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lung squeeze

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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New Member
Jun 25, 2004
i might bore you with my problem and i know that it is already discussed but i need some opinions.
i spit blood my first time when i did 37 meters( pb was 32 before)
i was really shor on breath as well.
the next time i was spitting blood was when i did 50 meters (pb was 45 before).
last week i was diving again down to 37 meters after an empty lung dive , a worm up to 18m and an other worm up to 32m. the result was a new bloodspit, but really little.
when i was diving two days ago i went to 35m for 3 times and then to 42 meters. i was spitting blood again.
does anybody know how long the alveols need to recorver????(i ve heard that they are really fast to recover)
is it possible to get permanent lung damage?
what would you recommend to do or to train???
tom sietas told me to stay out of the water for a year.
is there another possibilty?? i really wanna dive.
thanks alot for answering andy
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Well, that kinda sux! Umm... I dont know about how lungs heal in relation to freediving, but I do know about smoking. Take for instance a person who has smoked for X amount of time. If that person quits, the lungs generally heal quickly. I dont know a specific time frame, but I do know it is fairly quick. I want to say like 6 weeks, but I am not sure. I will find out though. You might want to go see a doctor though. Diving is awesome and all, but you could be doind really bad damage. I dunno, I am not a doctor, I'm an avaition electrician. Way different jobs. I will defenitley ask and find out. BUt I think your best bet is to see a doctor.

Good luck, let me know what you find out!!
Read the article by Peter Scott if you haven't already on Lung Squeeze intitled "Fear the Squeeze." It's excellent, and also explains alot of the very real dangers of lung squeeze which in extreme cases could certainly cause death. It could also keep you from diving deep for life, as has been the case for at least one international level competitior here in Canada.

The article is here and has helped me greatly since my first squeeze.

Safe dives, and take this seriously!

All the best,
And keep in mind that not all traces of blood are necessarily from the alveoli/lungs. Does your throat ever get stiff/sore? There is the possibility of blood capillaries in the throat, or higher, bursting as the air spaces collapse or come under stress. Also I find I incur small traces of blood on very shallow dives when I do many dives in a row with short intervals, or am more exhausted than usual. This may have to do with hydration and/or tension.

Another thing to keep in mind, is that the dive that finally caused the blood, within a dive session, may not have been the last dive you did before noticing the blood. Depending on the amount of squeeze, or the source of the blood leek, you may not notice anything different until the blood makes its way deeper into the throat or lungs. This has happened a couple times to me. So far it seems to usually be blood not from the lungs, although I have had two dives where I believe it was from the lungs.

Just info of my experiences.


I believe it was Eric F who said that any fluid from the lungs would be more clear and viscuous. He also said that breathing would be very difficult. I spit blood sometimes, but I am almost positive it is coming from my throat. My breathing is not affected at all and there is no pain. The urge to spit itself is very minor and feels just like any other collection of mucus in the back of the throat. After one or two "spits" the blood is no longer there. Although it was pretty freaky the first few times it happened, now its no big deal.
I've seen a few people go through this and most of the time it turns out to be blood from the throat, not the lungs.

I had one bad one, in Cyprus last year, where it was just about definitely from the lungs - bright orange frothy blood and difficulty breathing for a few days.

I took it easy for about a month afterwards and later that summer after another accident (a scuba bend) I ended up having all my lung function tests and an X ray on my lungs done - two months after Cyprus there was no sign that a specialist diving doc could see of damage to the lungs - which is reassuring!

but I'd still recommend you see a doc, esp if you still have trouble breathing

I have spit blood that is coming from my sinuses and only once spit blood from my throat/lungs.

I've been doing a stretch for a while now that I have found really relaxes and loosens up my throat quite well.

Take a breath and hold it. Then clench your hands behind your back and stretch them up and out behind you while sticking your chest out and bending your head back. This is a pretty common stretch, but this next bit really helps. Most people who do this stretch end up shrugging their shoulders. Instead, while stretched out with your head back, try to relax your shoulders and drop them down. By doing this you'll find you get a great stretch throghout the throat area. The larger the breath, the more stretch you'll get. Just be careful not to pack too much and take it slowly.

