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Coughing up blood

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New Member
Jun 23, 2003
I went freediving last weekend and coughed up blood after a 26m dive. I proceeded to cough up small amounts of blood for about half an hour afterwards. Quite worrying! I obviously stopped diving for the day. This is well within my limits and was preceeded by 4 graudually incresing dives. All of the dives felt very comfortable until the ascent on the 26 m dive when became aware of a gurgling sensation in my windpipe - blood - not good.

The dive was on full lungs (but no packing) so I doubt that my residual voulme would have been reached. It seems likely to me that the problem might pulmonary barotrauma as discussed in Eriks article "The Risks of Ascent". I have also heard that it is possible to damage your windpipe by extension of the neck under pressure?

Just wondering if anyone has had similar experinces or can provide any advice. I have been reading the articles by Peter Scott and Erik Seedhouse on DB which are helpful and been to see a GP who sent me for an xray but was otherwise baffled.
hi Matt,
that doesnt sound too good. first piece of advice i would offer is to lay off diving for a good few weeks... unless someone else knows better, you should think about a rest period of at least 3 weeks.
if you have a normal lung capacity and residual volume, then i wouldnt expect you to be at residual at 26m. then again, you could be getting close to your residual volume. depending on how you took your last breath, you may not have inhaled as much air as you thought - ie. you didnt inhale your true VC. this is more likely if you were wearing a thick suit and/or took your last breath when vertical in the water... with your lungs submerged.
one thing i wonder about is how you equalise.... i think this may be an important factor. do you use valsalva or frenzel? with valsalva the effort comes from the chest and abdomen. these movements may have created excessive negative pressures in your lungs. another posibility is that you had forceful 'CO2 contractions' during the deepest part of the dive.
if you think these things may have contributed then the answer is to learn the frenzel method (see EricFs tutorial) and develop a higher tolerance to CO2 and relax more during the dive. ... you should try doing these things anyway! :)
that's about as much help as i can give right now.
i think Pete could offer some better input here.
ps: i used to live in Swansea from '95-'99... :) lived in Sketty, Uplands, Brynmill and Mumbles for a while. i learned to swim in the Swansea leisure centre pool... i still remember desperately struggling to cross that 33m pool! :(
Hi Alun

Thanks for the advice.

The stuff about equalizing makes particular sense. I do tend to be quite 'enthusiastic' with equalizing due to a fear of ear damage. I can see how this would create excess -ve pressure in the lungs. I use the Valsalva technique but have been trying the Frenzel recently and plan to start using this. (After a little rest)!

I did not experience any CO2 contractions during the dive so have ruled this out.

Swansea is a great place I have lived here for about 8 years - now living in Brynmill. There are a few freedivers and spearos around who go out on the Gower or West Wales when conditions are right. I swim in that same pool although the new 50m pool is really good. Not sure if they allow monofins in though?


well, that could be what's causing your problem...
i've seen it happen to other people who use valsalva.

try working through Eric's document - to be found on www.ericfattah.com. the good thing is that you can practice it dry without fear of it affecting your lungs. some people have a really hard time learning it - but practice, practice and more practice is the answer. there are a few advanced variations of the frenzel too. the most important one - the mouthfill - is covered in Eric's tutorial.

Swansea must be a good place to live as a freediver, with access to the Gower and the NDC. i also used use the university pool a lot when i eventually got into lifeguarding. back then it was an old 30yard pool. i left Swansea before they built the new 50m pool.

Hi Alun!

say, what more advance frenzel varations are they? i'm curious, although it works fine for me now.

Hi Matt,
For your dive profile I don't think that was a lung squezze. Did you made negative dives as warming?. Was your equalizing forcefull?.
When spitting blood there are 2 posibilities: Upper or Lower respiratory tract.
That's why is good to have a physical examination of ENT and thorax.
It's wise to stop freediving until you know the cause of it.
Hi matt
I think Alun may be right about your equalising. I didn't say anything on the day but I watched one of your first dives and thought you were making more bubbles than most.. maybe you are losing volume with your equalising.

Let me know if you find out any more and hope it is better in time for the next one.
hi Deep Thought,

well, i dont think they're covered in Eric's tutorial - last time i read it anyway. they dont allow you to equalise any deeper than Eric's standard mouthfill frenzel - but they can help to make the process a little easier.

1. continuous pressure. instead of allowing the pressure to build and then going pop, pop, pop by doing frenzel. you apply continuous gentle pressure with your tongue, which keeps your ear drums in the normal position (ideally) or slightly bulging outwards. (be careful not to apply too much pressure though.)
the nice thing about this method is that it puts less strain on your ears, which is a good thing in the longer term - less chance of developing tinnitus over the years. the nice thing about it is that you dont hear any strange sounds or even feel any pressure! it's as if you're not equalising at all. you can do it all the way from the surface if you want, but you'll probably have to top-up the air in your mouth a couple of times.

