1. JOINT SERVICE SUB AQUA DIVING
ILLNESS’ & TREATMENT
REVIEW

2. Objectives Revise Basic Life Support (BLS) skills
For diving incidents:
understand the conditions
recognise signs and symptoms
understand how oxygen administration benefits these conditions
Understand appropriate equipment and the practicalities of its use
Revise oxygen administration skills
breathing casualties
non-breathing casualties

3. Outline BLS In-Water Rescue Medical conditions Casualty Assessment
Oxygen administration equipment
Oxygen administration in practice

5. BASIC LIFE SUPPORT (BLS)

6. Lesson Outline BLS skills: Essential rescue skills
Deteriorate quickly if not frequently exercised
Advice/techniques evolve

7. Assessing the Need Indicators of the need for BLS: no response
no chest movement
no feel of air movement

8. D r A B C Priorities Danger – to casualty and rescuer Response (AVPU)
Airway
Breathing
Compressions

9. Head tilt/chin lift clears airway Airway blocked by tongue
Clear Airway
Foreign objects
Tongue
Head tilt/chin lift clears airway
Airway blocked by tongue

10. Priorities Danger – to casualty and rescuer Response
A – Alert
V – Responds to Voice
P – Responds to Pain
U – Unresponsive
Airway – clear of obstructions
Breathing – check for normal breathing (10 secs.)
Compressions – Cardiac Compressions

11. BLS: Decision Process Unresponsive Leave casualty and get help No Yes
Shout for help, open up airway
Breathing normally?
Leave casualty and get help,
return & give 30CCs No
Yes
Stop to recheck only if breathing resumes, else continue until:
Qualified help arrives
Normal breathing
You are exhausted
Recovery position

12. Basic Life Support
Sequence of 30 compressions: 2 breaths by one rescuer
Two rescuers: change role every 1-2 minutes
Monitor effectiveness
Stop if normal breathing resumes/medical assistance arrives

13. Basic Life Support - CC Place heel of hand in centre of chest
Place heel of other hand on top of first hand
Straight arms – press down on sternum 5-6 cm
Repeat at times/min

14. Basic Life Support - RB Expired air can sustain life
Monitor effectiveness
Don’t over
ventilate
Sight
Feel
Sound
Appearance
Continue until qualified help comes, the casualty is breathing normally or you are exhausted

15. Basic Life Support - RB Breaths are to be Regurgitation
No more than 1 second each
2 breaths to take no more than 5 seconds
Don’t attempt more than 2 breaths each cycle
Don’t over
ventilate
Regurgitation
Not always normal vomiting
Monitor exhalation sounds

16. Recovery Position If casualty breathing place in recovery position
The ‘how’ position
More stable position

18. IN-WATER RESCUE

19. In Water Life Support Sequence
Make Buoyant
Extend Airway
RB for 1 minute
Tow, RB - 2 every 15 secs.
Standing depth/Boat 1 min. RB
De-Kit & Land

20. Rescue - to the surface Diver out of gas Incapable/unconscious diver
AS Ascent
Incapable/unconscious diver
CBL
Rescue ascents - Urgent
Ascend directly to surface
May mean ignoring decompression stops
Divers safer at surface
DCI can be treated
Actions to take in case of oxygen convulsions
Controlled
Buoyant Lift
AS ascent

21. Surface Tows to Shore Summon help Conscious casualty
Ensure casualty buoyant at surface
Fully inflate BC - face clear of water Consider removing weights
Summon assistance
Conscious casualty
Reassure
Unconscious casualty
Remove mask, mouthpiece and extend airway
Non Breathing casualty
Remove mask, mouthpiece and give RB for 1 minute i.e. 10RBs

22. Landing Casualty - Shore
Standing depth
Continue RB for a further 1 minute
De-kit and land as quickly as possible WITHOUT further rescue breathing
Lift from water
Contact emergency services
Continue BLS

23. Landing Casualty - Boat
Assistance available
At boat prior to landing Continue RB for a further 1 minute
De-Kit and remove from water as quickly as possible WITHOUT further RB
Contact emergency services
Continue BLS

24. Effective Rescues Typical indications Concerns need to be resolved
Nervous or reluctant
Excuses or repeated questions
Stress indicators
Slow kit up or constant fiddling
Concerns need to be resolved
Adapt the dive plan
More suitable dive site
Peer pressure

25. Pre-Dive Buddy Awareness
Buddy reactions
Stopping for no reason
Preoccupation with kit
Slow response to signals
Rapid breathing
Wide staring eyes
Resolve quickly
Stop or move to buddy
OK? Problem?
Not OK, gentle but firm contact
Abort dive

27. MEDICAL CONDITIONS

28. Oxygen Exposure Oxygen Partial Pressure Scale (bar)
Hyperoxic
Oxygen Partial Pressure Scale (bar)
1.0 .5
.21
1.6
.16
.10
.08
1.4
Short term toxicity risk
Long term toxicity risk
Hypoxic
Unconsciousness
Abilities impaired
AIR
At high concentrations oxygen is toxic
PO2<0.16 bar does not support life
Need to remain within accepted oxygen exposure limits

