Ever experience a SWB?

Anyone ever have, or witness, a shallow water blackout? Care to discuss?

freediver:

Anyone ever have, or witness, a shallow water blackout? Care to discuss?

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my older brother died five years ago of shallow water blackout when he was 19. he was under water for about 10 minutes before he was found and the resussitation failed. aparently if it had worked he may have been seriously brain damaged.

he had been hyperventilating before going under water. it seems clear to me that doing this is the most ridiculous risk and it should be discouraged by everyone. he learnt about it at Coral Cay (a conservation company) which organise conservation programmes which you can pay to help out at. my brother saved for a long time to pay to be part of one of their programmes, and i remember his emails saying that he felt like he was destroying the coral rather than helping it. so i don't think they're a great organisation at all. especially as they condone hyperventilating before going under water. they should discourage it actively as it increases chance of shallow water blackout by a huge amount. free diving is a hugely irresponsible sport in my opinion. use proper diving equipment, or don't try to stay under water for any considerable length of time. what is the point in that, when you could die the most pointless of deaths by running out of breath. what a waste of life and a brilliant person and brother.

emmava18,
My condolences for the loss of your brother. You have my sympathy. I won't comment on your bias against freediving ,as I'm sure it will only cause controversy, except to say I don't share your sentiment.
As for swb, I have never expeirenced it. I dive conservativly and try to always dive with a compatent buddy. I'm not saying it can't happen to me but I do believe the risk can be diminished by using proper safety and knowing/following your limits on any given day. Also I blelieve it is smart to make sure you have a nice long surface interval. To many times I hear of spearos diving deep, seeing a fish at the end of thier hold and rushing their surface interval (sometimes just long enough to get one breath) and heading back down to bag the fish. And I hear of them doing this all day long. To me that's just asking for disaster.
Later,
Stitch

emmava18:

my older brother died five years ago of shallow water blackout when he was 19. he was under water for about 10 minutes before he was found and the resussitation failed. aparently if it had worked he may have been seriously brain damaged.

he had been hyperventilating before going under water. it seems clear to me that doing this is the most ridiculous risk and it should be discouraged by everyone. he learnt about it at Coral Cay (a conservation company) which organise conservation programmes which you can pay to help out at. my brother saved for a long time to pay to be part of one of their programmes, and i remember his emails saying that he felt like he was destroying the coral rather than helping it. so i don't think they're a great organisation at all. especially as they condone hyperventilating before going under water. they should discourage it actively as it increases chance of shallow water blackout by a huge amount. free diving is a hugely irresponsible sport in my opinion. use proper diving equipment, or don't try to stay under water for any considerable length of time. what is the point in that, when you could die the most pointless of deaths by running out of breath. what a waste of life and a brilliant person and brother.

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I'm sorry to hear about your loss. You mention using proper dive gear above, are you a SCUBA diver? Diving of any kind has its dangers. If you are interested you might consider posting some details of this in the accidents and incidents forum where it could serve as a warning to others.

Again, my condolences.

James

To answer the original question... I have. But you don't freedive without a buddy, and it's always one on the surface watching the other who is at depth.

Mine happened in a pool where I was doing training (long underwater swims). My buddy was the lifeguard, and I made a point of discussing with him my regimen and asked if he would keep a close eye on lane X. I do this EVERYTIME I train so they are rather used to it. It's not unusual for me to see the lifeguard at the end of a longish swim there to congratulate me.

But one day I wasn't feeling well. I had a bunch of laps planned. 1/4 mile freestyle, 1/2 with fins & snorkle, and then 4 relatively benign 50 meter underwater swims. But I had the flu, and probably shouldn't have even been near the water, much less in it.

Every task took it's toll for me that day. Each lap was agony, but I was determined to finish my regimen. It took me a full 20 minutes after the fin and snorkle before I attempted the underwater swims.

The first one was a lung burster. I almost didn't make it to the end. The second was not quite as bad as I finally felt my heart start to relax. On the third trip I was about half way, when I got a "second wind". I knew I was going to be able to go for a 100 meters on this try. The next thing I remember I was fighting with John, the lifeguard. I had no idea why he was manhandling me like he was, but boy I felt weak. My face slipped into the water during our "struggle" and I aspirated pool water. Gagging and feeling like my chest was imploding I was pulled from the pool by the lifeguards and swimmers. I was put into the recovery position and EMS was initiated. I developed subsequent pneumonia from the event and was out of diving for a couple of months.

