BSAC Dive Leader Training

1. BSAC Dive Leader Training Oxygen Administration in Practice

2. Lesson Outline • Types of casualties • Practicalities of oxygen administration • Administering oxygen to a casualty • Related considerations • Safety precautions • Limitations

3. Casualties • Incident statistics show that the majority of casualties will be • Breathing • Conscious • Suffering from decompression illness • Will need the use of a demand valve and oro-nasal mask for maximum oxygen concentration Incidence of casualties requiring basic life support is much lower

4. Posture • For decompression illness or burst lung, lay casualty flat on back • If decompression illness or burst lung is not involved • Legs may be raised to counter shock • Monitor for signs of adverse impact on casualty’s breathing

5. Administering Oxygen (1) • Start at the earliest opportunity • Greater nitrogen pressure gradient • Earliest reduction in tissue hypoxia • Don’t ration oxygen • Tender loving care (TLC) • For a second casualty • Use second demand valve and oro-nasal mask, if available • Otherwise use a pocket mask • Accept faster consumption of oxygen

6. Administering Oxygen (2) • Be prepared for a possible transient worsening of casualty’s condition • Initial reaction of brain to increased oxygen • Oxygen diffusing into bubbles • Oxygen toxicity • Not a problem at surface pressure / durations involved • Casualties of underwater O2 toxicity? – administer O2 on surface once any signs or symptoms have disappeared • No pain killers

7. Administering Fluids • Counter dehydration with fluids • Still isotonic drinks best, or water/squash • Do not administer caffeinated or fizzy drinks • Small amounts, at a rate of approx 1 litre/hour • Do not allow to interfere with or delay • Administration of oxygen • Evacuation to a recompression facility • Do not administer fluids if • Casualty is likely to vomit • Casualty is likely to inhale fluid • A general anaesthetic may be required • If no oxygen, fluids alone are beneficial

8. Evacuation • Don’t delay call to emergency services • At sea: Coastguard, VHF channel 16 • On land (DCI): BHA / RN Diver Helplines • On land (other): Ambulance/Police/Coastguard • DCI • Irrespective of any apparent improvement, casualty must get medical attention • Casualty’s buddy? • All relevant information must accompany any casualty

9. Oxygen Supply Exhausted? • Closed Circuit Rebreather • Can be set to deliver 100% oxygen • Nitrox • Open Circuit or Semi Closed Circuit Rebreather • Reduces the amount of inspired nitrogen • Not as effective as 100% oxygen but better than breathing air • Common considerations • Mouthpiece may not be tolerated • Oxygen % reduced by air inspired via nose

10. Missed Decompression • If a diver misses decompression stops for any reason, or is subject to a rapid ascent such that it is considered that they may suffer decompression illness as a result: • Do not wait for signs/symptoms to appear • Lay casualty down and keep quiet • Administer oxygen/fluids • Seek specialist medical advice on further action from the BHA / RN Diver Help lines

11. Entonox • Mixture of oxygen and nitrous oxide • Nitrous oxide is very soluble in blood • Large quantity of nitrous oxide passes into nitrogen bubbles to re-establish equilibrium • Causes size of bubbles to increase • Neveradminister to a casualty suffering from a diving accident Do not administer to a casualty of a non-diving accident if this follows diving Ensure emergency personnel fully understand - Do this tactfully!

12. Safety considerations • Beware of enclosed spaces!! • Avoid sources of combustion!!

13. Limitations • Oxygen is possibly prejudicial to some people • These people would be precluded from diving • Therefore only administer oxygen to divers known to be suffering from a diving-related problem • Above all remember • Oxygen is only a first aid treatment • Irrespective of any apparent improvement in the casualty’s condition, oxygen administration should always be accompanied by evacuation to a recompression facility

14. Summary • Casualties • Posture • Early administration of oxygen • Fluid administration • Evacuation • Missed decompression • Entonox • Safety precautions • Oxygen only for divers suffering from a diving-related condition