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Trachea Lung Squeeze – cause and recovery questions.

Hey guys,

I just had a significant trachea/lung squeeze and would love to get some advice/opinions/resources as I plan my recovery and getting back into the water. I’m training for the Caribbean Cup in Roatan at the end of May.

Age: 43

Diving experience: Did the FII level 1 in 2013. No real freediving practice until 15 Feb 2015. Been line diving 2-3 times per week since then.

Static apnea: 5 min 30 seconds (no packing or hyperventilation)

Past FIM PR: 40m in 2:16. 3 days before squeeze.

Squeeze Situation: Went out with my buddy on April 3.

-- I was likely overhydrated, drinking over 3 liters of water that morning to make up for a dehydrated camping weekend. I also did no eat any breakfast.

-- During warmups, I did two forced exhale dives (no reverse packs) to 10 meters (novice move, I know now). No noticeable problems after surfacing. 3 regular warm up dives to 20 meters.

-- Went for my FIM deep dive with a goal of 45 meters.

-- I haven’t done much packing in the past, but did 5 or 6 packs before heading down.

-- I flip (changing to feet down, head up) on my descent at around 25-30 meters to make equalization easier. So I did that, equalized and kept descending. I tried to ‘force’ an equalization around 40m when that wasn’t successful, I did a contraction to get more air and was able to equalize and continue to 45m (a new PR).

-- Normally ascending from depth is a relaxed and fun part of my dive. I can take my time and enjoy it. Not this time. Every pull was tiring and I felt like crap with lots of “why am I doing this” type of thoughts. Total dive time was 2:14.

-- When I reached the surface, I had fluid in my lungs. I was coughing up red foamy saliva and couldn’t get a full breath. We went to the hospital. I was able to clear my lungs of fluid within about an hour of the incident without any medical intervention. And felt fine at that point (except for being in a hospital).

-- My SpO2. I didn’t look at it during the emergency but it had returned to 95-99% within an hour of arrival at the hospital. And stayed in that range for the 16 hours they had me under observation (the medical team had no experience with freediving or the concept of a lung squeeze so were reasonably worried)

Two days later I feel great. I’ve had a little soreness in my throat when I do a full inhale but no further coughing. But I don’t want that to happen ever again. So my questions:

1) What are some good up-to-date resources and research about trachea/lung squeeze.

2) How long should I wait to get back into the water?

3) How long should I wait to start getting back to depth?

4) What do you think was the likely cause? The forced exhale 10m dives during warm up? Something that happened at depth? Could the high hydration have increased the risk? Could it have been caused by traditional barotrauma during the ascent because I had good blood shift during the dive? A combination of all of the above? I know none of us are squeeze experts, but I’m interested in experienced freedivers opinions.

5) Most important, what should I do to prevent this from happening again short of giving up the sport all together? No forced exhale dives? No packing? More or deeper warm up dives before going for 40m+?


Well-Known Member
Jan 21, 2003
Sarasota, Fla
Hope somebody with serious squeeze and depth experience chimes in, but I've had more than my share (diving frc) so take this for what its worth.

Sounds like a pretty significant lung squeeze, might include trachea, but the lung is the real problem


1. Search through the DB threads. Much of the most up to date stuff is right here, or at least, it will lead you to it.

2 and3. Serious diving is much farther off than you think. You can probably get back in the water and do some shallow diving (assuming you feel fine and have no symptoms) pretty quick, just a few days. But be very careful and go slow. Serious diving to near your equalization limit is a long way off. This kind of thing is slow to heal. Push it and you just end up re-injuring yourself.Been there, done that, ain't fun.

4. Any and all of the above could be involved, but the fundamental problem is rate of progression. Depth takes a while. You are going way too fast.

Two things that will help you a lot. 1. do a lot of stretching, especially of the diaphragm and rib cage, intercostals, etc. This can substantially increase chest flexibility and depth ability 2. Do either a lot of FRC diving or dry exhale statics, every day. I combine dry with diaphragm stretches. Be careful with this until you feel healed, and then go slow. You can squeeze yourself again. once dry full exhale statics are completely comfortable, start adding some reverse packs, slowly. What both of these things do is stress the lung corpuscles through blood shift. They stretch, get thicker as a result and then can stretch more without leaking (lung squeeze) Unless you are diving frc almost every day, this is a slow process, but it has taken me much deeper.

I assume you are mouth filling. If not, learn how.


Mar 31, 2015
Los Angeles, CA
My understanding is that you should wait at least 2 weeks before you return to diving with a squeeze that bad. Once you do start again, it is recommended that you start at half your previous depth. Keep an eye on symptoms after each dive by waiting 5 minutes and spitting into your hand to look for blood. I can't really speak to your other questions but your deep forced exhale dives may be to blame, or head position during your normal dives.


Well-Known Member
Oct 26, 2012
What do you think was the likely cause? The forced exhale 10m dives during warm up?
If you are not used to such dives it could increase the risk of squeeze. Actually, these warm up dives simulated depth that was way above your PB.

Something that happened at depth?
Forced equalization at 40m and the attempt to get air out of the lungs were most likely the major cause.

Could the high hydration have increased the risk?
Definitely, overhydration increases blood volume which leads to increased blood pressure in the pulmonary circulation. The higher the pressure the greater the risk of squeeze.

Could it have been caused by traditional barotrauma during the ascent because I had good blood shift during the dive?
I don't think so. The fact that the ascend felt like crap and you got tired very quickly suggests that gas exchange in your lungs was already impaired. The squeeze most likely happened near the target depth.


Apr 6, 2015
I was ALWAYS told never to flip on a descent. If you can't equalize, return to the surface regardless of cause. Now, I'm not saying this is what caused the squeeze by any means, but it certainly increases your chances of LMC or blackout. And I agree, the forced equalization is almost certainly the culprit. Again, if you hadn't flipped earlier in the dive you wouldn't have ever attempted the equalization at 40m