Asthma and Scuba Diving
In general, asthma is a lung disorder in which there is a tendency for the muscle surrounding the bronchi (breathing tubes) to contract excessively, causing narrowing, or broncho-constriction. As a result, this causes increased breathing resistance, which can manifest as wheezing, chest "tightness", cough, or breathlessness. In asthmatics, broncho-constriction can be precipitated by exposure to allergens, noxious fumes, cold air, exercise or respiratory infections such as a "cold". People with asthma may experience broncho-constriction due to more than one of these factors, but many asthmatics will experience a measurable increase in breathing resistance after exposure to any one or several of them. The increase in breathing resistance caused by bronchial narrowing may be compounded by the accumulation of mucus within the airways.
- During scuba diving the diver experiences a reduction in breathing capacity due to the effects of immersion and an increase in breathing resistance caused by the higher gas density at depth. At 33-feet underwater, the maximum breathing capacity of a normal scuba diver is only 70-percent of the surface value. At 100-feet underwater, this reduction is approximately 50-percent. If, for example, a diver’s breathing capacity is already reduced because of asthma, there may not be sufficient reserve to accommodate the required increase demanded by exertion.
- Both narrowing of the bronchi and excessive mucus production can inhibit exhalation of air during ascent, and could predispose the diver to pulmonary barotrauma leading to pneumothorax, pneumo-mediastinum and/or arterial gas embolism.
It is important to note that asthma severity can wax and wane. Symptoms may worsen for 4-6 weeks after a "cold" or during certain seasons (for example in response to high levels of pollen in the air.) Therefore, even if a person with asthma fulfils the criteria listed above, diving is not recommended unless the diver is free of respiratory symptoms before each dive.
Hi. I was diagnosed with asthma when i was very young and have lived with it for many years. I am not medically trained at all and the severity of asthma will obviously differ for people. I have been diving for approximately 6 years now and am happy to say that my asthma has never limited me in this. I have no idea what it's called (again, no medical training) but when i did my medical before obtaining my diving certification i was given a device that i can use before a dive to test my own lung capacity at that point in time. It's simply a device that you blow into with a marker moving up and down on a gauge indicating lung capacity. The doctor recommended a minimum level of capacity that, if not reached, to refrain from diving on the day but, if above, to go ahead. I have never had any challenges diving. I don't want you to endanger your daughter because of one opinion but i know there are people suffering from asthma that dive and have done so safely. I always brief my buddy about my condition and if my breathing feels strained i abort my dive. I hope this helped :)
I also suffer from asthma, more specifically exercise induced asthma. With my doctor's help, we have been keeping it under control up to the extent where I cycle and dive without any issues. Off course each patient has his or her own unique situation, so you need to work closely with your doctor and more importantly you ahould know your body. As stated by Rachelle, brief your buddy about your asthma and also the dm and skipper. As an additional safety precaution, I take my inhaler along and leave it with the skipper. I have also heard about underwater inhalers, but I have not done any research on them.