Recreational Scuba Diving Fatalities by the Numbers

Transcription

1 Recreational Scuba Diving Fatalities by the Numbers Petar J. Denoble, MD., D.Sc. RF3.0 Orlando, May

2 Hazards Risks Rates

3 Hazard Anything that has the potential to cause material damage or personal injury/illness.

4 Examples of Hazards and Their Effects Source Example of Hazard Example of Harm Caused SCUBA Loss of gas supply Asphyxia, drowning Hyperbaric gases Liquid environment Changes in environmental pressure Hypoventilation due to increased gas density Loss of buoyancy control Rapid decompression DCS CO 2 intoxication Sinking (drowning), uncontrolled ascent (AGE, DCS) Dangerous marine life Shark attack Bites, bleeding to death Practice Wreck diving, entanglement Drowning

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8 Risks Probability that damage or injury will occur.

9 Pyramide of Outcomes How often mishaps happen? Incidence of mishaps What fraction of mishaps result with injury? Morbidity of mishaps What percentage of injuries result with death? Mortality of injuries

10 Mishaps are Quite Common Sample: SSAC members dives, representing 148 years of diving experience. SHARED ASCENTS 1/173.8 dives RESCUE OF DIVER STARTING UNDERWATER 1/187.0 dives (including ascents in which rescuee did not use own main air supply) RESCUE OF DIVER STARTING ON SURFACE 1/202.0 dives FAILURE OF AIR SUPPLY 1/206.7 dives FREE ASCENTS 1/243.4 dives CONTAMINATED AIR SUPPLY 1/270.2 dives ABLJ ASCENT USED 1/486.8 dives OCTOPUS ASCENT USED 1/486.8 dives HYPOTHERMIA 1/811.3 dives ILLNESS NOT CAUSED BY DIVING BUT MANIFESTING ITSELF UNEXPECTEDLY DURING DIVE 1/ dives DECOMPRESSION SICKNESS 1/170,000* dives Curtis ASG. A view from the Scottish Sub-Aqua Club. SPUMS 1978;8(2).

11 Gareth Lock: The Incident Pit Organisational Influences Unsafe Supervision Pre-condition for Unsafe Acts Unsafe Acts / Active Failures Gareth Lock Accident / Incident

12 Fatalities are Few Annual Numbers of Diving Fatalities Number of Deaths USA & Canada BSAC Australia EDAN, insured

13 Fatality Rates Per capita rate number of deaths per given number of participants, per given period of time Per exposure rate number of deaths per number of dives

14 Denominators and exposures Source * Annual average Denominator (n divers ) Exposure (n dives/diver/year) BSAC* 38, DAN insured* 144, US Census ,558,000 4 Sport Goods Manufacturers Association ,732, ,847,000 < 8 386, ,

15 Fatality Rates Source Rate per 100,000 dives Rate per 100,000 participants/year PADI, trainees 0.49 N/A USA Census * 3.6* BSAC 0.54* 14.4 DAN America 0.7* 16.4 DAN Europe 1.4* 70 BC, Canada 2.04 N/A Orkney, Scotland 4 N/A * estimate

16 Rates of Injury and Death Vary Divers Skills, fitness, health, age, culture Environment Depth, wrecks, caves, cold, current, visibility Equipment Open closed circuit; tethered untethered diving Organization Solo, guided, expedition

17 DAN Fatality Rates by Age Per 100,000 Divers * * Males * * * Females Age (years) 18

18 Triggers Disabling Injuries Cause of Death

19 Investigation - Drowning Vasily Grigorevich Perov ( ), Deutsch: Tretjakow-Galerie. The York Project. Wikipedia.

20 An Abridged Root Cause Analysis Trigger First identified cause in the chain Example 1 Out of Air Example 2 Entangled Harmful Agent/Action Immediate cause of disabling injury Emergency Ascent Out of Air Disabling Injury Incapacitates or kills diver Air Embolism Asypxhia Cause of Death (COD) Final cause of death as specified by Coroner Drowned Drowned

21 Bears, deers or hares?

22 Triggers (n=346) Frequency % 60% 76% 85% 92% 98% 100% 100% 80% 60% 40% Cumulative 20% 0 0% 23

23 Disabling Injuries (n=590) Frequency of Disabling Injury % 62% 88% 93% 96% 98% 100% 100% 80% 60% 40% 20% 0% Cumulative Disabling Injury

24 Sudden Cardiac Death Dive Related or Not? Diving fatalities 25% DRiving fatalities 1%

25 Mean Age DAN Members and Fatalities 50 Fatalities DAN Members Mean Age (Years) Calendar Year

26 Cause-Specific Relative Risk and Age Disabling Injury Number of Deaths <50 years 50 years RR n=788,489 n=352,878 Cardiac AGE Asphyxia Total

27 Hazards Cave Diving No free surface overhead, long penetrations Risks Number of Deaths 18 Trained 16 Untrained fyear

28 Hazards Rebreather Diving CCR failure Human-machine interface problems Extended range diving Risks Frequency

29 Comparison of Triggers Insufficient Gas Lost/Entrapment Equipment Operating Issues Open Circuit Cave CCR 30

30 Comparison of Disabling Injuries 100 Cave diving Open scuba Rebreathers Percentage Drowning AGE Cardiac Inappropriate Gas Hypoxia CO 2 Seizure 31

31 Simple-minded Conclusions Hazards in diving are many, mishaps are common but the risk of dying is small ( The death is forever) Most mishaps (and scuba deaths) are preventable. Check-list them out! Death due to health issues may not be predictable but it is preventable. Watch your health!

32 Entrance to the Blue Cave, Island of Bishevo, Croatia