2. combine the continuous frenzel with other actions such as a 'jaw thrust' or BTV, which are similar things essentially. this is probably only needed if your ears are farily tight, like mine. i'm not sure if these 'combination methods' have names - they may have. it just helps the air get into your tubes, so it requires less pressure to equalise.

it's easy enough to practice these dry too.

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Thanks to everyone who has responded. I have been quite worried about his over the last couple of days but feel better about it now. I've experienced a slight discomfort in my throat since although it is much better today. I have just been out on my mountain bike and feel fine:) Going back to my GP on Friday to get checked out.

Fpernett, you mention getting a physical examination of the ENT and thorax. What is ENT? Ear Nose Throat? I did no negative pressure dives to warm up and think this might have been a contributing factor. It was my first time in deep water for a couple of months and I think I was a bit too keen. Must spend more time stretching and warming up. My equalizing is definately forceful but I will be trying to change this.

I agree that it was almost certainly not a lung squeeze, as described in Peter Scott's article which is a releif 'cos it sounds horrendous!
Always had the same problem. never any pain, but a small amount of blood in the back of my throat when i cleared my throat & spat it out after a period of diving. doesnt matter if it was a series of shallow dives or deeper (20m plus ), i get a smalll amount of blood in a phlem like goo. never stopped me from diving though.
combine the continuous frenzel with other actions such as a 'jaw thrust' or BTV

10x Alun, never heard/thought about that one before, maybe it'll help me to develop the BTV with some practice.
anyway, i was asking from curiousity, i never had any eq. problems that were'nt of my own fault.
(hood squeeze being the most memorable reason:waterwork)
Matt do you breathe out slightly through your nose as you descend? Might it be your sinuses? Sinuses sometimes leak blood
for short periods of time under stress. Like a bloody nose without
the nose being involved.
Do not assume anything


I too have this problem at relatively shallow depths well above my residual volume (in and around 20-25m) and continued diving has resulted in cumulative damage that is not healing over time.

In my case it is in the lower throat and the blood is a result of ruptured blood vessels due to what seems to be a 'herniating' thoracic airway. After much discussion with some of the foremost Freediving researchers in this area I have concluded that, in my particular case, I am at great risk until the damage can be properly healed or repaired.

This was proven to me just three days ago when, after ten months of not diving- what I thought was taking time to heal from a very major 'squeeze', I once again experienced a fair amount of blood after performing a safety dive during Tom Lightfoot's dramatic recovery (see my reports from last weekends Canadian Nationals).

A stretched neck (from looking ahead), improper warm ups, negative pressure and poor flexibility are all factors but may or may not be the only considerations.

The only way to be sure if my diving days are over is to get a tracheaoscopy, a scope sent down the airway to look around, which I will hopefully have done soon. No doubt the results of the test will be helpful for anyone who has suffered from this problem or may have a disposition for it as I seem to.

In the meantime please take caution against any further aggrevation of this condition. I would hate for anyone to have to go through what I did the last time this happened to me- major edema, symptoms and risk of secondary drowning, brusied muscles and shortness of breath for three weeks- it was that bad.

Perry Gladstone
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Ive ruled out the sinuses in my particular case as the blood was definately coming from the throat or lower down.

I am thinking that a tracheaoscopy would be a very good idea. I too suspect I have a disposition for this having experienced it twice before to a much lesser degree. My current thoughts are that the problem can be avoided with a proper and gradual warm up to include streatiching of the throat although I would like this to be confirmed by a doctor. In my case there seems to be a 'threshold' depth of around 25m. If I can complete warm up dives to this depth in comfort I seem to be ok to proceed deeper without the problem occuring.

Im still seeking further medical advice and giving the matter a lot of thought and will post any findings as I get them.



Kirk and I both had this problem about a month ago -- he was just coming off of a cold after the Cypress competition, and I was (apparently) just starting to get one. For both of us it was a bit of a trachya squeeze. He was out diving the next day and has been since, while I haven't been in the water since due to this cold. The symptoms were gone by the next day, although I would take it easy for a couple of days.

One thing I did notice during the dive to 24.8m when it happened (it happened to Kirk much deeper :D) was that I hadn't closed by glotis well enough and as the pressure shifted I had a couple of "pulses" through my through where it felt like it was sucking air in or out but not under concious control. I haven't experienced that before and thought it was a little odd... and concerning at the surface when I spat up some red stuff. :) Kirk said just take it easy for a couple of days and it should clear up. Things seem to be fine now.
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