29. Hypoxia What is it: Hypoxic Lack of oxygen PO2< 0.16 bar .21 .16
.10
.08
Hypoxic
Unconsciousness
Abilities impaired
AIR
What is it:
Lack of oxygen
PO2< 0.16 bar

30. Hypoxia Symptoms: Hypoxic
.21
.16
.10
.08
Hypoxic
Unconsciousness
Abilities impaired
AIR
Symptoms:
Inability to think clearly, confusion, sense of losing it
Loss of co-ordination
Unconsciousness, death
Primary danger is symptoms may be vague or absent
It can occur suddenly and without warning!

31. Hyperoxic What is it: There are two different effects of Hyperoxia:
1.0 .5
.21
1.6
1.4
Short term toxicity risk
Long term toxicity risk
AIR
What is it:
Too much oxygen
Oxygen becomes toxic at elevated partial pressures
There are two different effects of Hyperoxia:
Whole Body Oxygen Toxicity when PO2>0.5 bar for long periods
Central Nervous System (CNS) toxicity when PO2>1.4 bar for even short periods

32. Whole Body Toxicity Cause: long exposures to PO2>0.5 bar
Monitored to allow for recompression treatment
Physiological reactions including:
Inflammation in the lungs
Reduction in vital capacity
Congestion, oedema, bronchitis, swelling of alveolar walls, thickening of pulmonary arteries
Visual impairment
Symptoms:
Dry cough, discomfort in breathing cycle, increased breathing resistance, shortness of breath,
Severe pain, sub-sternal pain or burning
Temporary short sightedness (Hyperoxic Myopia)

33. CNS Toxicity Also known as Acute Oxygen Toxicity
Reaction to PO2 generally > 1.4 bar
Symptoms:
CON - Convulsions
V - Vision
E - Ears, hearing disturbances
N - Nausea
T - Twitching
I - Irritability
D - Dizziness
Until convulsions begin, minor symptoms:
Can occur in ANY order or combination
Increase in severity

34. CNS Toxicity Convulsions Tonic phase – do not assist
Muscles become tense
Casualty becomes rigid and holds breath
Clonic phase – do not assist
May occur seconds or minutes after the tonic phase
Casualty jerks violently (convulsion)
Depressive phase - assist
Casualty relaxes and is unconscious
Potential loss of mouthpiece
Loop flood – loss of buoyancy
Need for Basic Life Support?

35. CNS Toxicity Convulsions
Phases can occur on surface or after PO2 is reduced (‘Off effect’)
Progressive damage to nervous system with each successive convulsion

36. Hyperoxia Causes: Hyperoxic Inaccurate dive planning
1.0 .5
.21
1.6
1.4
Short term toxicity risk
Long term toxicity risk
AIR
Causes:
Inaccurate dive planning
Failure to analyse gas
Incorrect marking or fitting of cylinders

37. Hyperoxia Aggravating factors: Hyperoxic Actual PO2
1.0 .5
.21
1.6
1.4
Short term toxicity risk
Long term toxicity risk
AIR
Aggravating factors:
Actual PO2
Duration of exposure
Level of exertion
Cumulative O2 exposure

38. Hyperoxia Avoidance: Hyperoxic
1.0 .5
.21
1.6
1.4
Short term toxicity risk
Long term toxicity risk
AIR
Avoidance:
High PCO2 predisposes to oxygen toxicity
Accurately track your oxygen exposure

39. Monitoring Oxygen Exposure
CNS and Whole Body Toxicity need to be monitored separately
Data for both provided in BSAC Oxygen Toxicity Table
Dive planning software
Nitrox & mixed gas decompression computers

40. CO2 Hypercapnia What is it: Cause: Excess CO2 in the blood
High inspired PCO2
Poor ventilation of diver’s lungs at depth due to increased gas density
Absorbent material exhausted in rebreathers
Channelling in absorbent material rebreathers
CO2

41. CO2 Hypercapnia Symptoms
0.03 bar PCO2 doubles breathing rate (dyspnea)
0.06 bar PCO2 distress, confusion, lack of coordination
0.10 bar PCO2 severe mental impairment
0.12 bar PCO2 loss of consciousness, death
CO2

42. CO2 Hypercapnia Further impact Avoidance Resolution
Increases oxygen toxicity potential
Increases potential for DCI and narcosis
Avoidance
Meticulous preparation & monitoring of absorbent life - rebreathers
Avoiding over exertion
Resolution
Stop, slow down breathing rate, relax
Bail out to open circuit - rebreathers
CO2

43. Decompression illness
Causes
inadequate elimination of nitrogen from the body during ascent
Physical damage to the alveoli due to overpressure introduces bubbles of air (emboli) into the blood
Patent foramen ovale (PFO) allows bubbles to pass from venous to arterial circulation
Bubbles blocking blood flow
Bubbles in tissues compress blood vessels