Were the three hyperventilations I took for this the cause? Nope. If you limit the number of hyperventilations to 3 or 4, you shouldn't fool your body enough. But I had no business being in that water... I was sick. No, it wasn't really a "dive", so I didn't think to call it. I have called dives and even training dives on account of being sick. But I was intent on meeting a certain goal. THAT'S what caused it. Normally 50 meters under water are a piece of cake for me. Crumb cake. Not that day.

But even more important than "pushing" myself beyond my physical limits, I had taken the proper precautions. My buddy was prepared. What could have been a tragedy for my family was averted because I chose to have a buddy watching my butt for me.

If you learn ANYTHING from this thread, then I hope that it's these three points:

1) It's easy to push yourself beyond your physical limitations. There is nothing down there to see that is worth your life.

2) Dive properly. Take a class. Sure it's intuitive, but there are rules you should follow!

3) Dive with a buddy. One up while one is down.

Caveat: For some reason since this episode, my sac rate fell dramatically and free diving became far easier. I am not sure why, and I really distrust my "out of air" feelings because of it. Currently I limit my freediving depth to 40 ft and shallower.

Emma, your feelings about free diving are obviously very heartfelt and for a good reason, I have personally lost three ex students of mine to apnea and SWB. I now find when I teach young fit healthy Divemasters, I spend about an hour explaining to them why the movie "the big blue" can kill them as it did three of my previous students.

The normal scenario is a young fit new and enthusiastic dive professional, sees a movie like big blue, or hears about Pippin, then starts to test their own limits to see how deep they can free dive. This os often by themself, during a surface interval or on a day off when no one is around and it has tragic consequenses. I agree with you, apnea, particularly apnea for depth records is a stupid and dangerous sport, you are testing your bodys limits, unfortyuantely, when you find where those limits are, you are about to die unles you are rescued by someone else.

Here is a diagram that I drew that explains the cause of SWB with respect to the partial pressure of the gasses CO2 and O2

hello again,
i had a bit of a rant yesterday about free diving. i still think it's irresponsible because of the risks but i guess lots of sports are risky, you just have to be safe don't you? i'm afraid you caught me on a bad day, bored at work, just looking on the internet trying to find out more about shallow water blackout, what my brother died of. his friend was off swimming somewhere else so if they'd been doing the one person up one down thing it wouldn't have been such a disaster. you are all very nice to give condolences. and as for your diagram cancun mark, well i would never be able to understand that! be safe all of you.

Mark,

Depth usually plays a big part as well. The deeper you go the higher the pressure in your lungs becomes, artficially increasing your partial pressure of oxygen and allowing you to consume it faster.

As you ascend the partial pressure decreases with the pressure often resulting in a blackout just under the surface.

My experience was an anomaly as I had kept at the same depth the whole time.

Either way, we agree that all apnea/free divers and snorklers should always dive with a buddy! This applies to rebreather divers as well. There are little or no symptoms when you are going to black out. It can and will happen to you when you least expect it.

I also agree that "record" dives are pretty senseless. They prove nothing and take away everything.

Terribly sorry for the losses with each and every one who has posted. Tragic as the deaths are, I don't feel they can be blamed on an activity that has shown a superior safety record when performed correctly. As far as the competitive side of freediving, if you enjoy or have even heard of freediving then you can likely thank Jacques Mayol and Enzo Maiorca for their engaging rivalry and their record setting attempts. Without these guys, freediving would be a relative unknown. Much like SCUBA, thanks to a couple guys, ohhh Cousteau and Gagnan i believe, that had the nads to venture out beyond a comfort zone and expose the sport to countless numbers. Contrary to some belief, freedivers are not dropping left and right and even the competition divers have a superb safety record when diving properly and all safeguards are in place.
I, too have lost a dear friend in the water but it was while spearfishing, which is inherently more dangerous than freediving.
I also have video tape of another friend suffering a blackout in Cayman. I teach clinics and, believe me, the issues of safety are paramount.
As an avid freediver, i can tell you that the one thing I want to do is improve myself as a diver. This cannot be accomplished WITHOUT testing and challenging my limits! This is why safety and conditioning is stressed. I have trained and dived for 16 years without incident simply due to the fact that I obey ALL principles of safety. I look forward to several more years of safe diving and can only hope that everyone would have a shared interest in a great activity.

freediver:

it was while spearfishing, which is inherently more dangerous than freediving.