I used to get a twitching almost like contractions in my throat when I got close to my pb depths. Since starting to do this stretch I've had no more throat problems and I think it's also helped me to equalize more easily.

Ok I know that this is a long post, especially since it is my first but please bear with me I do have some questions I would like to ask.

Firstly I would just like to say Peter Scott has put a comendable amount of work into researching barotrauma of descent as shown in his article "Fear the Squeeze".
I hope he receives continuing support from both the medical and diving communities in researching a very important aspect of this sport.

Being a rookie diver, I have not received formal instruction and was previously unaware of the frequency with which this condition occurs. I knew about the danger of squeezes associated with negative dives ie.
"If the diver descends with the lungs empty or nearly empty they can be compressed below residual volume in as little as two meters of water. Compression below residual volume causes the pulmonary capillaries to swell, filling the reduced volume slowly by leaking fluid into the lungs, if the squeeze is significant fluid can accumulate in the alveoli."(Richardson. A. et al. The Encylopedia of Recreational Diving, PADI).

Are the divers experiencing this condition reaching their residual volumes? and is this what is causing the problem?

I don't know if any of the divers reporting this condition had been performing No Limits dives but one thing I gleaned from Peter Scott's article was that a possible cause of the barotrauma was going too deep to fast. Did he mean that greater depths were being reached by these divers without carefully progressing or that the descent rate was too rapid? Wouldn't that mean that No Limits divers are constantly at risk as their descent rates are rapid?

I recently saw a doco on Yasmin Dalkilic's record No Limits dive, during which she gave a commentary stating that when she reaches a certain depth (I forget how deep it was) that her lungs no longer have air in them and fill with plasma (blood?) which she then forces up into her sinuses so that she doesn' t have to equalise any more. What is with that? According to Peter Scott she is definitley courting pulmonary edema, intra-thoracic hemorrhaging and hemoptysis??

Thanks for bearing with me, any answers would be appreciated.

Greetings from Downunder!:D
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What Yasmin probably means is that when she reaches a certain depth she floods her sinuses with water she is diving in and then no longer needs to eq. When she finishes the dive the water drains out. Many divers who go very deep use a sinus flood. Do a search. I know a number of threads discuss this advanced technique.
Even at 70m she would still have 1/7 of the air she started
with and if she packed she could have 1/5 of a normal
breath, so with the air she needs to equalize she would still
have more air than at the surface before a negative without reverse packing.
While we're on the topic of lungsqueeze, I'd like to know what kind of symptoms those of you who have been squeezed have experienced.

I got squeezed for my second time last night, and I knew exactly when it happened. I had just turned and started pulling up on a warm up dive to 28m, and when I tried to recover a bit of air from my mask, I accidently inhaled as opposed to sucking the air into my mouth. (using my chest to inhale) As soon as I did it I felt the pressure on my chest and knew I had likely squeezed myself. I surfaced and could feel the congestion in my lungs immediately, and although there was no coughing, several minutes later I started to spit blood. I continued floating around the line and watch my buddy doing some pulldowns to 15m, and 30 min later it had cleared up completely and I only had a vauge post-pressure feeling in my chest.

Today I feel completely normal, however I think I'm going to avoid any diving for a couple weeks, and any deep diving for about 6 weeks or so.

Another question to those of you doing deep enough dives that fluid (plasma) is still in your lungs upon surfacing. What are the symptoms of that? I remember hearing Mandy say that she would feel congestion, but do you spit anything up? Is it clear or pink as opposed to red?

I've been streching extensively before my dives since my last squeeze, concentrating on my diaphram streches... except for last night's dive. I've had deeper dives with no trouble whatsoever, and reverse packing dives to 7-8m also with no trouble. So I'm putting even more stock in the streching before diving, and as Peter Scott has done, I'm going to implement a daily streching regimen.

Looking forward to more imput.
Pete has mentioned that both points, rate of increasing PB depth and rate of descent, are factors in creating conditions for lung squeeze. If you push beyond what you are flexible enough to handle - lung squeeze. If you descend too quickly, especially from the surface, then he theorizes that the blood is shifted away from the alveoli, and enough may not have time to shift back when needed to fill air space in the lungs, so greater pressure builds up due to more air space compressing.

