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Lung squeeze - what now???

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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New Member
Sep 12, 2004
Hi Everybody! Im a hungarian freediver from Dahab. A week ago i dove to 35 meter 5-6 times. After coming out of the water I felt great, there were no symptoms of barotrauma at all. The following day I was entertaining myself with some corals as shallow as 10-15 meters. After coming out from the water i started to feel a strange, stinging pain in the left side of my chest. I coughed up some blood and after talking to some experienced freedivers I was assured that i had a lung squeeze.
I was hoping that the pain( slight but continous pain in my left lung, especially when walking uphill or riding a jeep in the desert) would vanish. It didnt. No more blood though, except this morning when after blowing my nose I saw some blood( very little again) in my nepkin.
Im really worried and of course angry at myself. Anyone has an idea what should I do or should I not?
Do I really have to stay out of water for weeks or even months???
Is there any medical help that could put my lung back to its shape faster?

Ferenc Veigert
I never suffered from squeeze, but my understanding is that there is usually no pain associated with it (someone please correct me if I'm wrong). Perhaps you punctured your lung somehow?

My only advice is that for christs sake seek a physician's help, especially if the symptoms persist. Don't trust some home grown advice you found in the Internet...

Your biggest concern should not be if you can be back in the water in weeks. It should be about your health and well being in general...

Edit: I did some reading and it appears I was wrong about the pain. But my advice still holds. If the symptoms persist, you really should get professional help.
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One thing I've wondered, if one did ever suffer squeeze to any degree, does it make one more succeptible to suffering squeeze again(as happens for example to people who suffer hernias)?
My wife broke her ribs and sternum over Christmas. She went in a couple of weekends ago and suffered quite a lot of pain at about 4m. Thats injury related, is that what you want to know?
I don´t really understand the term lung squeeze. It is used like it is something everyone has agreed upon what it is.

- I once pushed myself very hard to 42 meters, after that I spit blood and was really weak for three days. Lung sqeeze?
- I once got a crack in a rib - the day after that I dove to 47 meters.
I had pain in the chest for three weeks. Lung sqeeze?
- Every season If (or when) I go to fast ahead I spit traces of blood and saliva. Lung sqeeze?
- One season I started with the following 50 - 60 - 61 - 64 and within five days I reached 65. I did spit blood. I used very effective warm up techniques.
Lung sqeeze?

And when saying "spit blood" - it is not blood as pure blood. It is small traces of foaming saliva with traces of blood. I am not sure it comes from lungs it could very well come from squeezed trachea. My lungs can take a lot of squeeze but the trachea/throat is less squeezable.

I pretty much see this as part of freediving as long as strength has returned within 24 hours.

http://www.fridykning. se/freediving

"I pretty much see this as a part of freediving as long as strength has returned in 24 hours."

No! :redcard

If you were walking to the corner store and sudden coughed up blood, whether it was flecks/foam or in greater quantities, it would be a matter for serious medical attention! But because you are diving under water on one breath of air, subjecting your body to rapid pressure changes, you just figure it's part of the sport? :duh

You also say your warm up in your progression was successful. No, it wasn't. I too reached 65m last year in training and did not experience lung squeeze or spitting blood. My progress and warm-up techniques were successful, yours were not if you consider the fundamental safety of our dives. It is not safe to surface with blood in your sputum and/or coating your alveoli. Is is not safe to surface and immediately lose control of your breathing (coughing or wheezing) in a water environment.

This attitude is leading many novice and intermediate freedivers to ignore the warning signs and push themselves to greater depths before they are ready. Most of the time they are following the example of more experienced freedivers who feel it's just an unpleasant part of training, but nothing to worry about in the long run. I do believe that if you've ever suffered squeeze, your lungs are damaged and are more easily squeezed in the future. This is from my personal experience. I know have to very careful when I dive. I know that to return to my competition depth in need more than a month to safely progress to that depth after a winter of inactivity, for example. Most seasonal freedivers do too, but they are too eager to get back down to "depth."

