Unexpected Skin Bends--Why

[guyharrisonphoto]

My doctor's comments were very interesting on this. I do not present this as gospel and Dr. Mitchell and DDM can weigh in.

My doctor feels that what we call "Type 1" skin DCS is a different phenomenon from severe DCS. He views this "skin DCS" as nitrogen off gassing directly to the atmosphere through the surface skin/fatty layer and not by bubble formation. He views "severe" DCS as active bubble formation in the blood, nerves, joints, etc. where the off gassing needs to take place through the respiratory system.

He does not see skin DCS by itself, as a sign of severe DCS, only as an indication to watch for symptoms of severe DCS because the skin DCS has the same underlying cause even if not the same mechanism. Without other symptoms, he said not to be concerned about severe DCS just because type 1 skin bends appear.

He said the vast majority of Type 1 skin DCS cases are never accompanied by symptoms of severe DCS. He also said that the majority of severe DCS cases do not present any skin symptoms at all. That is why he felt there was no direct connection.

I would emphasize that we did not discuss the more serious skin DCS cutis marmorata because I did not have that and it did not come up in our conversation.

 

[Dr Simon Mitchell]

Hello Rob,

I would say that skin bends, particularly the erythematous red "allergic looking" rash, is usually not a sign of severe DCS. Indeed, it most commonly occurs as an isolated symptom. But it is certainly true that skin rashes can be part of a more severe presentation. There is also no doubt that rash as a symptom of DCS is associated with a high probability of the presence of a large PFO, and someone suffering multiple episodes of rash should consider undergoing a PFO test as recommended in the guideline I have uploaded to this post.

Simon M.

 

[Diver0001]

Thank you, Simon.

R..

 

[uncfnp]

Hello Rob,

I would say that skin bends, particularly the erythematous red "allergic looking" rash, is usually not a sign of severe DCS. Indeed, it most commonly occurs as an isolated symptom. But it is certainly true that skin rashes can be part of a more severe presentation. There is also no doubt that rash as a symptom of DCS is associated with a high probability of the presence of a large PFO, and someone suffering multiple episodes of rash should consider undergoing a PFO test as recommended in the guideline I have uploaded to this post.

Simon M.

Thank you for the link Dr Mitchell.

I was somewhat surprised to see migraine with aura listed as a reason for PFO testing since I thought that link had been called into question.

Could you please clarify where you would place lymphatic DCS. Is it in the same risk catagory as minor “allergic looking” skin bends and treated as such? Or does it carry the greater DCS risk progression and associated PFO as cutis marmorata?

 

[KevinNM]

And the abstracts for parts 2 and 3. I wish I had access to the full articles, one must be a subscriber for access.

The Gradient Perfusion Model Part 2: Substantiation of the GPM with clinical cases. - PubMed - NCBI
The Gradient Perfusion Model Part 3: An extraordinary case of decompression sickness. - PubMed - NCBI

A university with a med school will normally have access to all the mainstream medical journals. A university without a med school will probably have at least some. If you go to their library ( usually just anywhere on the university's IP address block will work) you can read them. Sometimes there are ways to get access proxied even to the general public from off-site.

 

[guyharrisonphoto]

I am pleased to report that, after three weeks off, I resumed diving to my regular depths and conditions (90' drift dives). I have made 6 dives and have no symptoms at all of skin bends. I have changed my computer from standard (no) conservatism to the first level of conservatism (+1 out of a range to +5), which shortens my bottom time slightly, and lengthened my safety stops to 5 minutes.

Back in action! Just in time for my California dive trip (first time--always wanted to dive the kelp).

Thanks for all the feedback here.

 

[Duke Dive Medicine]

Awesome! Enjoy the kelp - it's an awesome experience.

Best regards,
DDM