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Shallow Water Blackout - systems for saving lives - even in Unattended Mode


Although the problem of Shallow Water Blackout was a mystery at one time, I believe I may have found a cure or a prevention system which should work. The idea is to use an ear-oximeter to detect low blood oxygen levels and to trigger an alarm. This system is mentioned in the page about Shallow Water Blackout and works to get people rescued from situations where they have fainted underwater. The basic system works in "attended mode" where there's someone on-hand to fish the person out of the water and to resuscitate them. However, as I often have to face up to saving myself from deadly problems alone, for example diabetic hypoglycaemia, I have figured a variant of the Shallow Water Blackout alarm system which can even work in Unattended Mode!

Bearing in mind that a smoke alarm can save a person from fire even if they live alone and are asleep, and a carbon monoxide detector works and can save lives even if there are no gas engineers on hand to declare a gas boiler "condemned", it seems reasonable to have the Shallow Water Blackout salvation device configurable so that it can save life even if the person who has fainted underwater is alone. So, here's what happens next, in Unattended Mode:

After the ear-oximeter has detected a low blood oxygen level and has triggered the alarm, if no-one presses "reset" within a required number of seconds, the device goes into automatic rescue mode. The next piece of equipment to be set off is a floatation device. I have ideas for this being a miniature version of a car airbag, powered by compressed air, but carried inside a ring which in its unexpanded form is like those punk studded cat-collars. Once triggered, the ring expands outwards while maintaining the same internal diameter and then forms a floatation ring with a litre or two of air, round the neck.

A more oldfashioned piece of kit to do the floatation is a lifejacket, as seen on aircraft. I am not so keen on this, but it's an option. Different people have different preferences. Either way, the floatation device is triggered, and the body is brought to the surface, such that the head is above the water.

As with an epirb*, sensing being in water or out of water, the next level of the procedure is initiated. However, an epirb is triggered on entering the water. In contrast, this next event is triggered on reaching the surface.

It's all very well being floated, and having an alarm ringing, but still not breathing is a problem. So the next thing is, automatic resuscitation. This is something which not everyone would care to try, but I believe it is potentially a life-saving technique. If there's no-one around, and no-one responds to the alarm, the device delivers an electric shock! OUCH!

This is similar to the ideas suggested in some discussion about diving, where a diver who has become unconscious is revived by another diver who slaps the unconscious diver. Achieving the same effect in an unattended environment by electric shock may seem controversial, and also questionable as it involves electric shock in water. However, it's better than being left for dead, and it may result in the right reaction which is a coughing and spluttering response to get rid of the water in the lungs. It's important that this happens after reaching the surface, not underwater.


* epirb : Emergency Position Indicating Radio Beacons - nautical alarm systems which are triggered if they go in the water. See "epirb" in a search.

More about the problem of Shallow Water Blackout here.