Accident & Incident Discussion - Northernone - aka Cameron Donaldson

[rjack321]

LcF suffered a severe fall off of one of her show horses just days prior to her death, the plausible theory then was an undiagnosed head injury that may have caught up with her on that infamous dive.

not head injury, pulmonary embolism

Even a tiny crack/break in the hip triggers a cascade of systemic effects which dramatically increase the risk of clotting. If you throw one of those clots, it ends up lodging in your pulmonary capillaries and can easily be fatal. This is the same as deep vein thrombosis, and the reason passengers on long haul airline flights are recommended to move around.

note the incidence of PE after hip fractures
"Venous thrombosis is a substantial cause of morbidity and mortality in patients following hip fracture (Todd et al. 1995). Asymptomatic deep vein thrombosis (DVT) has been reported in up to 50% of all patients who sustain a hip fracture, with an incidence of fatal pulmonary embolus (PE) of up to 10% (Haake and Berkman 1989, Todd et al. 1995, Zahn et al. 1999)."
Symptomatic venous thromboembolism following a hip fracture: Incidence and risk factors in 5,300 patients

I don't think that's what happened here to Cameron, but it does serve to highlight that there are actually quite a few medical events besides a heart attack or stroke which can be fatal on a dive.

 

[scubafanatic]

I'm wondering how his mom didn't seem to report any unusual currents/severe conditions on her dive, (unless I missed that amid the lengthy thread somewhere) they dove in the same place at the same time, she makes it back just fine, but Cameron is suddenly, mysteriously swept away ? Would the two of them experienced such radically different dive conditions given they were in essentially the same place at the same time (other than differences in max dive depths) ?

 

[Timmy V]

I'm wondering how his mom didn't seem to report any unusual currents/severe conditions on her dive, they dove in the same place at the same time, she makes it back just fine, but Cameron is suddenly, mysteriously swept away ? Would the two of them experienced such radically different dive conditions given they were in essentially the same place at the same time (other than differences in max dive depths) ?

The current can vary dramatically at different depths.

 

[KathyV]

This is a Google Translation so it's not great but I think that you can make out some of the main comments.

https://sipse.com/novedades/buzo-extraviado-fotografo-plazo-protocolo-busqueda-cameron-donaldson-327395.html

March 21, 2019

Little chance of finding a lost diver

Last Monday the 72-hour deadline set by the protocol in the search was met.

Gustavo Villegas/SIPSE

COZUMEL, Q. Roo. The last person who saw with life the diver and photographer Cameron Donaldson was his mother at the time of receiving the camera with which he made perhaps the last photographs of marine life in Cozumel.

By that time, Bonnie Patricia had spent 40 minutes diving with her son in the Cantil and was at the time limit of the safety tables of recreational diving, explained César Zepeda Escamilla, president of the ANOAAT in the insula.

Monday was the deadline of 72 hours that marks the protocol in the search for a diver lost by the Semar before suspending it, instances that keep absolute silence in what is the fourth episode of this type of incidents so far of the year.

The providers of local water tourism services joined from the afternoon of Saturday, March 16, to the search of the Canadian who was reported by his mother after several hours of not returning to the coast from the point known as "The Rocks" in the area. north of the island Cozumel.

From the point of view of César Zepeda, breaking the security rule of not diving from the beach was the first mistake made by the photographer who in his dives captured countless marine organisms from the reefs of Cozumel. The recreational diving in the "walls" of the island must be supported by a boat, it is a basic safety rule that broke many times and it was recommended not to do it and leave from the shore to the cliff. In his experience, if the diver were floating by the currents, at this moment he would already be in the Yucatan Channel; in the event that he could have risen to the surface. However, the president of the National Association of Operators of Aquatic and Tourist Activities (Anoaat), opined that what could happen is that he suffered some incident while under the surface as an oxygen toxicity or an anesthetic for exceeding the time of diving.

Germán Yánez Mendoza, diver and spelunker of the island, said he knew the Canadian and knew of his diving skills, not only in the sea, but in caves on the island. He is a highly trained diver, very experienced and in excellent physical condition who used to use two tanks.

Meanwhile the Secretary of the Navy of Mexico has not issued any of the search until the close of this edition. However, unofficially, it could be known that a CASA C-295 aircraft combed the area in an attempt to find floating abroad.

 

[Scared Silly]

I’m not sure the right word is “confidence” - it’s just that given his age and physical condition it doesn’t seem likely he had a medical event at depth.

Even that statement is specious. None of us posting know Cameron's detailed medical history. Being young does not mean being invincible. We like to think that but it is far from accurate. One can be well prepared but then still have a medical event that is unsurvivable. He could have had a medical condition unknown to him, for instance a PFO.

People want to be believe certain things because there is no explanation. At this point Cameron is missing, that is mainly all we know. This type of incident is not the first for me as I have seen similar in the high mountains where climbers just disappear. It is weird, it is unsettling, but most of all it sucks when you are there and/or they are your friends.