You suppose that in one instance ou are only suffering from an inflexible trachea. No problem, right? Well, I know one person at least who ended up with a strange hernia of the trachea and had to quit diving for quite a long time. I believe he does dive again now, but cannot go below 20m.

In my books, if you make a dive and have any blood, if was a failed dive. Pure and simple.

Whether or not your symptoms fit the current definition of squeeze doesn't matter. Pain in the chest for three weeks? Bad! Being really weak for three days? (which is classic for bad lung squeeze) Bad!

In my experience, most freedivers are in denial that spitting blood is an injury. You may feel that what you've experienced is no big deal, but I can assure you from my own personal experience that it can get WAY WORSE!

Sebastien, I'd be happy to share with you my strategies about how to reduce the risk of squeeze.

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i agree with sebaztian. i did spit foaming saliva with traces of blood before. i mean months before. but this time it was different. the amount of blood was very little again but the aching pain, dizziness and weakness since weeks is very new and scary to me.
i got back to europe yesterday and consulted with a divedoctor. i told her the simptoms and she reckons its a lung squeeze.she said i have some air left in my chest since that very dive and that couses the pain. tomorrow i'll go for an x ray, then i will know more. she said if i'd have a diver insurance, a chamber would be the best solution. so far i dont have that insurance i can only inhale oxigen.
I agree 100% with laminar.
Spitting blood it´s not normal. It can be from "mild" problems as sinusitis to life-treathening diseases as pulmonary barotrauma.
There are many factors that favor pulmonary oedema: 1)Exercise 2)pulmonary hypertension 3) Contractions (excesive negative intra-pleural pressure) 4)Cold Water 5)Barometric Pressure.
All freedivers that experience that symptoms should seek for expert pulmonary consultation, specially if that symptoms are recurrent.
Freediving should be a pleasant experience, and the best signals of something going wrong, is our own body.
Motek, I don´t see any reason to use an hyperbaric chamber at this moment, in fact, the treatment of pulmonary oedema is supportive.
it would be good to stay in the chamber just for the oxigen. if it was free. but 'cos its not, i shell get a tank with oxigen.
Re: Lung squeeze -

laminar said:
If you were walking to the corner store and sudden coughed up blood,...
Well I wasn´t - I was practicing an extreme sport.

Is is not safe to surface and immediately lose control of your breathing (coughing or wheezing) in a water environment.
Takes about 10 minutes for effects to occur.

You also say your warm up in your progression was successful. No, it wasn't. I too reached 65m last year in training and did not experience lung squeeze or spitting blood.
Well I only had 7 days to perform and I was willing to pay a price. My choice.

Pain in the chest for three weeks? Bad!
Due to a cracked rib mainly. Usually takes two weeks to heal. So we are not really talking lung problems in that case.

it can get WAY WORSE!
I´ll be careful

This attitude is leading many novice and intermediate freedivers to ignore the warning signs and push themselves to greater depths before they are ready.
This is not a kindergarten - we are extreme freedivers who meet in a specialized forum to share experiences without selfcensoring or moral evaluation of our different attitudes.
(As beginner I never just copied whatever I read on an internetpage).

How hard you train is a question of attitude. A personal thing. We dont plan to get hurt - but the risks are part of the excitement for some.

I do believe that if you've ever suffered squeeze, your lungs are damaged and are more easily squeezed in the future. This is from my personal experience.
Intresting to hear your experience. Hearing this I do believe I know how to walk the line. What I am doing is not out of ignorance it is calculated risks in a safe environment of professional co divers.

Well, I know one person at least who ended up with a strange hernia of the trachea and had to quit diving for quite a long time. I believe he does dive again now, but cannot go below 20m.
Its good to hear about this examples as a warning. But I do believe that I have taken many years to slowly understand my body. Reading all examples here I think only my first 42 meter dive was what we can call a squeeze.

In my books, if you make a dive and have any blood, if was a failed dive. Pure and simple.
Well its nothing to boast about - my tougher dives - but it was all lovely dives. I surfaced with a great wellbeing very close to spiritual feelings.

