients come in to the hospital in the morning and it is a less than one hour procedure under conscious sedation (intravenous "twilight" meds like having an endoscopy). They then go home in the afternoon. It is all done through a needle stick in the groin similar to a heart cath but in the vein and not the artery so bleeding issues are less common. The success rate is well over 98% (nothing is 100%) and the complication rate in good hands should be about 1% or so. This is usually bleeding or some palpitations for a couple of weeks after the procedure that resolves on its own. The likelihood of the device embolization, for PFO closure, not for ASD closure, should be 0% though I guess anything can happen.

There is not a PFO that is "too small" for closure. These defects are "flaps" and not "holes" and can vary in "size" depending on loading conditions, volume status, etc.

Just my 2 cents

Oh, and the idea that you have an "existing condition" that should disqualify you from diving, in my opinion, is ridiculous. And I am saying this as a physician, a dive instructor, and a dive shop owner. If you enjoy diving, please continue to do so -- and on the usual charters, not only on private boats with private guides, etc. Just dive as safely as you can. Either be as conservative with your diving as you can be and still enjoy our sport or see someone who actually closes PFOs for a living and have them review your echo results, speak with you in detail, examine you, etc and not make significant lifestyle changes based on the opinions of people on the internet who have never met you -- and that includes me.

Douglas Ebersole, MD
Interventional Cardiology, Watson Clinic LLP
Cardiology Consultant, Divers Alert Network