Oxygen: Why we need it on every Dive

Besides the obvious (that we need Oxygen to live and it is in the air that we all breathe, under water and above) why do we need to have Oxygen for every Dive we make.

Working in a country, like Cyprus, where the Diving Conditions are relatively easy and the rate of incident
are pretty low, can Dive Centres and Diving instructors be forgiven for not having emergency Oxygen with them on every Dive they make?

Before we go on to discuss this issue, have a read of this Article from DAN about a 14 year old boy who had a diving incident in Malaysia where no Emergency Oxygen was immediately available.

Oxygen Administration is the recommended first aid for the majority of Scuba Diving Incidents ranging from; Decompression Sickness & Arterial Gas Embolism (Decompression Illness) to Near Drowning. Research has shown that the earlier 100% Oxygen can be given to a patient to breathe, the less severe and damaging the Injuries are likely to be.

Of course, the first step is to Identify and recognise that there is a problem, so let's have a quick look at some of the signs and Symptoms that may indicate Oxygen is Needed.

Decompression sickness	Arterial Gas Embolism
Signs
Skin rash	Bloody froth from mouth or nose
Paralysis, muscle weakness	Paralysis or weakness
Difficulty in urinating	Convulsions
Confusion, personality changes, bizarre behaviour	Unconsciousness
Loss of memory, tremors	No breathing
Staggering	Death
Collapse or unconsciousness
Symptoms
Fatigue	Dizziness
Skin itch	Blurring of Vision
Pain in joints or muscles	Areas of decreased sensation
Dizziness, vertigo, ringing in the ears	Chest pain
Numbness, tingling and paralysis	Disorientation
Shortness of breath

Table above taken from wikipedia

There are no definitive tests or unique signs to confirm DCS "in the field" and many of the symptoms are similar to those of other illnesses but if you suspect a Diving Incident, your first step should be to administer Oxygen.

Why Oxygen?

Oxygen is a life sustaining, essential gas. Although it does become toxic under higher Partial Pressures (below 6metres underwater), it is required for life in normoxic levels.

In a diving injury, bubbles that can form on ascent can block the blood supply to the body tissues, leading to damage and/or obstructions to Gas Exchange ie Oxygen reaching the tissues.

We administer 100% Oxygen in any Diving incident because it allows a higher concentration of Oxygen to enter the body, altering the pressure gradient for gas exchange and facilitating Inert Gas (Nitrogen and Helium) removal. 

The Oxygen can also help to decrease the size of any bubbles that may have formed on ascent, Oxygenate the Hypoxic Tissues (ones that weren't getting enough Oxygen to survive), ease breathing and relieve Symptoms.

There are also results to suggest there is a lesser risk of residual symptoms after Hyperbaric Treatment when Oxygen is administered early because the increased levels of Oxygen have prevented further damage being caused to the tissues by bubbles and hypoxia.

So, as you can see, having a supply of emergency Oxygen should be on every pre dive safety check list. Every Dive Centre and Diving Instructor/guide should have a sufficient supply with them to ensure that they can administer Oxygen First Aid, if needed, as soon as possible. The supply should be sufficient to allow the patient to continue breathing 100% Oxygen until emergency assistance arrives or you can reach the nearest hyperbaric treatment centre.

There have been several instances where our emergency Oxygen has been used on Dive Boats because Divers do not have their own and while I do not know any divers or diving centre that would withhold Oxygen from someone who needs it, it isn't acceptable to rely on someone else to provide it.

If every Diver relies on another diver to supply Emergency Oxygen, there will come a time when there is none available!

So, when you plan your next dive trip, don't forget to make sure there will be Emergency Oxygen First Aid available on every boat, in every truck/vehicle and someone available who knows how to operate it. 

If in doubt about a Diving Emergency, you can call the Divers Alert Network Emergency International Helpline and they can assist you with the steps you need to take and to find the nearest treatment centre. Keep this number with your emergency Oxygen and take it on every dive.

DAN Emergency Helpline Number: +1-919-684-9111