11 y/o Surfaces with Convulsions

[doctormike]

Sure, I understand... and I don't mean to be pedantic about this. I know that you are trying to learn and help, just like the rest of us.

The main difference I see between this forum and an actual accident investigation is that we almost never have access to even the most basic, accurate information about the actual event. Also, our mission isn't to find out what happened to THIS kid, but to discuss (as you are doing) the likely and unlikely reasons to explain the facts that we do have.

DCS and Ox Tox are clearly ludicrous things to consider in a 17 foot dive, but I don't think that anyone was suggesting them. Barotrauma, on the other hand, is a very real risk when anyone breathes compressed gas at depth, and is especially a consideration when the diver is a child who may not follow the instructions so well and hold their breath on ascent. So it's worthwhile discussing it, to underscore to people reading this thread that it is a real risk, and one of the few risks that are there even on very shallow dives.

People often are quick to say that a death was from "medical causes", which implies that diving had nothing to do with it. And sure, we are divers, and psychologically we tend to minimize the risk. So yes, a 68 year old obese diver who dies on a dive could have had a heart attack. But the heart attack might not have happened without the stress of the dive, and might well have been survivable on land.

Similarly, some 11 year olds do develop new onset seizure disorder, but I would strongly consider that a seizure on surfacing was diving related - possibly from hypoxia or AGE.

 

[Biotech Diver]

Sure, I understand... and I don't mean to be pedantic about this. I know that you are trying to learn and help, just like the rest of us.

The main difference I see between this forum and an actual accident investigation is that we almost never have access to even the most basic, accurate information about the actual event. Also, our mission isn't to find out what happened to THIS kid, but to discuss (as you are doing) the likely and unlikely reasons to explain the facts that we do have.

DCS and Ox Tox are clearly ludicrous things to consider in a 17 foot dive, but I don't think that anyone was suggesting them. Barotrauma, on the other hand, is a very real risk when anyone breathes compressed gas at depth, and is especially a consideration when the diver is a child who may not follow the instructions so well and hold their breath on ascent. So it's worthwhile discussing it, to underscore to people reading this thread that it is a real risk, and one of the few risks that are there even on very shallow dives.

People often are quick to say that a death was from "medical causes", which implies that diving had nothing to do with it. And sure, we are divers, and psychologically we tend to minimize the risk. So yes, a 68 year old obese diver who dies on a dive could have had a heart attack. But the heart attack might not have happened without the stress of the dive, and might well have been survivable on land.

Similarly, some 11 year olds do develop new onset seizure disorder, but I would strongly consider that a seizure on surfacing was diving related - possibly from hypoxia or AGE.

I agree with you. AGE wasn’t something that initially came to mind. I was thinking something like an epileptic seizure but I think it’s a real possibility the kid may have held his breath and come up to the surface.

 

[BRT]

I'm new to diving but I grew up diving to the bottom of swimming pools and I'm not aware anyone got hurt doing it. It's actually required in Life Guard training I believe. Where I live in the boonies people do crazy stuff like jump off cliffs into lakes and I'm sure you go down to at least 15 feet under the water. I've only jumped from 40 feet but others go much higher.

I'm calling shenanigans on AGE from 17 feet.

Diving from the surface and on SCUBA are 2 different things.

 

[GJC]

Boy airlifted following dive incident in good condition at hospital

An 11-year-old Rochester, Minnesota boy airlifted to Miami Tuesday morning following a dive incident at Looe Key Reef is in stable condition and is expected to make a full recovery.

The Sheriff’s Office was notified at approximately 10:49 a.m. that the boy was diving in 20 feet of water with family and a divemaster with a commercial dive boat out of Captain Hook’s Marina and Dive Center. They were in the water approximately 35 minutes.

Everyone surfaced. The boy blacked out and began convulsing. He was conscious and breathing.

The boy was flown via Trauma Star to Nicklaus Children’s Hospital in Miami.

Interesting case. Sounds very much like a shallow water blackout that can occur after deliberate hyperventilation for a breath hold dive even though he was using scuba.

Full recovery with no apparent cause found at the hospital for a seizure is not unusual for kids. Kids can seize when they have a fever, adults usually don't. A hypoxic episode can trigger a seizure in kids that they fully recover from.

