Neurological Bends

[gazza]

Hello Doctor,

I was unfortunate enough to have a shallow onset type-II bend earlier this year after a 12mtr 60min dive. The symptoms were an altered sensation/ pins & needles in my forearm about a day after the dive.

After recompression treatement, i was cleared to dive after a 4 week layoff. Since then i did 3 dives to 12,12 and 8mtrs for about 60mins, all on EAN40, with no ill effects.

However, the next dive i did, 4 days later, 11mtr for 60min on EAN40, resulted in another type-II bend in my forearm/wrist and hand.

After these 2 episodes in the space of 3 months, i was not desperate to get back into the water, something that the diving doctor agreed with, suggesting that it would be a good to look for another hobby.

Obviously, now the dust has settled, i'm wondering if this was completely the right decision to take, especially after reading articles like 'me & my pfo'. I wouldn't want to not dive if i could, in the same way that i wouldn't want to dive if it were going to lead to worse dci incidents.

Thanks.

 

[Kaos]

This is just my opinion, but I would think your bad luck would be due to something specific, I have never heard of anybody getting bent (in my surroundings anyway) after diving to such shallow depths. Hopefully it's something like PFO that can be possibly fixed so you can get back in the water again.

Best of luck!!

 

[Frank O]

Hi Gazza,

Early in my diving career I had a fairly similar experience (pins and needles and other sensations in hand/wrist/forearm) that occurred about 16 hours after a dive that normally would not be expected to pose any bends risk. After consulting with DAN I was treated in a chamber, which the on-site physician felt was a successful response to a mild case of DCS.

The symptoms later recurred, however, and based on the pattern of how they recurred my hyperbaric doc back at home concluded that I had never been bent at all. Rather, after conducting a variety of tests (for example, a negative PFO test) he came to believe that, in my late 40s, I have some degree of arthritis in my spine which can result in compression to the nerve (the ulnar) that runs down my left arm to the lower fingers. After some experimentation I determined that during dives I tend to bend back my neck in a way that brings these symptoms out. I've now characterized it to the degree that I'm confident that I can distinguish these symptoms from a real case of the bends.

There's a lot you don't say in your post (how much diving history you had successfully before these experiences; any other extenuating factors such as dehydration or post-dive exertion). But just as a thought you might press your docs to rule out other possible causes.

Needless to say I'm just another rec diver sharing my personal experience, and have no qualifications whatsoever to give you medical advice. Good luck!

 

[BIGSAGE136]

Early in my diving career I had a fairly similar experience (pins and needles and other sensations in hand/wrist/forearm) that occurred about 16 hours after a dive that normally would not be expected to pose any bends risk.

Amazing coincidence. Saturday last I awoke and said to myself,
"Had I not been diving I would swear I was bent" Same sensations. Had a cup of coffee and smiled to myself about all of things I need to keep track of and in perspective as I grow wiser.

Stretch, and keep that tank low.

Safe diving.

 

[gazza]

Ok, to expand, i'm 34 reasonably fit in as far as i go to the gym several times a week, but overweight. i've been diving for about 2 years and have done just over 80 dives, most in the region of 10 to 35mtrs.

the first bend was after an evening/after work dive at the local lake, to do some twin set practise. a couple of hours after the dive i started to get a pain in my hand while i was driving. at the time i put this down to the shutdown drills i had been doing and didn't think a great deal about it - by the morning it had gone and i didn't think anymore of it until after i drove to work and started to get a pain in my arm. again i didn't think too much of this as it did subside after i got to work. however, the next day, the pain returned and steadily got worse with the altered sensation in my arm.

Once i got into the chamber that day, the symptoms diminished as soon as we got down to 6mtr and had pretty much cleared after a 5 hours pot ride.

The doctor put this bend down to the ascent i had after about 10mins. my buddy ascended while performing a midwater shutdown from about 6~8mtr,and i slowly followed. once on the surface, we stayed there for a minute or so and re-descended.

One thing that did make me think about this dive was as i was exiting the water up a beach, i ended up doing something which made me stain. i'd read an article about pfos and a reverse shunt. as i did whatever i did, i did think if that doesn't cause a reverse shunt i don't know what will.

the second bend was 3 dives and two months later. about 4 hours after a single morning dive, i started to feel very tired and spent most of the late afternoon / evening dozing off. Again, i had a slight pain in my hand, but i really didn't think it could be a dci after an 11mtr dive on 40%. However, the pain(s) developed over the next day or so until i found myself back in the pot. Again, the pain pretty much cleared once we got down to 6mtr.

i was symptom free after the first treatment, but a couple of hours after the second treatment the next day, the symptoms returned and a 3rd treatment made no difference. The symptoms dissapated over the next week - which was probably the worst & scariest week of my life.

now, i think i was pretty well hydrated for both the dives, with water and sport drinks. i try to make sure that i don't do anything strenious before or after the dives and i'm in no real hurry in the water. i also try and avoid going to the gym the day before diving or the same day as a dive.

HTH,

gaz.

 

[Dr Deco]

Dear gaz:

You have an interesting problem here. Speaking from a physiological point of view, that is not much of a dose of nitrogen to give a DCS problem. This is with reference to gas bubbles formed in place (autochthonous bubbles).

From the viewpoint of arterial embolism, it is not likely that this problem would appear so many hours later. In addition, and embolic event would not appear in the same location; that would be a low probability for an embolic event.

It really sounds as though it is a stress problem on the musculoskeletal system (my next best guess).

Dr Deco :doctor:

 

[gazza]

Thanks for the response Dr Deco.

Of course the next question if it's not a bend and could be a musculoskeletal problem, what should i do next?

 

[DocVikingo]

I must say that this sounds like non-DCI related musculoskeletal involvement to me as well, although the response to recompression puzzles me a bit.

I'd like to hear your musings on gazza's report of:

1. Symptom diminishment after the first event as soon as 6mtrs had been reached in the chamber with near total relief after a 5 hour protocol & no reported recrudescence. And,

2. Near total relief of symptoms after the second event months later after reaching 6mtrs in the chamber (although there was later recrudescence).

Thank you.

DocVikingo

 

[Dr Deco]

Hi Dr V and Readers:

DocVikingo has asked some interesting questions which do not admit to easy answers. Even in a research setting, we will have difficulty making a determination of DCS in some cases when there is a possible confusion with a musculoskeletal injury. This is despite the fact that we have Doppler bubble data available and prompt recompression available.

[1] The gas loads with respect to dissolve tissue nitrogen are very small. This makes a problem with a peripheral nerve quite small (although not impossible).

[2] With the strain and a passage of bubbles into the arterial system is certainly a possibility (as you mentioned) I would be very surprised that this occurred twice, on different occasions, with the flow of bubbles to the same location for embolization.

[3] It is not unusual that sprains or musculoskeletal stress can occur with a new task. Runners who often go five miles a day might find a pain if they start to run seven miles, for example. Any new task could have provoked a problem in your arm.

[4] Many pains from musculoskeletal injuries do respond to hyperbaric oxygen. Edema formation can occur, capillaries are closed (a compartment syndrome occurs), and hypoxia results. The cycle can be broken with hyperbaric oxygen, and the pain and swelling remit. The speed with which this occurred seems surprisingly fast, however.

[5] If the problem is an injury from a repetitive task, I might expect a reoccurrence in the same location. In short, I suspect that it was treatment of an injury with HBO but not treatment of DCS.

Dr Deco
On vacation this week :mean:

 

[DocVikingo]

With respect to the present case & my inquiry, I find your points #4 & 5 thought provoking.

Do enjoy your no doubt well-earned vacation.

DocVikingo