I think the majority of people are having lung squeeze while doing constant ballast dives, as opposed to no-limits, if only because people more often take part in constant ballast. Also with constant ballast there is more movement and muscle forces that would oppose the vacuum effects occuring in the lungs, which would heighten the chance of lung squeeze. Case in point: a fellow would get squeezed almost every time he dove past 20m, yet if he did a free immersion, there was no problem. Not necessarily that free immersion generally applies less stress around the lungs, but in his case these differences in movement and technique (his being unrefined for both) were all that were required to have a different effect on his body.

Lung squeeze, is often happening when divers are passing residual lung volume depths (30-50m), which many do pass. However, I theorize that lung squeeze can occur at any depth where your muscles used in opening the lungs, are free to contract. That means if you take a full inhale and go down to 10m, then you will have halved your lung volume, which means you could attempt to contract the muscles again which can enact a force opposing the continued compression as you descend. Resisting the compression I think could cause similar conditions as having a negative lung volume, thereby setting the conditions for squeeze.

I as well believe that contractions can be the cause of lung squeeze or be an strong influence on the conditions. I theorize that contractions while descending, especially prior to reaching one's residual lung volume depth, set the conditions for lung squeeze. It may only occur for those who are a little, or a lot, more sensitive to lung squeeze than the average freediver, but nonetheless, I believe it is an important factor towards understanding the overall cases.

I believe, my lung squeeze experiences so far have both been due to tension at depth, caused by too much awkward motions in reversing direction and maintaining position. That of course being on top of reaching new PB depths. One case I had congestion and sickness previously, so I was probably stiff in the muscles from this. The other time, I had felt stiffness in my stomach prior to the dive. So I guess what I am suggesting, is there are many factors which probably came in to effect for those cases but some unnecessarily had more effect than others.


lung squeeze symptoms

My first lung squeeze, I experienced blood spitting, starting with frothy pink and a few times later, about a half teaspoon full of bright blood. However, I only noticed when I let out a large exhale and heard a raspy-bubbly sound at the tail end of the exhale. I proceeded to forcefully exhale as much as I could and repeated hearing this. This after a few times, induced a tickle, and initiated the need to cough. I did not feel the need to cough further once I stopped exhaling so much. This became shallow breathing and a slight shortness of breath. I did not experience any sensations beyond these and especially no physical strain/pains on my muscles and body.

The second one, I felt the need to cough shortly after surfacing. My body felt fine. I immediately began coughing up various amounts of blood from slight little pellets of blood to half-full teaspoons worth. Breathing was definately short and I found I eventually could not perform physical labour very effectively and required to rest almost immediately after I did something, such as pulling up a weighted line.

Later, after the blood stopped and I could inhale fully, I found my shoulder to be sore on deep inhales and certain movements. It also began jabbing with pain every now and then. A couple days later while massaging my should I found it to be localized and found out it was a torn trapezius, but a quite small local area of the muscle. It has been almost a month and the shoulder muscle has just recently healed almost completely. As well the following day of the dive, I began experiencing stiffness all over my torso, around the ribs and chest.


Lung squeeze effects on me included shortness of breath, rhaspy sounds towards the end of my exhales and blood mixed with phlegm when I spit. I also found that my intercostal muscles were sore the next day.

Every time I have squeezed myself, or felt as if I was getting close to a squeeze, I think it was because I wan't relaxed enough. I'm quite religious about my stretching so I'm confident it wasn't due to that. If you get anxious about your dive and don't relax throughout it, you're inevitably going to tense up and run the risk of a squeeze.

Aaron, sorry to hear it happened again. Are you planning to take the advanced PFD workshop here in Ottawa in the fall? I expect Kirk will be covering more about the dangers, causes and wasy to avoid getting squeezed.

I have coughed up blood after several dives now the most recent occasion being in Cyprus this year, just before the competition. As there were so many freedivers around I was able to gather quite a bit of information and advice on the matter. These are some of the top tips I recieved (thanks to everyone who helped)on how to avoid lung squeeze or damage to the trachea resulting in the rupture of blood vessels (not in order of importance):

1. FLEXIBILITY not just muscular but of the lungs and rib cage (intercostal muscles?). Upper body stretching with full and empty lungs. This can be done with packing and reverse packing on the exhale stretches although I think it would be wise to build this up slowly.

