Your reaction to this emergency situation.

[DevonDiver]

I find it interesting that no one has mentioned dropping the diver's weights, neither at depth nor at the surface.

Yep, I left that wrapped up in the 'surface rescue' side of it also ("as per rescue course"). I wouldn't drop the weights at depth, as I'd want to control the ascent rate.

 

[tadawson]

As per my recent rescue cert, I'd follow to a depth that I was safe at (the "no second victim thing again") and arrest the descent. If at or near the bottom, put the victim on the bottom momentarily and make a quick assessment (if not, do it in the water column after making them neutral): Water in mask? Yes - it comes off, no - it stays on. Reg in mouth? Yes - it stays, no - it stays out. Review gear/buckles to determine how to ditch, and assess weight release. My right arm under the vitims right arm, hand holds reg in if present. Left hand gets victims BC which is used to control the ascent. Swim them up at 30ft/min (normal rate) but skip the stop. At surface, make victim positive (drop weights if needed, not mandatory), assess breathing, if none, start mouth to mouth in water - ditch mask on victim. Once cycle is going, ditch own gear and release victims gear down to cumberbun (spell?) only. Tow if needed with left had over head by jaw (also protecting airway), right hand stripping gear, supporting neck, as needed while swimming, while maintaining breathing to shore/boat/whatever, and signal ASAP as to the need for help. At extraction point, drop victims gear completely (it'll float), and handle extraction. After the victim is clear, secure the victims gear for possible investigation.

I would *NOT* exceed ascent rate and put either of us at risk. Pulmonary embolism is also quite fatal, so to fast of an ascent with an unconscious diver aggravates that risk. As far as how deep I would go, I guess that depends on the chance to catch the person, personal involvements, if the bottom is near, etc.

- Tim

 

[DevonDiver]

Swim them up at 30ft/min (normal rate) but skip the stop....I would *NOT* exceed ascent rate and put either of us at risk.

Just wondering why you'd use such a conservative ascent rate? PADI train for ascent at 18m/60ft per min - given that time is the most critical factor... why double the ascent time from what you 'could' achieve?

From 100ft... your ascent at 30' per minute (>3 min ascent time) is going to severely degrade the potential survival of a non-breathing victim. .

60ft per minute may not be 'ideal' for general diving, but it's statistically proven to be 'safe enough' for recreational level diving. You'd certainly be doing this speed to save yourself - for instance, a CESA. At the start of a dive - first dive of the day - I'd suggest that an even quicker speed could be used, without a high probability of DCS. Even then, the DCS would most likely be minor, not debilitating, and easy to resolve with appropriate treatment.

Thousands of novice divers have ascent problems every day - exceeding their max ascent rate to the surface through inattention or uncontrolled buoyancy - and the vast majority of them escape without DCI symptoms. When symptoms do present in a tiny minority of those divers, they are rarely serious enough to cause death or any significant injury. Many of those cases are not severe enough to prompt the diver to seek immediate medical attention. Many of those resolve without treatment. When treated promptly, most make an immediate or swift recovery. The 'odds' are well stacked in the divers favour. If there was ever a time to conduct a 'fast' ascent - it'd be when someone else's life was slipping through your fingers with every second that ticked by...

Even if disinclined to take that personal risk, it's acceptable to bear in mind that pressure gradient is what dictates bubble formation. As you get shallower, the pressure change get greater. You'd be riding the right side of the 'off-gassing line' if you did a more rapid ascent at depth, becoming progressively slower as your depth decreased... slowing to your 30ft/min rate by the time you get to 30ft depth. There are some benefits to getting them shallower, quicker. For instance, you might encounter other divers, who can be alerted to assist you.

You also mentioned doing a 'swimming' ascent. Is that a direct preference over conducting a 'controlled buoyancy ascent'? (i.e. bring the casualty up using the buoyancy of their/your BCD). If so, why?

 

[dumpsterDiver]

Interesting scenario, but if you are shooting down a wall after someone, it would be very hard to keep track of the depth. The danger would be perceptual narrowing and setting a goal.... i.e., I WILL catch them. With that attitude and swimming like a nut, I can descend very fast, over 150 feet per minute. So you would need to catch them fast or you would be deep. If it happened at the beginning of the dive, I would chase them deep, at least to 250.

Once you caught the person, the last thing you would want to do is swim them up. Your legs will be tired and your head would be spinning. You would want to rest and collect your thoughts and for this I would add a bunch of air to their BC and ride them up fast... Probably 100 feet per minute or faster.

 

[1thumper]

A Rescue Course is a great way to increase your skills to handle such cases. However, it does teach the concept of "no second victim" which I think is much too unilateral; but understand that their lawyers will never let them teach people that it is ok to take an abnormal risk.

I'd probably go after the person in this case, and get them to the surface ASAP, and I would accept being outside the acceptable standard safety limits, even though I am rescue-certified and "should know better".

If I saw a toddler who had wandered into a street full of fast-moving cars, I'd probably risk being a "second victim" there as well to try to save the kid. Not right, not wrong, just my choice. No desire to be a hero but doing what I'd hope someone else would do for my my kid.