Dear Sebastian,

The main point I was trying to make is to highlight the conclusions less experienced freedivers might draw from your post: ie. "hmmm, this guy says he may or may not have experienced lung squeeze, he says he has cracked a rib, coughed up blood, but only a little (not all at the same time). He went from 50-65 metres in only a few days. These symptoms and possibly lung squeeze must be normal for freedivers or at least not life threatening."

I'll accept that you may know your limits and that it is your choice to make a 15m gain in depth in 7 days, but please consider adding a disclaimer or warning when you do so for those who don't have as much experience. Deeperblue indeed has many beginners and novices who read threads like this one. Ultimately, it is their responsibility to figure out what is safe and what is dangerous, but I believe the spirit of this forum is in making important info like safety and injury prevention clear when discussing advanced techniques, even between "experts." Indeed, lung squeeze is not limited to deep divers like us, but also happens as shallow as 20m in certain cases.

We don't plan to get hurt. That's true. But if you knew that a certain method of diving would result in a lung squeeze 65% of the time, would you still do it? Would you do it if 10% of the time the lung squeeze would cause serious damage and keep you from diving for months or send you to the hospital? Unfortunately, for many freedivers, there is just not enough knowledge about squeeze and prevention to allow them to make informed decisions about their own training.

In my experience, those at greatest risk for squeeze or similar injuries are:
1. Seasonal divers who do not dive for long periods of time and then expect to be where they left off
2. Divers who only dive deep competitively and stay shallow recreationally
3. Novices who learn how to pack and can suddenly equalize more deeply
4. Freedivers who pack to go deep instead of learning how to go deep with equalizing practices and longer term adaptations
5. Novices, intermediates and advanced freedivers who are not comfortable with the depths they are attempting and so
over-pack, descend too fast, are tense, and experience strong contractions at depth.
5. Freedivers who are in a rush to achieve a certain depth before a competition and make jumps of 5-10 metres at a time

This is the simple strategy I follow to avoid squeeze and so far it has worked for me:
1. Go down slowly to allow the body to adjust to rapid changes in ambient pressure (0.60-0.75 m/s)
2. No packing (improve equalizing techniques or wait for adaptations to occur over time to allow deeper equalizing)
3. Be realistic about depth progressions and the time needed to achieve it (measured not in weeks, but months and years)
4. Employ some sort of FRC diving practice to accelerate chest flexibility and blood shunting
5. Dive only when relaxed and comfortable
6. Avoid negative pressure dives all together

I agree that in surfacing from a deep dive can result in beautiful sensations. However, in 2001, these sensations were replaced with those of fear of death by drowning in my own blood.

Safe dives,

Lung squeeze

I agree on your list of danger behaviour and types of divers who are in this "attitude of danger". Myself I did all my stupid stuff during the first eager year.

In my cultural background we are not so prone to use disclaimers. Could be we dont sue each other and our population has a general high level of education and a tradition of personal responsability (even though we see signs of adaptation to the "america way of life").
Anyhow as long as I only refer to personal experiences and dont try to STATE FACTS or urge others to copy - I do believe I can leave disclaimers out and trust my fellow freedivers to be thinking individuals.

But lets not spend time discussing this. I found very intresting claims in your text.

Does not packing - adding extra TLC - push the "squeeze depth" further down for an individual?

Is not FRC and negative dives the same thing - when it is used as warm upp technique to enhance bloodshift.


PS. "fear of drowning in my own blood" - whatever caused that state. Seems like you are the riskier diver of us two.
I have to say I totaly agree with Laminar and I thank him for writing this post because I surely would have made some stupid things on my vacation as i have the oportunity to deep dive only about a week 3-4 times a year. 2 weeks ago for the first time I did -30m and it felt realy good and with no signs of lung squize what so ever and after reading Cebaztiens post I thought great I'll be at 40m by the end of my next trip to the Sea. But i quess i'll take it a bit slower now. I sure get strong contractions in dephts that go away on the ascent.

Well I too think there should be a disclamer on ur post Cebaztian. Not all hera are so skilled and have so much "personal responsability" as U.

PS. "fear of drowning in my own blood" - whatever caused that state. Seems like you are the riskier diver of us two.

