Down deep, most smokers realize they shouldn’t smoke, but they find it very difficult to quit. Many rationalize, thinking they can always quit if their smoking causes any medical problems. When you’re young and healthy, lung cancer and heart disease seem to be a long way off. These are the diseases of old age, and maybe you’ll quit smoking when you reach 40. Until then, maybe you can get by with a few more days, weeks, or years of smoking.
There is no choice for the diver. He or she should quit smoking right now – or consider giving up diving. The hazards confronting a smoking diver are much more immediate and potentially more lethal. Mixing smoking with diving is just about as risky as drinking alcohol and flying a plane. Among the dangers which can be induced by smoking are such physiological problems as: involuntary hyperventilation, overexhaustion, lung overpressure and maybe even air embolism. The scariest part of this is that it happens inside the body: You can’t see it, and, you probably won’t realize what’s happening until it’s too late.
Every diver who has ever gone through a basic scuba class knows what a tremendously important role the respiratory and circulatory systems of the body play in diving. The heart and lungs are some of the most important organs in a diver’s body and they are linked together with the rest of the muscles and tissues by the circulatory system. The blood which courses through your veins and arteries is the key mechanism for life, for this is the delivery vehicle for transporting that life-giving supply of oxygen to big muscles in the legs, thighs and arms. Like microscopic boxcars, the hemoglobin in the blood stream picks up fresh oxygen at the lungs and distributes it to the hard-working muscles. On the return trip, it brings back carbon dioxide. A new scuba student devotes many pool and ocean training sessions to improving the physical fitness of his/her heart and lungs so that there is a more efficient delivery of oxygen-laden blood. A diver with a weak circulatory system is in trouble.
Smoking robs your body of much-needed, life-giving oxygen and thereby starves your muscles and tissues, causing severely reduced performance. Heavy smoking can cancel all the benefits which a person would normally receive from daily exercise, swimming and physical fitness training. Research performed by respiratory physiologists indicates a smoker’s circulatory functions are often decreased by 15 to 18 percent. It is this deprivation of oxygen which not only reduces the diver’s strength and stamina, but can also lead to overexertion, involuntary hyperventilation and possibly unconsciousness. A smoking diver is a setup for an underwater accident, for you have all the ingredients needed for a classic case of panic.
How does this happen? The culprit is a nasty character called carbon monoxide. The combustion or burning of an organic material, such as tobacco, produces carbon monoxide in surprising amounts. It is the same lethal gas found in automobile engine exhaust and can produce unconsciousness and death. Air pollution standards indicate it is dangerous to breathe air containing a carbon monoxide level higher than 100 parts per million, and air purity standards for scuba diving indicate that anything more than ten parts per million is dangerous. Yet, cigarette smoke can produce an incredibly high carbon monoxide level of 42,000 parts per million. Normal walking or sitting might not reveal any problems with this increased carbon monoxide uptake, but it could prove devastating while swimming at depth.
What does carbon monoxide do to your body? it is a well-known medical fact that hemoglobin has a tremendously high affinity for carbon monoxide – 210 times greater than its attraction for oxygen. Once carbon monoxide has entered the lungs and passed through the walls of the alveoli, it bonds itself with the hemoglobin in the bloodstream, much like iron fillings stuck to a strong magnet. Once hemoglobin is loaded with carbon monoxide, there is no place for oxygen and the blood’s capacity for carrying it becomes severely reduced. It takes more blood and a harder-pumping heart to overcome the effects of smoking. This condition generally goes unnoticed until the diver begins swimming hard at depth, thus causing his large leg and thigh muscles to work at peak capacity. Because of the reduced amount of oxygen flowing through the blood, the muscles tire quickly and the diver begins to huff and puff. He or she then nears panic as his/her lungs desperately try to force more oxygen through arteries which are loaded with carbon monoxide. Oxygen deprivation at depth can be one of the most serious problems facing a diver.
To complicate matters, we find that the effects of carbon monoxide absorption are surprisingly long lasting. It takes the body six hours to reduce the level of carbon monoxide by 50 percent, and traces of this contaminant can remain for 24 hours or more. If divers wanted to completely purge their bodies of carbon monoxide for a dive trip, they should not take a puff for at least two days prior to the event, and abstain from smoking until six hours after the dive, so that decompression functions can go unhampered.
If this isn’t enough to convince you to quit, let’s consider still another serious hazard linked to smoking. Apparently the nicotine and tar substances in tobacco smoke are potent irritants to the respiratory tract and sensitive lung tissue. Heavy smokers often awaken with a morning cough and spit up sizable quantities of mucus. This should be an obvious clue. It has now been discovered that smokers often develop small airway obstructions following minor respiratory infections such as the common cold. These obstructions or plugged-up passageways can often last for more than a month after the outward symptoms of the cold have passed. Such obstructions within the fragile tissue of the lungs can pose in lethal hazard to the scuba diver during ascent from depth. Should the air passage become clogged with mucus or collapse from pressure buildup, an air embolism could easily result.
Considering the volume of evidence presented by medical researchers, it would appear that divers have little choice in the matter. If a person wishes to pursue the sport of diving, he or she should consider giving up smoking.