Paranoid of getting the Bends

[japan-diver]

According to your description I beleive your were bent, you suffered a minor skin bends hit, many of these types of hits go unreported and even when reported they do go away on there own. The rash on the chest is a classic sign of this type of hit. There are a few preventive measures-

1. Nitrox is a great assest in the range you are diving
2. Slow ascent rates- with a safety stop at 50% of max depth and short stops every 10 ft from there up (30 seconds to a minute), final stop at 15-10ft depending on surface conditions for 3-5 minutes. If you do not have a watch or computer that can be set to an ascent rate of 30ft per minute get one- even if you just use it to monitor ascent rates its worth it. I find many divers who are watching their watch and depth gauge think they are going up much slower then they really are. Its hard to ignore the beeping computer if you are paying attention- one that downloads and give you good feedback on exact ascents rates is also good so you can really see what you are doiing.
3. Hydration- you were up earlier to drive to the boat, out on a boat all day in the sun diving twice breathing dry air. Lots of water, drink a lot the day before diving and continue throughout the day, especially after the first dive.
4. Fitness level- be honest with yourself and if you need to exercise more do so the better in shape you are the better your body will handle the dives.

Your dive profiles sound conservative enough for a resonably in shape person but some of these added safety factors may help.

 

[dumpsterDiver]

Wow! all good advice (for once).

Get checked
Use Nitrox
Do deep stop
Follow a computer for help in maintaing ascent rate.
Drink a lot on the way to the dive site and on the boat.
Are you in shape?

 

[TSandM]

This sounds like mild DCS to me, and as an ER doc, I can tell you that most of us have little or no training in recognizing or managing it, so the fact that you were cleared out of the ER gives me little confidence that we can be sure it wasn't the bends.

Do you dive a computer? What did your computer think about the profiles and the ascents?

You did quite a bit more deco than standard recreational training would suggest, but the distribution of it was rather Haldanian, in that you went shallow fairly quickly and did your time there. What bubble model theory says is that there is a flaw in that approach, which is that pushing the gradients (as you do by getting up shallow) results in the growth of microbubbles, and the gas trapped within them is far more difficult to offgass than gas which remains in solution. This is the purported benefit of deeper stops, and I wonder if you might have been better to have spread your time out between 50 fsw and the surface, rather than doing it shallow.

What I think you do know, as a result of this, is that for your particular physiology (and at least on that day, with fatigue and maybe a bit of dehydration in the mix), these profiles were overly aggressive. One of the things that experts in decompression say over and over again is that there is much we don't know, and some things are variable from individual to individual. Even experienced technical divers adjust their decompression profiles to the data they gather on themselves.

Diving Nitrox should help a lot, if you want to continue doing these types of profiles. Ensuring you are in good physical condition to dive (not fatigued, dehydrated, or badly out of shape) will help as well. Changing your ascents to a more gradual curve MAY help, and adding additional decompression time, particularly on the second dive, is probably wise as well.

If you have another episode like this, a PFO test may be in order. The difficulty with recommending PFO screening is that, although the relative risk seems to be higher in people with PFOs, there are clearly many, many divers out there with PFOs who are not getting DCS, and some divers who are getting DCS who don't have PFOs. The transesophageal echo is an expensive test which is often not paid for by insurance, and has some minor risks. Transcranial Doppler may be almost as accurate, but is available in far fewer places.

Having had a cardiac cath gives you very little information. To see a PFO, you have to create conditions that promote right to left shunting, and you have to be able to see the shunt. Contrast arteriography is not the best way to do this, and rarely, during a cath, are you asked to Valsalva or otherwise raise right sided pressures.

 

[nereas]

I think that was what I said?

You must have been thinking of George Foreman!