I belive there should be "were" the riskier diver.

Ur personal experiense is greatly apriciated Laminar and if I hadn't read Ur post i belive i could end the same way.
Well, definately follow Laminar's advices, 'cos you might end up like me...I think the main reason i got the squeeze it was that big jump (from 28 meters to 35) in my performance. so, definately let your body adapt depth!
Hi Sebastian,

Good points about cultural differences. Canada is not yet a country of lawsuits and punitive damages like our neighbour to the south, but we are getting there.

I wrote about my theories regarding packing as a risk factor for squeeze on our national AIDA forum:

I am certain that there are two important factors to take into consideration in lung squeeze prevention, as can be illustrated by the following example:

-Freediver A packs substantially, descends at an average speed of 1.0 m/s, lung volume is 8 Litres (extra 2 Litres of air from packing), residual volume is 1.5 Litres.
-Freediver B doesn't pack, descends at an average speed of 0.75m/s, lung volume is 6 Litres, residual volume is 1.5 Litres.

If we use, pV=K (Boyle's law) and expand to pressure (residual volume at depth) x Volume (residual volume at depth) = p (at surface) x Volume ( of lungs at surface) and plug in the numbers, we see that:
Freediver A reaches her residual volume of 1.5L at approximately 43.3m (5.3 atm) in a descent of 21.65 seconds .
Freediver B reachers her residual volume of 1.5 L at a much shallower 30m (4.0 atm) in a descent of 22.50 seconds.
Given this math (noting that Boyle's is not perfectly accurate underwater), it seems a no brainer to choose packing over no packing, if you assume that problems with squeeze occur only AFTER residual volume has been reached (this idea may be wrong, see below). To take it one step further, the ultimate application of this method would be to have a lung volume like Hubert Maier's 14L which would allow him to reach residual volume of 1.5 L at 9.3 atm or 83m. But yet he suffered a squeeze in Ibiza from a dive to 70m. Why?

Also, in the real world, it is possible that both freedivers could get squeezed in this scenarios, depending on their levels of training and pressure adaptation. But let's assume for this example, that both freediver A and B are at risk of getting squeeze at or slightly beyond their residual volume of 1.5 Litres.

So, here's the scenario that I've had some experience with in the last four years:

--> Both divers dive to just slightly more than their residual volume depth. Freediver A, packing an extra two litres, gets a lung squeeze at 45m . Freediver B, no packing, does not get squeezed at 32m. Why?

All other things being equal (impossible, I know), I believe that packing and descent speed are the most important factors during the dive itself related to squeeze, especially when developing adaptations at and beyond residual volume.

LUNG PACKING: We know that packing exerts pressure on the lungs, heart, circulatory system, alveoli, chest wall, diaphragm, etc... I remember hearing of imaging done in Kona, Hawaii of freedivers using packing. Their hearts were squashed flat by the increased pressure, apparently. When you pack, often your heart rate speeds up (heart cannot push as much blood with each stroke, so it increases stroke frequency, I think is the explanation). Also, many of us have experienced fading vision, dizziness or LMC from packing as the extra pressure in the lungs prevents blood from reaching the brain. There are also anecdotal reports of freedivers who have seen an increase in residual volume from excessive packing. Tom Sietas believes this is why he gets squeezed at any dive beyond 70m. He has a lung volume of at least 12 Litres and growing, I believe, from all his static apnea training. I don't know what his residual volume is at now. A local freediver has also seen his residual volume jump since he learned packing. He has been getting squeezes so often from shallow depths (20-25m) that his doctor recommends quitting the sport.

Now, why would Freediver A get squeezed at 45m? I can think of a couple of reasons:

If we accept that blood shift is one of the mechanisms that protects us at depth from squeeze when we dive beyond our residual volume (otherwise we'd be toast!), then increasing the air pressure within the lungs with packing could inhibit blood shift toward the lungs in some way. If packing can cause LMC, blackouts and a squashed heart at sea level, then I think it is safe to assume that if will have some effect on blood shift you as you descend.

