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Nitrogen Narcosis psychology Column by IMAGES THIS PAGE COURTESY OF DIVEPSYCH.COM David F Colvard, MD Nitrogen Narcosis Nitrogen narcosis, or “rapture of beginning of exposure to compressed air the deep,” is one of those things and did not change with time at depth. In other words, breathing compressed air that some divers like to joke at depth makes you stupid and slow and about but really is no laughing clumsy, not exactly worthy goals. matter. (Pun intended) While a In the winter of 2004, I conducted a recreational diver is far more poll of 1,984 divers and asked, “In 2003, did you experience nitrogen narcosis likely to experience nitrogen on any dive? (light-headedness, eupho- narcosis than decompression ill- ria, elation, laughter, poor coordina- ness, we know much less about tion, slowed thinking, poor judgment, or If you want to kiss a jellyfish, you are narced for sure the exact physiological mecha- reckless behavior)” and at what depth they began to experience it. Only 20% less susceptible to nitrogen narcosis me he stopped diving on the West Coast nism of nitrogen narcosis than of males (n=1,523) and 18% of females or “stupidity of the deep” than you. because he no longer felt safe in the that of DCI. Unfortunately, both (n=461) admitted to having any signs or For starters, remember the “Mar- water with so many “high” divers. I hope can result in a diver fatality, the symptoms of nitrogen narcosis while div- tini Rule” that states that the symp- he was exaggerating the extent of the ing in 2003 and most of those reported toms of nitrogen narcosis are similar problem. first from being bubbly drunk that it began when they were deeper to being inebriated and that every Professional tech diver Bret Gilliam, who and foolish and the second from than 90 feet. 50 feet of depth is like having one made a record dive to 452 feet on air in being bubbled up. Is it possible that all the other divers martini. Therefore, the first thing 1989, developed a simple low tech test stayed above 60 feet on all their dives in you want to avoid is a dive buddy for nitrogen narcosis: Every few minutes, So, when we were on Bonaire a few 2003? Not likely. It is far more likely that who starts out the dive day with a hold up a number of fingers to your years ago on Father’s Day and my they under-reported their symptoms, couple of 50 foot alcoholic drinks or buddy (say, three fingers). He has to daughter, Stacy, gave me a T-shirt that either because they either failed to rec- who is still hung over from a night of respond with the same number plus one read, “I’ve got nitrogen narcosis. What’s ognize them or to remember them. There heavy drinking. Just like there is no (four fingers). “If you really wanted to your excuse?” I was not quite sure how can be wide individual susceptibility to such thing as having “one for the screw a guy up,” writes Gilliam in his book to take the message. I assumed it might nitrogen narcosis. That is another good road’ when driving, there is no such Deep Diving, “you gave him all five fin- have been a critique of my fanatical reason to dive with a reliable buddy thing as having “one for the dive.” gers and then he had to use both diving. Surely, she could not have been so you can check on each other. Just Antihistamines, antiseasickness hands to come up with a six-finger re- referring to my charming personality. That make sure he/she is less susceptible than drugs and patches, sleeping pills sponse.” So, if you want to check on your is one of the big problems with nitrogen you. Fortunately, the impairment from and some other medications can dive buddy’s state of nitrogen narcosis, narcosis. You probably don’t even know nitrogen narcosis resolves rapidly with multiply the sedative-hypnotic- then ask him or her to give you more than you have it at the time. decompression. Of course, this assumes like effect of nitrogen narcosis, so one finger. In 1935, Behnke et al found that even you have not already gotten yourself into you can risk diving stupidly and slowly watch out for those, too. Marijuana also David F. Colvard, M.D., is a private at just 66 feet (3 ATM), breathing com- trouble thinking you are invincible. and clumsily at more than 60 feet (3 emphasizes the anesthetic-like action of psychiatrist and clinical investigator in pressed air produced “euphoria, retarda- ATM). Or, you can dive relatively safely at high pressure nitrogen at depth. It is best Raleigh NC, and a divemaster. He hosts tion of the higher mental processes and Recognizing the signs less than 60 feet all the time. And last but to avoid it and divers who use it if you www.DivePsych.com which provides impaired neuromuscular coordination.” According to my poll in 2004, over 80% of not least, you can dive with a dive buddy want to dive safely. evidence-based information for divers on At 100 feet (4 ATM) he found even more scuba divers fail to recognize or remem- who will check on you. Whoa, I knew Back in 2000, when I started doing psychological and stress factors in scuba impairment in divers. What is especially ber having any signs or symptoms of nitro- there had to be a reason for the buddy research in scuba diving, a retired inter- divers. ■ scary is that it occurred from the very gen narcosis. So, what can you do? Well, system. This assumes your dive buddy is nationally renowned diving scientist told 60 X-RAY MAG : X : 2006 EDITORIAL FEATURES TRAVEL NEWS EQUIPMENT BOOKS SCIENCE & ECOLOGY EDUCATION PROFILES PORTFOLIO CLASSIFIED.
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