How long to wait after DCS?

[Bwanap]

In January 2008 I got a mild case of DCS while in Cayman Islands. Went a few minutes into decompression on a dive and stayed down until my computer said clear, (although on dowloading it showed I wasn't but that is another story). Had pain in my left elbow that eve and went to hospital. Oxygen helped, so I got the standard 5 hour recomp treatment and although it did not resolve entirely in chamber, was better and improved further next day. Back home had a follow up treatment for 1.5 hours (I think). Docs in Cayman said very mild case, can dive again in 3 months, just take it easy.

After 4 months taught a course, which involved not being able to take it easy, cold water, lots of students. A few hours later I had pain in the elbow again. I went for a 5 hour treatment and two follow ups with a local hyperbaric center (not diving specialists, but near my house and they got all the info from Doc at area specialist- Swedish Covenant in Chicago).

My question is how long should I stay out of the water now? The doc at the center can't say, my GP can't say and even if I went to a diving specialist, what could they say other than checking if there are any lingering neurological issues (I am pretty sure there aren't as the elbow was the only symptom I ever had). I understand that there is no specific way to know, but what is recommended, a year, two five, ten, ever?

 

[DocVikingo]

Hi Bwanap,

It might be a prudent idea to have an orthopedic or sports medicine specialist examine the elbow as it's possible the discomfort is being caused by stress-related injury and not by DCS.

As for return to scuba following an incident of DCI, here is what DAN has to say:

"Although United States Navy return to diving policy was not written for recreational divers, it does give us the following guidelines to consider (specific Navy policy recommendations are in quotes):

1. Divers with uncomplicated, pain-only DCI cases and whose symptoms resolve completely after 10 minutes breathing oxygen at 60 feet/18 meters can return to diving after 48 hours of being symptom-free.

This is probably a little too aggressive for recreational diving. Two to four symptom-free weeks is usually recommended for recreational divers.

2. An uncomplicated pain-only DCI, divers who have had a completely normal neurological exam prior to recompression and whose symptoms took longer than 10 minutes to resolve, the Navy allows a two-week wait before a return to diving.

This may be too soon for recreational divers, who may return to multiday repetitive diving. A minimum wait of four weeks is a more conservative option.

3. If divers have had cardiorespiratory or neurological symptoms such as weakness or numbness, the Navy recommends a four-week waiting period.

A six-week symptom-free minimum wait may be more appropriate for recreational divers.

4. In more complicated DCI cases, in which symptoms seem to resist treatment or in which long treatment tables such as Table 4 or Table 7 are required, the Navy requires a minimum of a three-month layoff from diving. Diving may resume only after a thorough review by a Diving Medical Officer.

For recreational divers who experience DCI this severe, giving up diving altogether may be appropriate. At any rate, recreational divers should take a six-month hiatus from diving, followed by a thorough examination by a dive physician.

For recreational divers who want to dive after experiencing DCI, here is the best advice:

Wait until you have been free of symptoms for four weeks; and seek evaluation by a physician to determine whether there is some predisposition to decompression illness."

Helpful?

Regards.

DocVikingo

This is educational only and does not constitute or imply a doctor-patient relationship. It is not medical advice to you or any other individual and should not be construed as such.

 

[Bwanap]

As I had been hanging onto the dive platform in fairly rough seas, an injury to my elbow was certainly a consideration at first. But the examination at the hospital showed no indications of a strain injury and the recompression treatment eventually helped in both cases. I have been symptom free for almost a year now, although there have been one or two times I felt a slight something in that elbow that may have occurred at times of weather changes.

I wonder if the DCS can leave scar tissue that could be susceptible to or cause an arthritic type condition? Could potential scar tissue make that elbow more susceptible to DCS in the future? If either is true is there anything that can be done to diminish this likelihood? My plan when I return to the water is to dive conservatively with nitrox, and make sure I am hydrated. Other than that I do not have other contributing factors (other than age which I can't do much about). Any other suggestions for reducing risk?

 

[DocVikingo]

Hi Bwanap,

That "the examination at the hospital showed no indications of a strain injury" certainly is a good thing, but was this the conclusion of an orthopedic, sports medicine or other kindred specialist made after a full and appropriate assessment?

On occasion, recompression treatment may "eventually help" joint and connective tissue injury that is not the result of DCS. The mechanism for this is not clear, but the swelling that accompanies such injury can compromise blood circulation and decrease oxygen perfusion, a situation that could be partially offset by 100% 02 administered under hyperbaric conditions. There also is the matter of the natural improvement that is expected in such injury with the passage of time.

A history of direct trauma to a joint does appear to predispose to the development of joint-pain DCS. And, while the evidence is weak, a history of a prior incident of joint-pain DCS may leave one more susceptible to experiencing another.

Concerning scar tissue, it has been hypothesized (real proof is as yet absent) that scar tissue may decrease gas diffusion and predispose to DCS. As regards DCS itself resulting in the formation of fibrous scar tissue or a true arthritic condition, I know of no evidence to support this.

I'm going to ask Dr Deco if he'll offer his opinion on your inquiry.

Helpful?

Regards,

DocVikingo

This is educational only and does not constitute or imply a doctor-patient relationship. It is not medical advice to you or any other individual, and should not be construed as such.

 

[Dr Deco]

Hello Bwanap:

Sorry for the long delay; I have been out of town.:cool2:

Oxygenation

There is good evidence that tissue swelling is improved with hyperbaric oxygenation. Fluid balance in tissue has a metabolic component that depends on the movement of sodium ions. When blood flow is compromised and oxygen is in deficiency, this pump does not function. It can be restored by forcing oxygen into solution and allowing it to diffuse to the hypoxic areas. Sprains and strains are often thus helped. Naturally, "tincture of time" is helpful.

DCS and Trauma

There is evidence that a severe injury can predispose to DCS. An example is falling on one's knees from a motor cycle. Small injuries happen to everyone and do not seem to be prognostic, according to an US Air Force case study.

It is also true that susceptibility to DCS varies amongst individuals. Experiencing DCS might indicate that the diver is in the more susceptible grouping.

Certainly, the formation of scar tissue would promote diffusion as the nitrogen elimination mechanism. Unless there are nerve cells, however, scar tissue would not give evidence of pain.

DCS and Injury

DCS can lead in commercial divers to aseptic bone necrosis. I have never heard of arthritis resulting from diving.


Dr Deco :doctor:

 

[DocVikingo]

Hi Bwanap,

Seems that you've received two largely consistent professional opinions, and this doesn't happen very often ; )

Seriously, hope the information provides food for thought and suggests some possible courses of action.

Best of luck.

DocVikingo

 

[Bwanap]

Yes thanks for the info. One more question though, given the relatively short periods of time presented, is there going to be any added benefit to waiting say two years versus one before diving. All other things being equal.

 

[DocVikingo]

Hi Bwanap,

I am not aware of any research addressing this particular timing issue. However, it seems quite unlikely that waiting two rather one years before resuming SCUBA would add any meaningful benefit.

Regards,

DocVikingo

This is educational only and does not constitute or imply a doctor-patient relationship. It is not medical advice to you or any other individual, and should not be construed as such.