Controlled Buoyant Lift

[DevonDiver]

Right ..... so ideally taught by instructors kneeling on the bottom, and wearing 2 or 3 BC's for redundant elevators

I get that this is aimed at low skilled students....However, my advice was to keep the non-responsive diver close to neutral while swimming up....which means this diver is constantly becoming more positively buoyant, and is constantly requiring the student to dump some air out....in your scenario, if this assisting diver gets suddenly challenged on the ascent, they would then stop dumping, and the non-responsive diver gets no more dumping, so the non-responsive one begins their positive ascent by themself if the assisting diver loses them. ( some of this is semantics in how you or I communicate an idea)....

As to how easy it is for a well trained diver to ride an elevator up properly....sure, it is easy when they are paying close attention--which we know does not always happen with many divers...but as you said, the skill is simple....With new divers, in sensory overload and little peripheral awarness----I think this is a recipee for polaris missile ascents, and worse still, it allows them to think that it is OK to Ride the BC up to the surface in their own ascending future--which it is NOT

But what you're suggesting is a Controlled Swimming Lift.

If we rule out technique based on assumption of diver incompetence, we'd be left with nothing. That'd include most of what GUE teaches, for instance.

Neither should we assume that teaching a skill would cause attribution of those principles to other skills. That would assume idiocy on behalf of the student.

I get the impression, and I may be wrong, that some of your objections stem more from a ''low regard'' for certain agencies, rather than a purely technical appraisal of the technique. That's prejudice clouding the issue.

The level of diver we are discussing is Rescue Diver. That course brings with it a distinct rise in diver skill demand. A diver who felt that 'a polaris-elevator ascent' was acceptable clearly shouldn't be training at this level. Simple as that. There is supposed to be pre-course appraisal of students before entering this training... so basic competence should be assumed.

 

[danvolker]

In training, ascents should be exaggerated slow. That's a safety/liability issue. In a real rescue, with a non-breathing casualty, speed is utmost. 18m/min is a 'safe' ascent rate from a recreational dive - it really is, in this context. I, personally, think there's many scenarios where I would risk even faster.

Again, context is everything; dive depth, how long the casualty (corpse?) has lacked respiration.... whether it's your ex-wife..

True..if it was someone I cared about, and they were not breathing, the likelihood is that my ascent would be a missile-like ascent--but on purpose, with no concern whatsoever for DCS--only concern would be for lung overpressure--easy for me, I guess you could bear hug the non-breathing friend and hope to expel air and avoid overpressure...

I have heard of a number of deep high speed recoveries that worked out well due to the speed of ascent and shortened time to CPR and mouth to mouth. What is your take on this?

 

[DevonDiver]

True..if it was someone I cared about, and they were not breathing, the likelihood is that my ascent would be a missile-like ascent--but on purpose, with no concern whatsoever for DCS--only concern would be for lung overpressure--easy for me, I guess you could bear hug the non-breathing friend and hope to expel air and avoid overpressure...

I have heard of a number of deep high speed recoveries that worked out well due to the speed of ascent and shortened time to CPR and mouth to mouth. What is your take on this?

I did one rescue...shallow... my only concern was speed. Took about 20 seconds to get to shore, adrenalin enhanced performance. Breathing resumed upon stimulation. Air ambulance to hospital. The guy lived. That's a sample size of 1, but it was enough to convince me utterly.

I agree with training for precision - I fully believe that speed-to-resuscitation is absolutely critical as a factor in surviveability. There, is however, as in other medical surviveability issues, a ''golden window' of opportunity. For a non-breathing diver, it's measured in seconds, not minutes.

Where and when you find the victim is an important consideration. I wouldn't risk getting bent to recover a corpse. Deep recoveries (assuming no overhead/deco) would really depend on whether I was immediately on the scene or not.

 

[tracydr]

My husband rescued a guy who had a heart attack and cardiac arrest during the fist class he worked as a Dive Master Candidate.
He went up quickly, too quickly for safety, from 60 feet. He did get a chamber ride, but it mostly a precaution.
The guy survived mentally intact, so I would say that was a success.

