Asthma question

[Kay]

I know you have already talked about asthma before, but......

I am in the middle of my SCUBA training and will be certified by the middle of next month. I spoke with my ENT about my previous medical history [sinus surgery 20 years ago, and asthma that has been upgraded to irritable airway] and diving. After giving me a horror story about exploding lungs, she said that she'd give me the okay to dive. She suggested that I don't 'dive too deep.' She then told me that she has asthma and dives regularly. I don't have to take medication for asthma any more and haven't for years. I hardly ever use an inhaler. My one asthma attack that required medical intervention occurred when a herd of elephants ran into a circus in a small, enclosed area and the dust hit me.

I just don't want to have a lung explode near some remote island. That would definitely not be cool. However, it sounds like lots of people with asthma or 'irritable airway' dive. I would be interested in two things: 1] what is your opinion of my situation and 2] is there a specific depth below which asthmatic divers shouldn't go--i.e. is there a safe or safer depth?

Thank you very much.

 

[Drew Sailbum]

As to question 2:
The greatest risk of air embolism is nearest the surface. This corrolates with a greater percentage change in volume at shallower depths. Avoiding deeper dives does not change this situation.

There is a very slight increase in breathing effort with increased depth. This arises from the increased pressure and thus density of the air with increasing depth. This may be an issue but, IMHO, if the differing density of breathing gas within recreational depths is enough to trigger an asthma attack, then you have no business diving.


As to your situation:
I'm glad to see that you have discussed your medical history with an ENT. The exact nature of your past sinus surgery should be evaluated as it pertains to pressure equalization whilst scuba diving. An ENT is probably most qualified to do this.

Your history of asthma is also a concern. While an ENT may have some expertise in this area, I would think a pulmonologist with a knowledge of dive medicine would be the ideal expert to evaluate your situation.

 

[fmerkel]

You might want to read this:
http://faculty.washington.edu/ekay/asthma.html

Also, do some searching on the DAN website.

It won't answer all your questios but its a start. Basically you have to have VERY good control over the asthma and be acutely aware if it is acting up at all. If you dive particular emphasis should be place on slow, controlled ascents. Depth per se is not an issue. Any depth on compressed air can cause a problem, even in normal people that hold their breath on ascent. The issue with asthma is irritable airways closing up under the stress of cold dry air and exercise and "holding your breath" for you unawares.

Fritz

 

[medic_diver45]

I asked a similar question several months ago of one of the pulmonologists I worked with (who is a diver AND asthmatic) and his opinion (and he said it was based on the DAN standard (I haven't read that- so correct me if this is wrong) was that if the person had been symptom free (not requiring the use of a inhaler for acute exacerbations) for a period of 12 months and pulmonary function tests were normal he would not hesitate to sign off on them diving. He went on to say that he thinks most of the "you shouldn't dive with this standards" are written to: "cover the *** of the agency handing out the license more than protecting someone. There is no reason why a reasonably healthy person should be kept from doing what they want to do just because of an asthma diagnosis. C'mon they take cripples diving for Christ's sake to make them feel better about themselves. There's more risk in doing that than with letting someone with asymptomatic asthma dive"

Of course, that's his opinion (I happen to agree; my opinion is you should be able to dive if you want, after all it's your a--. ) You should listen to whatever you're doctor says in best in your particular case (I have to include the standard disclaimer just to cover myself in case something does go wrong).


Semi-related question: Have they ever come up with a way to humidify the air in SCUBA units? I was wondering this the other day....I really need to find better things to occupy my time with....LOL

 

[medic_diver45]

By the way, if anyone takes offense at the doc's use of the word "cripples" instead of handicapped or physically disabled or other such PC BS.....remember two things:
1. He said, I didn't (I just repeated it to maintain the integrity of the quote.)
2. Changing the name of the condition doesn't change the nature of the condition...

 

[fmerkel]

Sure, there is a humidifier:
http://www.apollosportsusa.com/products-regcomp.html

It's expensive and I have no idea how well it works.

Some regulators (Sherwood Oasis) have some "condensation vanes" that are supposed to help. My wife had one but prefers the performance of her Scubapro more. Again, don't know if it helps much. Supposedly steel case 2nd stages do a bit of the same thing.

I used an Alpha Omega side discharge 2nd stage for awhile. They tend to breathe "wet" as the collected water inside has no where to go and tends to atomize on the inhale. Poseidon would probably do the same thing.

Standards can be a difficult thing with asthma. It can be kind of "slippery". Asthma is not always stable over long periods of time. I have several friends with asthma that dive. In general they are pretty mild. One though, sometimes has a bad attack and will be sensitized and a mess for weeks to months. In between these times she is symptom and drug free and fine to dive in my opinion. Since she certified in her college years before this became a problem (70's) she doesn't have to ask anyone's permission or get clearance BUT for her own safety and health she needs to be very clear when she is OK and not.