 

[nereas]

...On my first dive my maximum depth was 91 swf although I kept my nominal depth between 77 and 83 swf. After 25 minutes I started my ascent at a rate under 1 ft every 2 seconds. Keep in mind this was a drift dive, so there was no anchor line to make my ascent on. It was purely finning up and keeping an eye on my depth gauge. At 30 swf I made a safety stop for one minute and a five minute safety stop at 15 swf. My total surface-to-surface time was 38 minutes. I had a 1 hr, 2 min surface interval between dives.

On my second dive my maximum depth was 78 swf keeping a nominal depth between 66 and 75 swf. Again, after 25 minutes I ascended at the same rate making a one minute safety stop at 30 swf and a five minute safety stop at 15 swf. My total surface-to-surface time was 37 minutes.

As I was driving home, I started getting a rash on my chest and abdomen about two hours after the last dive. An hour later I got those headaches that cause part of your vision to get blurred. Needless to say, I thought, “Oh s__t! Am I getting the bends?” But after a while, both of those symptoms went away. Then I started feeling tingling sensations in small areas of my arms and legs, but there was no joint pain...

That night I woke up at 2AM and started getting really scared because I had a 2 hour flight scheduled for 7PM that day and still had some tingling in my bicep and still felt wiped... I called DAN ... and relayed my situation. The dive physician on the line believed I didn’t have DCS, but suggested I go to the emergency room in the morning.

After spending four hours in ER where they took blood, x-rays, and an MRI of my head, the attending physician who had experience in dive medicine said it didn’t look like I had DCS and cleared me for flying that night.

Now my wife, who hates me diving to begin with, went ballistic since this was the second time something like this has happened and strongly recommended I give up diving...

I would call these "mild" DCS sypmtoms, aka Type 1 DCS.

And I would agree with the DAN doc, that you would not need recompression treatment.

But you clearly should modify your diving procedures, like I said, such as adopting nitrox, which effectively decreases your maximum depth by reducing the inert gas (N2) uptake.

I have dived your dives many times on air without problems of any kind. And I am about your age as well. But I only dive air when I cannot get nitrox.

Everyone immediately thinks of PFOs whenever someone shows mild or strong DCS sypmtoms from an otherwise ordinary dive. It could be that, and it also could be simply that you were dehydrated that day. A lot of things can cause mild DCS symptoms.

 

[banjoman1948]

There has been quite a good bit of information conveyed in this forum. I do have a dive computer, but I don't have the software to download my dive profiles onto my PC. That's going to be my next dive equipment purchase.

The next thing is to sign up for nitrox classes. I've had a lot of people in my age group (55 and older) say breathing nitrox is better for you. I know I'll have to convert my air tanks to nitrox which can be done at the local dive shop. Do I have to get my regs and hoses cleaned as well?

 

[TSandM]

In general, you don't have to have Nitrox compatible regs/hoses. The reason you have to have your tanks and valves O2 cleaned is because a lot of shops mix Nitrox by partial pressure blending -- they put pure oxygen in the tank and top it off with air to make the mix. Thus everything in the tank and valve has to be clean enough to tolerate pure oxygen under high pressure. Stuff past the tank valve (first and second stages, and hoses) will never see any more than 40% O2.

 

[nereas]

For recreational nitrox, your regs and hoses should be fine as they come from the manufacturer.

Check with your dive shop about your tanks.

Enjoy the class! It is the gate to even better understanding of how scuba gasses work inside of your human system. You will get a better appreciation of no-decompression limits, their depths, and their times.

 

[Iceguy4]

Is the test you're referring to called a Transesophageal echocardiography? From the info I got from the above web site, this test involves swallowing a flexible tube with a recording device that captures ultrasound images. This is the best test for detecting a patent foramen ovale.

This doesn't sound too uncomfortable.

I just had the test...kinda hurts but you have to stay awake to swallow the device. They gave me something in my IV line...didn't work. Why don't they use kriptonite. everyone knows thats the only thing that works!!!

 

[banjoman1948]

How did you make out with the test? Did they find a PFO?