 

[ferris213]

A quick question relating to the narcosis issue. I have been to a max depth of 30m (100') and did not feel that I was affected by narcosis at all. I realise I probably was and just couldn't tell, but in the case of chasing down a sinking buddy, could you expect to get a sense of "I'm getting badly narced and am about to lose the ability to make decisions" or would you just happily keep swimming to your demise?

Is it something you can feel coming, and manage? Or will you be oblivious to it by the time it's too late?

 

[Thalassamania]

Catch them, stop their descent Conduct an immediate ascent (18m/60ft per min) with no stop. If regulator is in, keep it in. If out, forget it. Support their head, keeping their airway open/head horizontal. Use their BCD for buoyancy if it worked, if not, use mine. On the surface, raise alarm. Check breathing. Get them out of the water as quickly as possible, providing rescue breaths if the situation dictates that (as per rescue course).

I wouldn't hesitate to go deeper to collect them.
I wouldn't hesitate to ascend at a max safe speed - DCS can be mended, dead cannot.

What he said!

 

[fisheater]

Please remember that the "second victim" admonition isn't just to protect the would-be rescuer. It's ALSO for the primary victim, as further rescue attempts would then be faced with twice the number of victims and likely more than double the challenges.

 

[tadawson]

Well, not to sound too much like a tool, but because that is what NAUI taught in my cert, and to freelance and do otherwise could make me liable . . .

The ascent rate was stressed to be 30 ft/min, more to protect yourself than anything else, I believe. I tended to want to go a bit faster, and got called on it every time . . .

As far as the swimming ascent, to me, that one is simple - more control. You handle the victims BC to keep more or less neutral, and swim up. If you go positive, it's a lot easier to have the victim take off like a torpedo if you for some reason have to let go, and that ain't good . . . . Frankly, I don't think it would matter which you choose if you can control it . . . we were taught to swim up, and that's the way I normally ascend anyhow, so didn't really take any issue to that . . .

Frankly, one of the biggest things stressed in my rescue class was don't rush!

And I hear you about conservatism these days . . . I certed initially in 1979 (computer? That's a big, hot thing in a very large room . . . . divers? We have the US Navy tables . . . ) and the tables now have about half the NDL we used to use, and the 30ft/min is painful compared to what I used to be used to . . . But magically, we didn't get bent back then either . . . I think this is what you get when the certifying agency let's their legal department/risk management group write the specs . . . likely more to keep them from getting sued than the "best" solution for us . . .

But I digress . . .

- Tim

Just wondering why you'd use such a conservative ascent rate? PADI train for ascent at 18m/60ft per min - given that time is the most critical factor... why double the ascent time from what you 'could' achieve?

From 100ft... your ascent at 30' per minute (>3 min ascent time) is going to severely degrade the potential survival of a non-breathing victim. .

60ft per minute may not be 'ideal' for general diving, but it's statistically proven to be 'safe enough' for recreational level diving. You'd certainly be doing this speed to save yourself - for instance, a CESA. At the start of a dive - first dive of the day - I'd suggest that an even quicker speed could be used, without a high probability of DCS. Even then, the DCS would most likely be minor, not debilitating, and easy to resolve with appropriate treatment.

Thousands of novice divers have ascent problems every day - exceeding their max ascent rate to the surface through inattention or uncontrolled buoyancy - and the vast majority of them escape without DCI symptoms. When symptoms do present in a tiny minority of those divers, they are rarely serious enough to cause death or any significant injury. Many of those cases are not severe enough to prompt the diver to seek immediate medical attention. Many of those resolve without treatment. When treated promptly, most make an immediate or swift recovery. The 'odds' are well stacked in the divers favour. If there was ever a time to conduct a 'fast' ascent - it'd be when someone else's life was slipping through your fingers with every second that ticked by...

Even if disinclined to take that personal risk, it's acceptable to bear in mind that pressure gradient is what dictates bubble formation. As you get shallower, the pressure change get greater. You'd be riding the right side of the 'off-gassing line' if you did a more rapid ascent at depth, becoming progressively slower as your depth decreased... slowing to your 30ft/min rate by the time you get to 30ft depth. There are some benefits to getting them shallower, quicker. For instance, you might encounter other divers, who can be alerted to assist you.

You also mentioned doing a 'swimming' ascent. Is that a direct preference over conducting a 'controlled buoyancy ascent'? (i.e. bring the casualty up using the buoyancy of their/your BCD). If so, why?

 

[tadawson]

I didn't imply to leave them brick heavy - go for neutral. As I said to DevonDiver, I prefer neutral with a little finning to ascend - easier to keep the rate from getting out of hand that way . . . and really not much work. Also, that was our training in rescue . . .

- Tim

Once you caught the person, the last thing you would want to do is swim them up. Your legs will be tired and your head would be spinning. You would want to rest and collect your thoughts and for this I would add a bunch of air to their BC and ride them up fast... Probably 100 feet per minute or faster.