Fritz Merkel
Respiratory Care Practitioner
FWIW-I teach asthma management and have been diving for 10 years/500 dives. I occasionally get a cold and have cough variant asthma and take inhaled steroids. No diving during these times.

 

[scubasusan]

I have a Sherwood "wet breather" and I love it. I'll never go back to the dry mouth that comes with other regulators.

Susan

 

[Drew Sailbum]

Certainly proper management of any pulmonary condition is of great importance. It seems so obvious to those experienced with diving. That said, sometimes poor decisions are made.

Not so long ago I saw a diver loaded into an ambulance. She was doing her first dive on the island and it was her first dive since certifying back in the USA. She has active asthma and had decided to not disclose that information to her instructor. As a result of her deception, she was not referred for a knowledgable physician to evaluate her case. She did, however, tell the dive crew and the paramedics only after she experienced a significant problem.


Asthma is not a condition to be trifled with. In some people it can be appropriately managed. For other people, asthma should be a barrier to all scuba diving. Please consult a physician knowledgable in dive medicine and have a honest discussion to properly evaluate your risk.

 

[medic_diver45]

Here's a question for you:
If you have a 23 y/o male patient (cleared by a pulmonologist (who is not familiar with dive medicine; but the patient does not have access to another doctor (one that would have more familiarity with the idiosyncracies of dive medicine) due to issues with insurance) who is technically a diagnosed asthmatic, but only in that he blew at 28% change on pre-/post-bronchodilator changes (the standard used by the PFT lab that did the tests (and what I was taught in school as well) says that a 25% or greater change is diagnostic for asthma (I know of some labs that use 30% as a cut-off to prevent overdiagnosing people (don't get me started on this one)) during a routine screening exam (everybody does a full physical every twelve months at a major discount courtesy of a local physicians group) for the volunteer fire department- the patient in question is one of my firefighters/EMT's BTW and was asking my opinion about whether he should dive or not (I was talking about learning to dive and got him interested in it). He is totally asymptomatic, in average to above average shape (he's ran and placed fairly highly in 5K races and plays soccer on weekends), exhibits no overt signs of shortness of breath or other distress when breathing cold dry compressed air from SCBA's, and is very comfortable in the water (he is trained in swiftwater rescue). He does not get short of breath when exposed to the heavy smoke, ash, and dust conditions that are experienced during salvage and overhaul operations on firegrounds.

The physical exam and blood work revealed no other pathological abnormalities (elevations of glucose and lipids were found, but are attributed to a failure to fast)- in fact the doctor's only concern other than the PFT results was a marked bradycardia (resting heart rate of 44) which is normal for a trained athlete such as this patient. The only other parameters outside normal were results above the predicted (pre-bronchodilator) values for forced vital capacity, FEV1, and FEF(25-75). Results for nitrogen washout and helium dilution were normal and unremarkable. Airway resistance (Raw) results were normal. (For all you HIPAA fans out there, I have the permission of the patient in question to discuss this here....I asked him if he would mind if I posted this information with identifiers removed so that I might garner dive medicine professionals opinions on his case.)

I gave him the standard spiel of it's up to your doctor to give you official go-ahead, but I said I didn't see any reason that would make me as a respiratory therapist be concerned for his safety any more than I would be for any member of the general public.

I know the pulmonologist personally (I have worked with him in addition to his being a family friend) and trust his opinion almost without question (there are not many doctors I would say that about). He stated that he believes the patient to not be a "true" asthmatic due to his lack of symptoms despite repeated heavy exposures to common triggers, but rather that he is exhibiting a reaction to the bronchodilator that is sometimes seen in moderately well trained athletes (I wasn't familiar with this explanation and I am trying to cross reference it in my copy of Ruppel's text on pulmonary functions- my experience in the PFT lab was limited to testing mostly out of shape Air Force personnel so I have not had much practice looking at the results from someone in above average shape.) This does not sound too outlandish given the facts presented above and I am inclined to agree with the doctor.

I consider this young man a close friend and one of the best firefighters in our area (he's better at it than I am, and you don't hear me say that about very many other 20-something volies) so I am genuinely concerned about his safety and do not want to misguide him. I just don't want to make a bad judgement call on this and have to answer for it later (not in the professional sense, but in a personal sense- if something happened to him, I would never forgive myself). What is everyone's take on this? Should this patient dive?

 

[medic_diver45]

It should also be noted (but I forgot to mention it above) that I asked the pulmonologist whether he felt a bronchoprovocation (i.e. methacholine challenge) test should be performed in this case to definitively rule out the possibility of occult asthma and he stated (and I agree that) the risks for such testing are far greater than any potential benefit from such a procedure due to the patient's lack of any symptoms. This further supports the contention that the pulmonologist does not feel that he is an asthmatic.

He has been prescribed an inhaler (by the family practice doctor who initially assessed him) to keep with him in the event of a sudden exacerbation, but in the three months since the test he has yet to have to use it and the pulmonologist told him he does not need to carry it with him if he does not wish to do so.