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First Lung or Trachea Squeeze Incident (Any advice is welcome)

Thread Status: Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.


Apr 17, 2018
Just had my first squeeze so I thought I'd add my experience to the freediving body of knowledge... also would appreciate any advice regarding recovery/rehab and successfully returning to depth progression.

When I think back to what happened, the red flags that increased squeeze probability were being cold, 5m PB jump, using Frenzel at depth (instead of mouthfill). However, the causal factor was performing extremely forceful equalizations at depths below RV.

I think this was a trachea squeeze, not a lung squeeze due to equalization method used, bright red blood (not pink/foamy), pain location and no impact on %spo2. I could be wrong on that but I'm not sure it matters.

My recovery plan is to first take 2-3 weeks off all activity. Then I plan to start a training cycle where I spend 3 months doing a foundation segment. I'll focus on dry stretching (general, diaphragm, thoracic), dry fitness (apnea stairs, weightlifting, general cardio) and learning mouthfill (at above RV depths). After that I think I'll be ready to start gradual depth progression again.

Anything I'm missing? Any ideas to make sure this heals properly and doesn't become a recurring problem?

Incident Description:
Dive occured in San Diego, CA. Water temp was 22C at surface, 12C at depth. Water conditions at the surface were rough (whitecaps, 12-15 knot winds). Warmup consisted of 1/2 mile swim to deep buoy, 5 minute facial immersion and 4 warmup dives (hang, FRC, hang, FRC) before PB attempt of 50m (previous PB was 45m). Diver wearing old 5mm wetsuit, technisub micromask and breathing through snorkel.

I had to poop after the second FRC (classic...) so I had flooded my suit with water and was a little cold, but not shivering. My breathe-up was ~1 minute of slow inhale/exhale, 2 purge breaths and final 3 stage inhalation, no packing. Dive was a pull-down/kick-up so I started the dive pulling down the line. I had previously had issues of sinus squeeze due to incomplete equalization (only EQing ears instead of sinuses too). I focused on strong, forceful frenzel EQs to ensure complete EQ of ears/sinuses/mask. I hit neutral at ~10m and freefall at ~20m. Ahhhhh the good part... enjoyed freefall and the dive felt good as I hit the second thermocline ~30m. I noticed that I was drifting from the line so angled slightly back towards the line.

In my visualization of the dive I had pictured/planned to make equalizations less forceful once I hit 30m+, but I didn't. I continued forceful frenzel EQs. The last 2 or 3 EQs there was a weird sound coming from my throat when I equalized... grinding/gurgling? I hit the plate at 1:08 and thought I was all good. Started kicking up and felt strong. Met my safety diver at 15m, threw him a shaka, exhaled at 3m and hit the surface at 1:58. Completed surface protocol with no issues.

I had no issues for a while at the surface. Helped lift the line diving weight to the surface and started the 1/2 mile kick to shore. On the way back I started to feel a little off... maybe 15 minutes post dive? I did the spit check and saw that dreaded sign... bright red strings of blood in my phlegm. They were very small at first and then I got one that was a pretty big. Would estimate a tablespoon of bright red blood produced over ~ 1 hour. I experienced waves of nausea for ~30 minutes on shore. Very little coughing unless I attempted to bring up phlegm to do a spit check.

Checked %spo2 via pulse-ox at home about 1 hour post dive and was at 99%. Pain location was difficult to pinpoint immediately after dive but as the day progressed pain was felt in the center of the upper sternum. Pain continued into day 2 (and counting), but no blood or phlegm production.

Diving Background:
Male, 31 years old, 4.5 years of diving history (spearfishing less than 30m), 3 months of training beyond 30m (progressing from 30m to 50m) using reverse pack / frenzel EQ method, solid program of diaphragm stretching and line-diving 2x /week during that time
I do not have any recommendations for recovery but if you want to prevent this type of injury in the future you will need do a couple things. Be sure and reduce forces of upper body movement (turning on a line at depth) to a minimum. Ensure bringing air from the lungs during equalizing is done in smaller amounts and with more frequency, the Trachea is delicate and doesn't like large changes in pressure or movement at depth. You do not have to do a mouthfill but bringing air to the mouth gets more difficult with reverse packing as you go deeper. An indication of trying to move to much air at once when reverse packing is the straining noises you mentioned.
I woudl recommend listening to my podcast episode on lung squeezes.

I created the episode so every time I saw a Facebook post or forum post about it I didn't have to type the same stuff over and over again.

I think you will find it full of helpful advice and recomendations

Enjoyed the podcast! Will have to go through and listen to the rest of them.

Out of the possible reasons you mentioned... improper head position (no), improper movement (no), no warmup (no), contractions at depth (no), forceful EQ (YES), not relaxed (Kind of, tense at surface but I was comfortable after freefall started)

Based on spit check... I'd say level 1, maybe level 2 on one spit check.

I'm feeling way better. Pain was gone after 3 or 4 days. Here's my rehab so far:

Week 1: no diving, no exercise, no stretching, nothing
Week 2: back to general exercise, diaphragm stretching (no reverse packs), apnea exercise, nothing in the water

Starting next week, here's the plan:

Week 3: general exercise, diaphragm stretching (with reverse packs and contractions), apnea exercise, diving to 30m
Week 4: general exercise, diaphragm stretching (with reverse packs and contractions), apnea exercise, diving to 40m and FRC/RV
TBD: 40m->50m depth progression (and beyond)

I'm going to be changing over from "recreational/spearfishing" type diving (mask/snorkel, no lanyard, breatheup through snorkel with no packing, reverse pack + frenzel EQ) to "performance" diving (noseclip/ no mask, lanyard, breatheup on back with some packing, mouthfill + frenzel EQ) when I come back. It'll take a little while to get used to it so I'm not really in a hurry to get back to depth progression.

I'll spend a few months doing a high volume/low intensity cycle with lots of mouthfill EQ work, FRC/RV diving and deep hangs along with dry training. Then it'll be time to start pushing deeper again. Will keep this thread updated with progress and results.