 

[Hickdive]

Safe ascent is more important than speedily getting somebody to the surface - they are already in a better position from assistance,slow or not

Being bent is generally fixable - being drowned isn't quite so "easy".

A controlled buoyant lift is the ideal that we should teach to but if all else fails and the rescuer's skills or training are insufficient then getting a live casualty to the surface quickly is a much better option than bringing a drowned person to the surface at 10m/min.

Remember that the undamaged survivability of a brain starved of oxygen is typically only 2-3mins. Ascending at the "correct rate" from just 20 metres would take two of those minutes.

---------- Post added January 15th, 2014 at 07:49 PM ----------

The level of diver we are discussing is Rescue Diver.

The OP is by a trainee currently taking the BSAC Ocean Diver course. That is the BSAC's entry-level course.

 

[dumpsterDiver]

For an emergency ascent, it makes a lot of sense to have the victim positive, you stay negative, hang on, remain still and ride them (slowly) to the surface. i know this is repetitious, but trying to kick a negative buddy to the surface is going to make it more likely that you will over dump and if you lose contact, they will sink and will almost surely be dead. I would like to keep the victim, just barely positive for the entire ascent.

In practice, it may be quicker and easier to kick a few cycles if you over-dumped their BC, rather than adding air on the ascent, but the preference would be to float up not kick. The rescuer is going to need all his energy on the surface. That is where it will be strenuous.

 

[TMHeimer]

I took Rescue years ago and believe I was taught to completely deflate the victim's BC and use your own. Since then I've read a lot of opinions on which way to go. Having air in 2 BCs doesn't seem too logical. Using the victim's BC seems not quite as simple. I would guess there are several ways to get the job done.

 

[PsyWulf]

Being bent is generally fixable - being drowned isn't quite so "easy".

A controlled buoyant lift is the ideal that we should teach to but if all else fails and the rescuer's skills or training are insufficient then getting a live casualty to the surface quickly is a much better option than bringing a drowned person to the surface at 10m/min.

Remember that the undamaged survivability of a brain starved of oxygen is typically only 2-3mins. Ascending at the "correct rate" from just 20 metres would take two of those minutes.

You misunderstand the premise of the post. You cannot know how long the diver has been down necessarily. In that instance and generally with a rescue the idea is to provide assistance without putting yourself at risk of severe injury. Your intervention - even after the 2minute mark is the difference between injury and death for the victim,already an improvement.

Sure the urge may be there to rush it,and if you can safely do it go for it. But don't rush for the sake of 'maybe' preventing brain damage.

Sent from my GT-P7500 using Tapatalk HD

 

[dumpsterDiver]

.... don't rush for the sake of 'maybe' preventing brain damage.

Sent from my GT-P7500 using Tapatalk HD

Yeah why hurry, there are many better reasons to rush things. Take your time, The diver can always get a transplant if things go south.

 

[danvolker]

I have to agree with DD.....
Training agencies like to make money with courses.....Rescue is no exception.....and yet, the liability issues they face has them "training" rescue divers to FAIL --if they utilize the SAFE ascent speed practices that TRAINING mandates. The agency is NOT going to be able to say that in your rescue of a non-breathing diver at 100 feet, that you need to get them to the surface in the next 20 seconds--even though this would be quite easy to do.....
So there are divers that are willing to rescue and place their own health in some risk....there are those willing to pretend to be trying to rescue, but that have full knowledge that their slow ascent may well destroy any chance the non-breathing diver has of resuscitation...and there are those that are happy to perform body recoveries.

I would say you need the knowledge and skills taught in a rescue course, and then you need to classify your own two types of rescues:
1.) Rescues where you will try to save the non-breathing diver that is a friend or loved one, where you are perfectly willing to ignore any DCS ramifications to reach the surface in seconds--hopefully to turn over the rescue to boat crew on the surface and go back down to bottom depth for quick deco , prior to leaving the water--and if not available, be willing to do the chamber ride if necessary....
2.) Rescues on people you don't know or care that much about, where you will do the rescue with the slow ascents as taight by the training agencies.