The most drastic change in lung volume is in the first 20m of the descent when you go from a full lung volume to one third that volume. For Freediver A, she does it in approx 10 seconds! As far as I know there are no specific studies on the rate of blood shift vs. lung volume, but I would guess that your circulatory system requires some time to adjust to the pressure change. For example, if any of us descended to 30m in 1 second, a squeeze would be highly likely. This is why negative pressure dives can be so dangerous. Exhale and drop and suddenly in a few seconds you are at 100m of pressure!
I also wonder also if the extra pressure in the lungs from packing does not drive away plasma from where it is needed, meaning that the body requires even more time to redirect it to the core. But in the time it takes to react to the ambient pressure change, Freediver A is already at 25m and still going down and a negative pressure inside the lungs does not get equalized safely.

This idea implies that squeeze doesn't actually happen at residual volume. It is "set up" in the first 20m and going deeper than that just nails the coffin shut, so to speak. When you reach your residual volume, your blood shunt has not had time to come into full effect and thus squeeze ensues.

In addition to the delayed blood shunt caused by packing pressure in the lungs, I also believe that a rapid descent means that the ambient pressure increases too quickly for the blood shunt. If Freediver B, not packing, descended at 1.2 m/s, I would be afraid that she would also suffer a squeeze by not giving her body enough time to shunt blood to the core.
Also, packing can result in extra speed on the descent for inexperienced divers, as they struggle to overcome the extra buoyancy created by their over-inflated lungs.

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I think the reason so many freedivers put themselves at risk of squeeze is because lung packing and a rapid descent seem like solutions to simple problems: equalizing and fear.

Most new freedivers start to run out of equalizing air at around 25-30m. If they switch to Frenzel they might make it to 35m -40m. Doing Frenzel deeper than 40m requires either the mouthfill technique or excellent chest flexibility, which in turn requires much more diving experience than a novice would have.

Packing an extra litre or two immediately provides more air for all equalizing techniques. Suddenly, 45m-50m is not impossible at all, even with a crappy equalizing technique. It is common for freedivers to progress from 30-45m very quickly. Ten metres jumps in depth in a weekend are not unheard of. But often squeeze happens as well.

Excessive descent speed reflects the fear a freediver has with a new depth or pb. If she were completely comfortable, Freediver A would realize that there's no rush and that a slower, relaxed descent is more efficient. But often the impulse is to make the depth as fast as possible and get the hell back to the surface! At my first nationals in 2001, I sprinted to 46m and suffered a moderate squeeze (coughing blood, wheezing). The dive, if I remember correctly was probably around 1'20" or less. Now it takes me over 1'30" to reach 60m on the descent alone and no squeeze.

Diving deep without packing is possible. All it takes is more time to adapt and equalizing skill. (Umberto Pelizzari dove over 80m without packing.)

Okay, Sebastian, I'll try to address how negative pressure dives and FRC dives are not the same for training chest flexibility.

1. The goal in my mind for helping your body adapt is to simulate in training as close as possible what actually happens to you on a dive. If my goal is to dive in a way where I allow enough time and create a gradual and adequate stimulus for blood shunt and peripheral vasoconstriction, then it is obvious to me that a negative pressure dive (full exhale), is not appropriate. I am also talking about negatives in the way that most people do them: between 5-10 metres, free immersion or sink down, hang for some time, then come up. Depth of course depends on your interpretation of a "full exhale!" :) So, if I do a negative pressure dive, I go from 1 atm of simulated pressure to over 8-9 atm in only 10-20 seconds. This is not what happens in an inhale dive, not even at any point in the dive. And furthermore, I don't think it promotes blood shift in the right way. Think about it: in a negative pressure dive, you reach the limit depth and wait until your body reacts instead of having your body react as you go down, thus preventing injury. For me, the final proof that negatives are not the best technique for everyone is that I know of several people who have used them (including myself) and have done them quite deep, and yet still get squeezed.

