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Thread Status: Hello , There was no answer in this thread for more than 60 days.
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New Member
Oct 3, 2002
In other words: spitting blood after deep breath-hold diving.

It happened to me the first time I dived down to a shallow 25 m.

Hello, have any of you experienced this condition in your deep dives 40+?

Regards, gerard.
Yep. I've been there also!

For me it also started at about 25m. The first time I got this, I stopped diving immediately for that day. It appeared again soon and now I spit blood every summer for time to time. Not much, but it's blood anyway. I'm not sure if it's coming from my lungs or throat. First it starts to tingle in my throat and then starts couching and spitting little blood, not much but anyway.

I have been talking to many people about this subject and many of them think, that it's something normal and it will not kill you (even though some say that it's very dangerous because it can cause secondary drowning). I've noticed also, that when having hard time to equalize, spitting blood occurs more often.

I heard a theory that the blood is coming through your "alveoli" because of negative pressure in lungs. This is because you are not strech enough. At first I was affraid about this thing, but I kept diving the same way and stretching more often also. Suddenly I noticed, that I can go deeper and deeper and no bleeding. I think my body had adapted to go deeper and diaphragm had became more strech (which is very important).

I think I will spit little blood when going to open water again after winter, but I'm sure it will also stop at some point.


Thanks for your reply. It's nice to see suomi apneists around:)

Yeap, this happened to me 6 years ago when I was only a lay snorkeler. I stretch a lot now, so I guess i should be alright. But i asked this question just in case.

BTW where in Finland are you located.

Regards, gerard.

If couhgung blood comes from negative presure on loungs in your case gerard at 25m how come nobody couchts blood in no limits dive (i have't heard of it jet)? I konw about blood shift and all but isn't this the same thing?


I'm located in southern part of Suomi at "city" called Lohja. So you can speak at least one word in finish, here we go, few more words, lesson 1 ;)

beautiful woman=kaunis nainen

Stop, end of finish for now... You can do everything you need with these words.

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Haemoptysis is a serious sign and should not be taken lightly. Whatever the reason, it cannot be ignored especially at those shallow depths. It means some airspace does not equalize properly and draws blood through negative pressure. I would strongly suggest to have it checked by a professional or at least ask the advice of some expert. Dismissing the issue just because "it's not much blood" can be very dangerous.

Not normal

I have to agree with Hydro.
That is not normal, the blood can come from upper respiratory ways (like sinuses) or from Lower respiratory tract.
In the last, I think are several factors mainly the negative intrathoracic pressure. You can develop extremely low pressures by empty lung dives, really deep dives, contractions.
It's important to be evaluated, to rule out anatomical pulmonary problems or ENT diseases.
Done that allready!

My friend has also this same problem, and he went to a specialist. He is usually spitting lots of more blood than I am. Ok, he went to a specialist and first they took regular x-ray pictures. Doctor saw nothing and became interested. Next they took magnetic x-ray (or whatever it's called). Doc said that if you are spitting blood, you have to have some scars somewhere, and magnetic picture reveals them. Result was, nothing found. Not even slightest scar or anything to mention about.

Last test was brochoscopy (where a little camera is used inside your thorax). They took some pictures from his throat, and there were some vains near the surface of the throat.

Docs final opinion was that where ever the blood is coming, it haven't broke anything. He also though that the blood might come from those vains at his throat or maybe from the sinus. But doc said that his lungs were just fine.

This is a complex issue

that is curently being researched by a Swedish physiologist. I guess there will be others doing the same thing.

Let's wait for the final result.

Regards, gerard.
I had this last year after a dive, coughing blood for about an hour after a dive to about 35m. It was in Nice and I was diving alongside one of the guys who works there. He said it was because my head and neck were very unrelaxed during the dive and this makes can cause some blood vessels around the trachea to break. He was convinced the blood was not from my lungs - as was I as it didn't feel like it was coming that far.
Anyway now I do a lot more neck and shoulder stretching, think more about my head and neck position and it hasnt happened again...
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