2.WARM UP. A lot of divers recommended long hangs at quite shallow depths (10-15m) to become relaxed and comfortable.

3. DONT LOOK UP OR DOWN. Stretching of the trachea can put stress on blood vessels near the surface and cause them to rupture so it is important ot resist the urge to look for the bottom/surface/tag.

I was not allowed to dive in the competition as the doctor recommended a long but unspecified recovery time. I felt fine the next day and did some dives to around 20m with no problems at all. Im currently undecided whether I will continue to try deep dives. I am quite happy spearfishing in relativly shallow water at the moment but might try some deeper dives in a couple of months time. If i do this i will be doing a lot of stretching and building up the depths very slowly. I have no medical reason for saying 2 months recovery it just seems like a sensible time to me based on what the people I spoke to said.

I think that for some reason I am more susceptable than most to lung squeeze (or trachea damage) - probably a lack of chest/lung flexibility but I also wonder if some people just happen to have blood vessels nearer to the surface in pressure sensitive areas?

My first lung squeeze occured quite a few years ago when as a complete novice I forced my way to a depth I was not ready for. I also wonder if the damage caused then made me more susceptable to future damage?

I hope you are able to dive again soon.


i've had a few minor lung squeezes during the last year. my symptoms also include wheeziness on the exhale. this seems to be a common symptom and must be caused by some fluid in the lungs. i believe that the worse the squeeze the sooner you'll hear the wheezing on the exhale. in other words, after a very minor squeeze you'll need to exhale fully before you hear the wheezing. i've never had shortness of breath etc but have felt just a slight tightness in the chest for the subsequent 24 hours.

personally i've never felt an urge to cough, but i gently cough anyway just to check what comes up. when it happens it's usually just a few small traces of red in my spit. a couple of times i've had some larger red spots in my spit (but fortunately i've never spat any measurable amount of pure red blood... if you see what i mean.) i've never seen anything pink or frothy - usually translucent red, and maybe some yellowy/orange phlegmy goo in my spit.

personally, i'm fairly sure my squeezes are caused by contractions on the descent. these are usually gentle flutters which start around 30m and can continue until i reach the bottom. these contractions are produced by my intercostals tensing as if to inhale. i have done dives with contractions on the descent which didn't result in any squeeze, so i'm not certain if it's fair to only blame the contractions. none of my buddies don't get them. i think the reason i get them is because i've long since stopped doing any apnea training (statics / dynamics etc) and never do any CO2 tolerance exercises. i think my CO2 tolerance has slipped as a consequence. (i stopped doing them because i have very little spare time for such things and i genuinely don't really believe it's necessary - at least not at the level i dive - and probably much deeper - you can rely on adaptation and technique - but that's another story)

i'm now starting to think it may be a good idea to do CO2 tolerance exercises purely to avoid having contractions. so i'm now trying to make time to do some training. i will also do some dry hypercapnic statics (1 breath, hold etc etc) shortly before diving. i hope this will have the greatest effect in supressing my urge to breathe during the dive. i also intend to do some stretching (again, another thing i rarely bother doing) and perhaps do some uddiyana bandhas. i could probably mentally block the contractions, but the problem is that during the descent i tend to concentrate on equalisation and i think it may be difficult for my feeble brain to do both of those tasks simultaeously, espcially with background narcosis.

i should mention that my 'breathe up' is very slow and so i tend to take down a lot of CO2. i also have a tendency of breathing up slower and slower the deeper i go... which may not be a bad thing in itself.

the first time i ever saw any blood in my spit was in 2001 when i first broke 50m. i remember being very concerned despite the fact that i only saw about 2-3 ant sized specks (i.e. next to nothing!). i now realise that this wasn't a lung squeeze but the result of some damage to capillaries in the upper throat, probably near the glottis, and was caused by ineffective, forced equalisation.

here is my advice....
1. do all you can to avoid having contractions at depth, but don't achieve this by hyperventialting! this is probably the most important thing
2. if you start to struggle to equalise on descent and become tense, then turn around. equalisation should feel effortless. this is probably the second most important thing.
3. not sure if diving speed is such a big factor, but if you pack a lot then it may be a good idea to dive slower to allow extra time for blood to return to the core.
4. increase your PBs at a sensible rate
5. do some stretching.

just remembered another possible factor which could contribute... holding onto the air until you hit the surface after packing a lot. if you do that your lungs will inflate from 100% to 120%+ in just 2 secs. that sudden expansion beyond TLV could be quite stressful. i try to exhale a little in the last 2m.