 

[scubafanatic]

The current can vary dramatically at different depths.

True, but you'd be in the deep current very briefly, and if deemed dangerous an experienced diver would proceed to surface (I assume) once you surface you'd be back in the same surface current 'mom' experienced which posed no obvious issues for her. I few minutes in a deep current isn't likely to make you irreversibly Cuba-bound.

 

[CWK]

.
.
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Monday was the deadline of 72 hours that marks the protocol in the search for a diver lost by the Semar before suspending it, instances that keep absolute silence in what is the fourth episode of this type of incidents so far of the year.
.

Fourth SAR this year? Were any of the others found?

 

[Steve_C]

True, but you'd be in the deep current very briefly, and if deemed dangerous an experienced diver would proceed to surface (I assume) once you surface you'd be back in the same surface current 'mom' experienced which posed no obvious issues for her. I few minutes in a deep current isn't likely to make you irreversibly Cuba-bound.

I could be wrong but I envision a sloping bottom and then a wall. Cameron goes over the wall. Mom up on the slope and returns up the slope. Carmeron, if he ever comes up, comes up off the wall in the currents. I can see how the situation would be different for the two divers.

Also if I understand the post above correctly cameron goes over the wall after diving for a bit with his mom so he did not have two full 80s.

 

[Dan]

I could be wrong but I envision a sloping bottom and then a wall. Cameron goes over the wall. Mom up on the slope and returns up the slope. Carmeron, if he ever comes up, comes up off the wall in the currents. I can see how the situation would be different for the two divers.

Also if I understand the post above correctly cameron goes over the wall after diving for a bit with his mom so he did not have two full 80s.

For 40 minutes, I read somewhere.

 

[RayfromTX]

The discussion seems to be centered on the philosophy of solo diving and a very subjective discussion of risk – both avoidance and acceptance of it. However, so far we haven’t had one person, run the numbers on the dive. It seems we have a reasonably detailed idea of the dive profile, depths and time and the gear selected, but nobody has gone to the trouble to demonstrate that this is a run of the mill solo technical dive with adequate gas supply or otherwise.

As indicated yesterday, I did an extremely crude estimate on the back of the envelope and my conclusion was that it was “tight”, however any estimate is based on an ASSUMED RMV unless someone has more specific information.

Can any of the qualified tech divers show a profile that they themselves could safely run with twin 80’s of air to 150 ft accruing 30 plus minutes of deco? Perhaps using their own RMV’s for the working part of the dive and maybe a reduced one for the deco? This might add some objectivity to the discussion of risk etc.

I think discussing the factors that we do know should be looked at before we diverge into opinions about a hundred potential scenarios or situations for which there is little or no actual information.

Scooter failures, medical issues, scuba unit failures, BC failures, extremely unusual down currents, potential diver errors, the potential of an aggressive shark, failure to locate the diver on the surface, decompression sickness - and who knows what else are all possible scenarios, and none of them are mutually exclusive. The potential scenarios that can reasonably be developed without the benefit of more information is almost unlimited.

0.5? IMO, a generous RMV given the supposed conditions, scooter or not.

Be that as it may, seemingly by those calcs, uping it to even 0.8 would have still made it (with not a lot to spare, admitedly). I'm somewhat surprsed. Shows how long ago I had to calc an OC dive I suppose.

An RMV of 0.5 seems pretty unrealistic at this site on this day. Especially in light of other dives in the neighborhood and "clawing back up to 70ft" kinds of reports. That said, I don't think 10mins on air at 150' in Coz with 2x al80s is totally crazy talk. It's not for me, and I think the risk profile for deep-ish air isn't worth it, but not insanity.

Looking at the 6.6g/L density of air at 150ft gives me the shivers. The air and the deco were no doubt accentuating the risks, but like most incidents there's rarely just one thing to point to as a conclusive flaw. Right now we have solo, very high currents, dense narcotic gas, depth, likely deco, and perhaps a personal tendency to turn around "late" all pitted against relative youth and extensive site experience. That's a lot in the "against" column and not much in the "asset" column.

I can give some input into Cameron's SAC rate or RMV if you prefer. I just checked a shore dive we did on 1-1-2018. We swam into a current for the first 2/3 of the dive. Cameron carried his big camera rig and was using some odd fins he had never worn before because he was testing some silly fins for someone and let our other friend use them for the dive to try out so Cameron was using his full foot whatevers that were somebody's cast offs. He took some great photos that required some positioning and we found some lion fish in nooks and crannies along the way. I started with a full AL80 and he started with an AL63 that had 2,000 psi. We finished the 90 minute dive essentially empty(176 psi) in waist deep water. The depth averaged 20 feet and max was 39. That comes to around .28. I think he told me on several occasions that his sac was in the mid to high .2s on cave dives with a camera and no scooter and his mom was around .23. He sipped air. I can't say what happened when he got into a stressful situation because I never saw him stressed. I've read about it here though.