Not only that, but I've always felt that negative pressure dives are not as good for stimulating an increase in water pressure on the whole body's core. Sure the lung volume is reduced considerably but the rest of the body is still only at 1.5-2.0 atm. Plus, if a freediver starts of with 2-3 negatives while he's still hot and dry in his suit, I doubt there would be much stimulus for vasoconstriction (constrast this with a no-suit dive). Again, specificity is key.

2. On a properly done FRC dive with extrememly slow ascent (sink from the surface) and single mouthfill equalizing, I believe the phase between 20-25m and 40-45m is easily and gently simulated up to 20m of depth. I have done FRC dives much deeper but have found repeated dives to 20-25m to be enough. The key is time and stimulus for blood shunt. When I say sink from the surface, I mean that literally. You should sink like a dead body, you might even sink ass first, and it could take 30 seconds just to reach 10m of depth. But this is extremely important for giving your body adequate time for full blood shunt and vasoconstriction. Repeated 6 - 7 times in a session (warmth allowing) and a little as twice a week makes an amazing difference in chest flexibility. But, the effects are far more USEFUL if you also modify you inhale diving style to match your training. So don't do this exercise and then pack 3 litres and sprint to depth. You might still get squeezed.
As I said above, my average speed for a descent is approximately 0.65 m/s but in the first 20m it is more like 0.50 m/s.

Am I the riskier diver of us two? Well, neither of us know about the risks we currently take in freediving, except I know that you jumped from 50m - 65m in seven days, something that I would never be able to do without injury after several months off. That's too risky for me!

My squeezes were in 2001 and 2002. I have not suffered one since that time. Please keep in mind that when I had my squeezes in 2001, no one knew how to avoid it, and none of the local freedivers, not even the world record trainers in town had any useful advice for avoiding it or reducing the risk. I contacted the diving experts like Dr. Claes Lundgren and he didn't have any advice about prevention. So while the squeezes were still only moderate in severity, perhaps like you've experienced, I tried everything, including negatives and a progressive and tiring warm-up sequence, but it kept happening from time to time.

Then came my wake-up call, a dive to 42m without fins in 2002 that resulted in a squeeze that profoundly scared me. 42m was shallow for me at the time. The squeeze shouldn't have happened, but it did and it was horrible. Is it being risky to make a dive when you don't even know what the consequences are? If I had know that diving while congested and cold with a rapid descent would almost certainly result in a lung injury I would not have done it.

This is my motivation for sharing and discussing this information. If someone has a squeeze and doesn't know why, I feel that perhaps they can benefit from my unpleasant experiences and avoid them in the future, and hopefully avoid something more serious like I had. Luckily, I can still enjoy freediving. But I wonder how many others cannot.

Hope these explanations help.

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I am not sure it comes from lungs it could very well come from squeezed trachea. My lungs can take a lot of squeeze but the trachea/throat is less squeezable.

Kirk Krack and Martin Stepanek talked about this in the two clinics I attended. They both felt that ruptures in the trachea that caused blood to drip down into the lungs was the most likely caused of what doctors and divers call lung squeeze. Seems like Kirk said the doctor takes an x-ray and sees blood in the lungs and automatically says “lung squeeze”. The argument was just like Sebastian said. The lungs are very flexible and not prone to damage from squeeze, but the trachea is not. They had some good thoughts and info to support the theory, but admitted it was just a theory.

This theory also supports the thought that damage increases the chance of damage in the future. The lungs are known for their ability to heal where the trachea is probably not.
Hi donmoore,

Ttrachea squeeze is indeed a possibility.

But even if severe lung distress symtoms are experienced (coughing blood, wheezing, difficulty breathing, reduced Sa02, weakness, dizziness, etc) as a result of a trachea squeeze, then the end result is still the same. If it is correct that the trachea is less flexible and adaptable to pressure than the lungs, then that's even more reason to be careful and give the body TIME to adapt to pressure changes. Also, if it is indeed a trachea problem, as you say, it's more likely that long term damage could be suffered.

I suppose there is no way to tell immediately after a squeeze whether or not it is the trachea or the lungs. A scoping of the trachea by a doctor would reveal whether or not there was any bleeding. If anyone seeks medical attention after a squeeze, this would be a good thing to have checked out.