So to me, it sounds like he probably held his breath too long, for whatever reason, and his oxygen level dropped enough for him to pass out and have a seizure. Being on the surface, he was able to breath on his own until his oxygen level increased and he woke up. The trip to the hospital was still a good idea to make sure nothing else was going on (like AGE, or hypoglycemia or a brain tumor unrelated to the dive).

 

[Akimbo]

Sounds very much like a shallow water blackout that can occur after deliberate hyperventilation for a breath hold dive even though he was using scuba.

This might be misleading. Blacking out from hyperventilation is not the same as shallow water blackout. Extreme hyperventilation can cause the Carbon Dioxide (CO2) in your lungs and blood stream to fall too low to stimulate breathing, which causes the body to shut down.

Shallow water blackout occurs when freedivers consume enough oxygen that the PPO2 in their lungs and blood stream at depth falls near hypoxic limits. They black out from hypoxia on ascent when the pressure drops and the PPO2 becomes too low to support consciousness.

That wouldn't be possible for a Scuba diver, even in 20' of water, because their tissues are hyper-saturated with Oxygen from their time at depth. It would require holding their breath on the bottom long enough to deplete the O2 in their system, which would cause very high CO2 levels. That is very hard to do voluntarily. An OOA diver might black out for CO2 poisoning, but that can't sneak up on you. In addition, holding their breath on ascent would embolize them.

It is not uncommon for freedivers that push their limits too far to black out just after reaching the surface and taking their first breath. Their tissues are depleted enough that their first lung full doesn't get into their blood stream before the body triggers the blackout, which is basically shutting down everything except blood flow to the brain. The problem is freedivers will fall face-down and drown if their buddy isn't there to help.

Freediving courses train you to dive in teams so their buddy stays on the surface while the other dives. The buddy follows the diver and is there when they break surface. The diver is supposed to signal the buddy for about 10 seconds, through hand signals or speech, until the risk of blackout on the surface passes. Of course the buddy is there in case the diver blacks out before leaving the surface. Buddies in competitive apnea diving will dive down to meet their diver at around 30'/10M and follow them up. Deep freedivng buddy pairs may also do that but it might not be practical in low visibility.

This is extremely rare with inexperienced and otherwise untrained freedivers because their tolerance to CO2 isn't developed enough to deplete their Oxygen that low under normal conditions. CO2 buildup is what causes the desperate urge to breath, not low Oxygen. Freedivers can develop a tolerance to CO2 over time and through conditioning. That was especially interesting to me because the amount of time past the point where you start to feel desperate to breathe is MUCH longer that you would imagine before you actually black out.

The lesson for Scuba divers is don't panic, which is really hard to do with CO2 buildup, but can easily be the difference between killing yourself and having a great sea story to tell your grandchildren.

 

[DandyDon]

Has no one else seen Carbon Monoxide as a possibility? The tank would have to have a high ratio to hurt someone at 15-20 feet, but it's possible. Ascending is when PPCO poisoning kicks is the worst, convulsions are a common symptom, having only one tainted tank of a lot certainly does happen, and most divers & Ops don't bother testing. Plus, there probably will not be a controlled tank after the injury so no report.

 

[kelemvor]

Plus, there probably will not be a controlled tank after the injury so no report.

Don't they usually collect scuba gear so it can be analyzed after dive accidents?

 

[DandyDon]

Don't they usually collect scuba gear so it can be analyzed after dive accidents?

I've seen six divers carried away in ambulances but have never seen that done, altho most of those were outside of the US.

 

[kelemvor]

I've seen six divers carried away in ambulances but have never seen that done, altho most of those were outside of the US.

Luckily, I've never seen a scuba accident that required an ambulance in person.

 

[Akimbo]

Ascending is when PPCO poisoning kicks in the worst...

I don't understand. Wouldn't reducing the PPCO by ascending be a little less terrible? Come to think of it, reducing the PPO2 by ascending would have a significant negative effect on someone already compromised by CO poisoning. Reducing the PPCO is a good thing but doesn't help very much if you are already overloaded with CO.

For other readers, increasing the PPO2, ideally well above 1 ATA in a chamber, is the standard of care for treating CO poisoning. Carbon Monoxide is so insidious because it is several times more readily absorbed by hemoglobin than Oxygen. Hemoglobin basically gets clogged up by a biologically useless gas instead of carrying Oxygen to your tissues. Just breathing fresh air, or even pure Oxygen, on the surface may not save a life from CO poisoning.