44. Decompression illness
Signs and symptoms
Denial!
Itches, rashes
Numbness, tingling, joint pains
Vision disturbances
Dizziness, nausea, headaches, confusion
Weakness, paralysis, loss of bladder/bowel control
Shortness of breath
Shock, unconsciousness
Any abnormality after a dive
Signs and symptoms appear from seconds to many hours after surfacing

45. Decompression illness
On-site first aid
Lie casualty down flat
Keep casualty quiet
Administer 100% oxygen
Increased nitrogen pressure gradient
assists in nitrogen elimination from
bubbles in blood and tissue
The higher the percentage of oxygen the
more effective – whenever possible administer 100%
Improved oxygen supply to tissues where blood flow is reduced due to bubble blockage
Treat for shock
Evacuate to a recompression facility as soon
as possible

46. Burst Lung
Cause
Physical damage to lung tissue from over-extension due to over-pressurisation
Types
Bubbles between organs and tissues (emphysema)
Collapsed lung
(pneumothorax)
Both types can occur in isolation but are usually accompanied by air embolism

47. Burst Lung Signs and symptoms
chest discomfort/pain, bloody froth
shortness of breath
changes to vocal tone, crepitation
shock
unconsciousness, death
Signs and symptoms of burst lung are frequently accompanied by those for decompression illness

48. Burst Lung On-site first aid Lie casualty down Keep casualty quiet
Administer 100% oxygen
Assists in re-absorption of the
nitrogen content of air in
pneumothorax or emphysema
Offsets reduced effective lung
surface area for gas transfer
due to collapsed lung
Treat for shock
Evacuate to a recompression facility as soon as possible

49. Near Drowning Cause Signs and symptoms
Respiratory interruption due to fluid inhalation
Signs and symptoms
Circumstances
No breathing
Cyanosis – ashen grey / blue appearance
Weak or absent pulse

50. Near Drowning On-site first aid Rescue Breathing
Oxygen-enriched if possible
Concentration of oxygen reaching the casualty’s lungs during RBs is increased
Chest compressions if required
Recovery position
Evacuate to medical attention
Even if apparently fully recovered
Complications of secondary drowning

51. Shock Definition Present to a greater or lesser degree in all injuries
inadequate circulation leading to tissue damage due to inadequate oxygenation and waste removal
Present to a greater or lesser degree in all injuries
Mechanisms
reduced blood volume (bleeding, burns, oedema)
massive dilation of blood vessels (e.g. fainting)
inadequate cardiac output (e.g. heart attack)
allergic reaction to drugs, food or stings
removal from the water after prolonged immersion

52. Shock Signs and symptoms weakness, dizziness pallor, sweating
rapid pulse rate
rapid breathing, feeling breathless
unconsciousness

53. Shock On-site first aid Treat prime cause Reassure casualty (TLC)
Keep casualty quiet
Lay casualty down with legs raised
(not in the case of DCI or burst lung)
Keep warm and comfortable
Administer oxygen
Increased oxygen dissolved in the blood offsets effects of inadequate circulation
Monitor condition
Nothing by mouth (except for DCI)
Evacuate to medical attention

54. Shock Immersion shock Extreme form of blood vessel
dilation due to prolonged
immersion
Muscles relax due to water
supporting body weight
If removed from water upright, blood
can pool in lower limbs – potentially
fatal
Keep casualty horizontal at all times
Discourage any movement or activity by the casualty

55. Carbon Monoxide Poisoning
Cause
breathing gas contaminated with carbon monoxide
Effect
carbon monoxide combines about 200 times more readily with haemoglobin than does oxygen
interferes with the blood's ability to transport oxygen
may act as a cellular poison CO

56. Carbon Monoxide Poisoning
Signs and symptoms
headache
pale or greyish appearance
weakness
dizziness, nausea
tunnel vision
vomiting
rapid pulse
rapid breathing
coma
convulsions CO

58. CASUALTY ASSESSMENT

59. Incident Procedure - Front

60. Incident Procedure - Back

62. OXYGEN ADMINISTRATION IN PRACTICE

63. 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
Rescue Breaths is much lower

64. Administering Oxygen 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

65. Administering Oxygen
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

66. 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

67. Evacuation Don’t delay call to emergency services
Coastguard: VHF Channel 16
DDMO / BHA DCI Helplines:
England, Wales & N. Ireland:
Scotland:
On Land (other)
Ambulance/Police/Coastguard
Telephone: 999 or 112
DCI
Irrespective of any apparent improvement, casualty must get medical attention
Casualty’s buddy?
All relevant information must accompany any casualty

68. 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

69. 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 DDMO/ BHA Help lines

70. 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
Never administer 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!

71. Final Summary Signs & symptoms can be similar for different conditions
Knowledge of pre-incident history
helps
Oxygen administration & TLC
are beneficial to all diving
illnesses & incidents

72. ?