The untold story of the daring cave divers who saved the Thai soccer team

[Greenjuice]

Hello,

The article I mentioned that describes the anaesthetic process in detail and also some testing of the full face masks used with particular emphasis on their ability to maintain constant positive airway pressure has just gone freely available on PubMed

I have also attached it to this message.

The anaesthetic story is fascinating, and many of you who might have been considering FFMs will find it interesting.

Simon M

Much appreciated thanks. Good to see the clarification and distinction between sedation and anaesthesia. In our paediatric medical MRI practice it was clear that most of what was termed sedation was actually anaesthesia.

By odd coincidence, I believe today marks the anniversary of the third and final cave dive day of the rescue, when they brought out the four children and the coach, with Harry and Chris completing their good work.

 

[Akimbo]

How did they secure it to the bottom?

 

[rmssetc]

@Akimbo How did they secure it to the bottom?

I have no direct knowledge, and it's hard to tell from the photo, but it looks like there are bolt hangers, as frequently used in rock climbing and caving, particularly on limestone formations. The carabiners and rope look familiar from climbing.

It's possible to hand-drill holes for bolts, but that would be incredibly difficult underwater. I suppose they used a submersible hammer drill.

 

[tursiops]

How did they secure it to the bottom?

I have no direct knowledge, and it's hard to tell from the photo, but it looks like there are bolt hangers, as frequently used in rock climbing and caving, particularly on limestone formations. The carabiners and rope look familiar from climbing.

It's possible to hand-drill holes for bolts, but that would be incredibly difficult underwater. I suppose they used a submersible hammer drill.

Here is a segment of the photo, AI enhanced. You can see the carabiner in the upper right.

 

[Akimbo]

Here is a segment of the photo, AI enhanced. You can see the carabiner in the upper right.

I am more curious about what the carabiner was fastened to. Concreted padeyes, some sort of piton, climber's wedges/cams? It is a lot of buoyancy to hold against, I'm guessing around a ton.

 

[rmssetc]

I am more curious about what the carabiner was fastened to. Concreted padeyes, some sort of piton, climber's wedges/cams? It is a lot of buoyancy to hold against, I'm guessing around a ton.

As a climber, limestone is terrific rock for the surface texture and frequent pockets for fingers & toes, but it's rather brittle and it's rare that limestone is climbed with "traditional" gear (removable devices that don't scar the rock) such as wedges or cams. Limestone climbs are almost always bolted -- a bolt can be installed in more places, particularly in a textured surface that doesn't have cracks that would accept removable gear, and is stronger than removable gear.

Climbers would almost never use pitons in limestone. A cam (an active piece of removable protection) is rarely used in limestone. A climbing wedge (or chock, or "nut") can be used, and could conceivably hold underwater, but that would be entirely subject to the presence of a constricting crack in just the right place, at the correct angle to the force on the nut.

From what I can see in the photo, there are bolted anchors installed in the rock -- those involve a drilled hole, a bolt (an expansion bolt which can be placed underwater without significantly affecting the strength of the anchor, or possibly a bolt set in concrete) and a fixed metal ring to which the carabiner is attached.

 

[Dr Simon Mitchell]

Sorry about the delay in replying. I have been teaching on a DAN DMO course at Little Cayman - very pleasant diving and a great group!

We used a pneumatic drill and expansion bolts as rmssetc suggested. The walls in that cave are predominantly marble. Akimbo is right - its a lot of buoyancy. I'll ask Harry, but way more than a ton. We installed the habitats early in the expedition and let them sit there for at least 3 or 4 days before actually using them. I must say, the dire consequences of the moorings breaking with divers inside did haunt me, but I just added it to the collection of "what could possibly go wrong" things on a 245m dive in 6 degree water over 16 hours.

Simon M