.... there, i think that about covers it for me. :)
Hi everyone,

I'm on vacation in Ontario--beautiful Georgian Bay (windy!:D ). Thanks for the invite to go diving Aaron, doesn't look like I'll have any time. But hopefully we can talk on the phone before I leave.

Couple of points:

1. Yasemin's thoracic filling: I think what she is referring to is the non-traumatic seeping of plasma into the lungs to protect them on very deep dives. I don't remember if this has been proven or if it is theory. I know that some deep freedivers "feel" plasma filling their lungs on dives over 60m+. Apparently, it usually retreats into surrounding tissues as the diver ascends. Sometimes it won't completely clear up and a diver will cough once or twice, but I believe in general it is clear fluid and not bloody. Yasemin's equalization with seawater has nothing to do with "plasma filling" of the lungs.

2. My theory about the cause of squeeze could be tested and I'm working on finding a physiologist and doctor to try to do some follow up experiments to test my theory. Basically, the more pressure on your lungs and heart from lung volume, the higher the risk of squeeze. What I would like to measure is the effects of packing on blood supply near the lung and in the thorax and also measure the amount of time required for it to return (if the first part is proven) versus a given increase in ambient pressure. Or you could separate it into two parts: 1. speed of descent vs. blood pooling (constant lung volume) and 2. lung volume vs. blood pooling (constant descent speeds).

3. From my personal experience and by talking with other divers, I've narrowed down a list of most crucial factors contributing to squeeze:
-speed of descent (especially in first 30m)
-lung volume (higher lung volume increases risk of squeeze)
-flexibility and elasticity of thorax (rib cage, muscles, and connective tissues)

4. I believe that other contributing factors include:
-hydration levels
-tension and anxiety
-body position or movements (arms)
-body temperature
-sudden jumps in depth
-breathing efficiency
-cardiovascular fitness (if you pack to the max, what effect and pressure must the heart overcome to ensure proper blood flow to the lungs and thorax?)

5. I also can say from my own experience that having congested lungs is almost a guarantee for some sort of squeeze episode

6. There is a difference between squeeze of the esophagus or upper bronchii and a barotrauma of the lungs. In my opinion, the difference is in the symptoms of coughing, wheezing, volume of blood coughed up, and long term symptoms like pain, difficulty breathing, dizziness, weakness, etc... So far people with esophagus squeezes don't have persisting symptoms or much more than a little blood after surfacing.

7. Many, many freedivers flirt with squeeze and are in denial about how close they are to having a bad episode. Most of them are in the 25m-55m range.

8. I haven't met any instructors who really paid attention to squeeze and how to avoid it in their course curriculum. Probably because they haven't experienced it themselves.

My protocol for avoiding squeeze is as follows:
-good cardiovascular shape (which is sometimes at odds with training methods that I prefer)
-FRC warm-ups for exceptional chest flexibility (30m+)
-staying warm, hydrated, relaxed and confident
-slow descent speed in the first 30m (0.5-0.7 m/s)
-minimal packing

I feel that this routine gives my body the chance to adapt to the stresses imposed on it by deep dives. I've had to adopt it out of necessity, since my lungs seem more easy to squeeze than most other people's. But I know that a lot of other people are at risk.

If anyone else has theories or questions, I'm glad to hear them.


Pete Scott
Vancouver, BC
esophagus? don't you mean the trachea?
thanks for your continued input & enjoy your vacation!
Thanks all,
I also had the raspy/gurgling sound at the forced end of exhale, and although I didn't feel any shortness of breath, when we began the swim back to shore I tired out much more quickly than normal. Streching, hydration, decent speed, excessive packing and tension I believe were factors, but the attempted inhale was what got me I think. I may have been fine if I had everything else in order. I'm going to take 6 weeks for recovery.

Sooner or later I'll be in Vancouver and I'll give you a shout for a dive! Have a great time on your vacation!

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