I don't wish to worry anyone, but this whole lack of air for sexual fun concept is rationalising insanity. ! I can accept in principal, ideas of pleasure thru pain, even other forms of BDSM but playing with your life ! I Dare say even russian roulette could "be" sexualy arousing, but this my friends is bad . I see the attraction and understand the concept but there are better ways to express this without endangering your life! . Thrill of danger, the adrneline rush, fine, but the idea is to face this, overcome the odds and survive, not to put yourself in a life endangering situation and deliberately stack the odds against you because you think it is sexy ?
What Tania described may be a thrill, I don't know, but it is quite different from what is commonly known as erotic asphyxiation. Asphyxia is a lack of oxygen to the brain, however caused - it doesn't have to be from stopping breathing. You can find some entries on it in the academic literature, in advanced martial arts holds, in films such as 'In the Realm of the Senses' and in some self-deliverance literature (ie suicide methods for th terminally ill). In writing about it I am not in any way recommending it, but think it is good to be clear on what is what.
The method involves compression (on the neck) of the carotid arteries or jugular veins or both. The pressure needed to stop the blood flow is *far less* than is required to interfere with breathing so does not cause the unpleasant side effect of feeling the need to gasp for air - and herein also lies the danger. After a few seconds of pressure - it can be as little as 15 seconds - the lack of oxgenated blood to the brain causes unconsciousness and, if prolonged, death. The feeling is akin to swooning. When the carotid artery is pressed, it stops the flow of blood to the brain directly; when the jugular veins are compressed, it causes a 'road-block' so that the blood cannot circulate out of the brain to allow fresh oxygenated blood in.
People who engage in this (very dangerous) practice seek to prolong the moment before consciousness is lost, possibly timing it with orgasm. Getting it wrong can cause brain damage or death, and there is very little time for the recipient to indicate any warning, even if they are skilled at doing so. Possibly if both persons have advanced knowledge of the martial arts hold it could be done with a greater degree of safety but it is hardly a fun fetish - this is extreme sports.
Holding the breath (oneself) might be a safer way of trying to get a similar result. The body's automatic reflexes will cut in before you pass out.
Take care.
In reply to some posts , Cheating Death is an attractive buzz, extreme sport is an example but my point was that in sports, considerable care is taken to avoid death! The concept of taking your life to the (near) ultimate is natural for some and the similarity from personal experience is that sex before going off is enhanced as I may not come back....and sex on my return is enhanced as I have returned ! Risking my life, it is down to my own wits in what I do , but to have to concentrate in sex which I am sure we all get carried away in ! and also know how far I/ they should go before we end up dead is too much! I do not suggest anyone is mad , only that the concept is flawed. In the martial art example "control" is from my understanding is a major factor , in defence and attack of your opponent, to let your opponent get the advantage means he has control (which in case of domination you are not "totally" not in control provided you don't pass out ! or die!) and as said you can stop your partner if you wish, (so you are still in control but only letting your opponent "think" they are dominating you) Death is not a good opponant ! however much you trust your partner or yourself! Obviously paying such a game demands great skill and intelegence but maybe this is more to do with experience of near death and the feelings you get rather than sexually motivated feelings ..