DCS

[duttonv]

What time time frame will undiagnosed DCS start revealing itself?

I did not have any sysptoms after the dives or on the flight home 24 hours later.

My last dive 6 weeks ago and since then I have had the flu, bronchitis, and am now having joint pain in my hands.

My dive profile met all no-deompression limits and the deepest I went was 64 feet in 75 degree water I did a saftey stop for 4 minutes at 15+- feet.

Additional info, I limited alcohol consumption to approx 1 1/2 drinks two or more hours after each day of diving was complete.

 

[Dr Deco]

Dear duttonv:

Decompression sickness is not something that persists for long periods in a latent form, since the gas phase is not stable. It will shrink away for two reasons:

• the body is slightly undersaturated (“inherent unsaturation”) and,
• the effeects of surface tension.

Several hours is about all one could expect for bubble lifetimes.

This is somewhat different from the persistence of the signs and symptoms of DCS, however. Here we are probably considering more than the gas phase. Blockage of blood vessels will set up a series of events in which a reduction of oxygen in a tissue will lead to the seepage of fluid (edema) out of the capillaries and into the extravascular space. This will lead to a slight swelling, not unlike what might occur in a sprain. This fluid leakage can persist for hours or days, and it is not shrunk by pressurization. It can sometimes be reversed by high-pressure oxygen in a hyperbaric chamber. If nerves are involved, the reversal may not occur until too late, after nerves have died. This is why rapid pressure treatment is always stressed when DCS (especially in its neurological forms) is encountered.

Can you get DCS days or weeks after diving? No, not really. The only manifestation of which I am away is aseptic osteonecrosis (= “bone death without infection”; it can also occur from steroid use and excessive alcohol consumption). This is something referred to as dysbaric osteonecrosis. It manifests itself only in caisson workers (under water tunnel workers) or commercial deep-sea divers. I know only one case on a recreational divers and that person was a dive guide for eighteen years when diagnosed by a diving medicine specialist (in Hawaii).

People have been know to notice pain a day later after diving when traveling by air (cabin pressure = 8,000 feet equivalent pressure). This is a depressurization however the evokes the presence of a silent gas phase. This “bubble” would almost assuredly not gone one to manifest itself as DCS without the air travel. (“ Let sleeping bubbles lie.”

Dr. Deco

 

[scubadoc]

Hello duttonv:

Any condition should be regarded as a decompression accident until proven otherwise arising within 36 hours of surfacing.

The diagnosis should be made by history alone without extensive, time-consuming x-rays and 'studies'. A quick neurological exam can be just as revealing as CT, MRI or HMPAO scans. There may be no abnormal physical signs.

Blaming other things for DCS is common. An unnecessary recompression is usually harmless whereas delayed treatment leads to worsening of DCS and decreased effectiveness of treatment.

In air diving, the latency of onset of DCS is as follows:
50% in 30 minutes
90% in three hours
99 % in 12 hours
100% in 36 hours

Cerebral DCS ( This is better perfused and more likely due to bubbling than to due to gas loading)
1.) rapid onset - 75% within 10 minutes of surfacing
2.) More complete spontaneous recovery
3.) May disappear with 100% O2 only to recur hours later.
4.) Secondary deterioration can occur within minutes to hours

More on this web page:
http://www.scuba-doc.com/brdprp2.html