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I agree with that statement one hundred percent. It's usually the goal oriented dives that lead to a hightend danger of black out. And spearing falls smack dab into that catagory. I think spearing can be just as safe as competitive freediving but unfortunately most spearos don't take the time to dive safe. If they even have a buddy they are typically spearing at the sametime several meters apart which totaly nullifies the advantage of having a buddy. I'm not trying to get down on spearos I'm only pointing out that it's an all to common problem among the spearing community imo.
That being said, competitive freediving is also a goal oriented sport but typically safety precautions are taken to ensure that the divers are cared for if they suffer a b/o. And sadly those competitive deaths that have occured ,in most cases, could have been avoided if proper safety had been followed. i.e. checking lift bags for air or proper working condition.
Recovery for a b/o victim, if retrieved in a reasonable amount of time, is not complicated in the least but unfortunately a lot of divers don't take the time to learn thus contributing to deaths. For instance , in most cases, all that is required for a b/o victim to regain conciousness is for the mask to be removed. The air hiting sensors around the eyes usually forces the body awake and normal breathing resumes. If that doesn't work a light breathe on the eyes will most often do the trick.


Here's my list of do's and don'ts. I want to give these in order that someone might be spared in the event of a b/o. If anyone has any modifications or additions that would be great. I by no means know everything nor do I claim to.
NEVER DIVE WITHOUT A COMPATENT BUDDY
USE THE ONE UP ONE DOWN RULE. MEANING WHILE ONE PERSON IS DIVING THE OTHER WAITS ON THE SURFACE IN CASE A RESCUE IS NEEDED.
PLAN YOUR DIVES. TELL YOUR PARTNER HOW LONG YOU PLAN TO BE DOWN. DON'T GO BEYOND WHAT YOU DISCUSSED.
IN LOW VIS SITUATIONS OR SWIFT CURRENTS , USE A DIVE LINE. DON'T STRAY FROM IT. IT'S WISE TO USE A WRIST LANYARD IN CASE YOU DO B/O YOUR BUDDY CAN FIND YOU.
DON'T DIVE BEYOND THE DEPTH YOUR BUDDY CAN. IF YOU NEED RESCUED AND YOUR AT 20 METERS BUT YOUR BUDDY CAN ONLY REACH 15, YOU'RE A DEAD DUCK.
NEVER, UNDER ANY CIRCUMSTANCES, HYPERVENTILATE. TO HYPERVENTILATE IS TO "BLOW OFF" CARBON DIOXIDE. CARBON DIOXIDE BUILD UP IN YOUR SYSTEM IS WHAT TELLS YOUR BODY YOU NEED TO BREATHE. IF YOU PURGE YOUR SYSTEM OF CO2 YOUR BODDY WILL NOT KNOW WHEN IT'S TIME FOR YOU TO BREATHE. BY THE TIME THE CO2 BUILD UP REACHES THE POINT TO GIVE YOU YOUR URGE TO BREATHE YOUR OXYGEN RESEREVE IS USED UP AND THE BODY SHUTS DOWN CAUSING A BLACK OUT.DON'T BREATHE EXCESSIVLY FAST OR DEEP. A GOOD RULE OF THUMB IS TO JUST BREATHE NORMALY AND THEN TAKE ONE LAST DEEP BREATH BEFORE SUBMERGING.
USE A QUICK RELEASE WEIGHT BELT. IN CASE OF TROUBLE DITCH THE BELT AND SAVE YOUR LIFE.
DIVE WITHIN YOUR LIMITS. EVEN IF YOU "FEEL GOOD" AT DEPTH BE AWARE THAT YOU USUALLY WILL DUE TO THE PRESSURE AND BLOOD SHUNT. WATCH YOUR TIME AND DON'T GO OVER.
DON'T FOCUS ON GOALS. OR DON'T SACRAFICE SAFTEY FOR A FISH OR FOR THAT EXTRA METER. IT'S NOT WORTH IT. BE AWARE OF HOW LONG YOU'VE BEEN DOWN.
KNOW HOW TO REVIVE AND RESUSITATE (SP?) A B/O VICTIM.
MAINTAIN PROPER SURFACE INTERVALS. DON'T STAY DOWN FOR TWO MINUTES AND COME UP FOR ONE. GIVE YOURSELF AT LEAST TWICE THE TIME AT THE SURFACE AS YOU DO AT DEPTH. IT WOULD BE WISE AND ADVISABLE TO GIVE YOURSELF FOUR TIMES THE SURFACE TIME AS DEPTH TIME.
IF YOU ARE OVERLY TIRED OR UNDER THE WEATHER, DON'T DIVE THAT DAY. IT CAN BE DEADLY.
THESE RULES ARE MEANT FOR RECREATIONAL FREEDIVERS AND SPEARFISHERMEN.

Sorry to be so long winded.
God bless and safe dives,
Stitch