DAN America and DAN Europe Datad35gjurzz1vdcl.cloudfront.net/ftw-files/Day1/Evidence/2.pdf ·...
Transcript of DAN America and DAN Europe Datad35gjurzz1vdcl.cloudfront.net/ftw-files/Day1/Evidence/2.pdf ·...
Common Factors in DivingCommon Factors in Diving FatalitiesFatalities
DAN America and DAN Europe Data
Petar J. Denoble, MD., D.Sc.Alessandro Marroni, MD. D.Sc
Richard D. Vann, Ph.D.
Fatality Workshop, Durham April 8-10, 2010
1
SourcesSources
• DAN Insured Members Claims 2000‐2006DAN Insured Members Claims 2000 2006– 187 dive‐related deaths
• EDAN Insured Members Claims 1996 2008• EDAN Insured Members Claims 1996‐2008– 144 dive‐related deaths
• DAN Fatality & Injury Database 1992‐2003: – Most common causes of deaths; 947 cases in OC diving
– Case control study: 165 fatal and 135 non‐fatal AGE case
– Diabetes mellitus: 37 cases vs. 938 non DM cases
Annual numbers of diving fatalitiesAnnual numbers of diving fatalities
160 USA & C d
120
140
160
ths
USA & CanadaBSACAustraliaEDAN, insured
80
100
er o
f Dea
t
20
40
60
Num
be
0
20
1970
1972
1974
1976
1978
1980
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
2004
2006
2008
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2
Annual Number of Diving FatalitiesAnnual Number of Diving Fatalities
160
120
140
60
USA &
80
100
120
of D
eath
s
40
60
80
Num
ber
DAN
0
20
40 DAN
4
01970 1975 1980 1985 1990 1995 2000 2005
Study #2: Annual Fatality Rates of Insured DAN Members
• DAN diving accident insurance data, 2000‐2006
• 1,141,367 insured member years
• 187 diving related deaths• 187 diving related deaths
• Sex, age, cause of death
Individual Risk Per Annum (IRPA)Individual Risk Per Annum (IRPA)
• IRPA = Probability (individual is killed during oneIRPA Probability (individual is killed during one year of exposure)
• As safety performance measure:
Observed number of fatalities
IRPA = ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐
Total number of person‐years exposed
DAN Membership IRPADAN Membership IRPA
187
63 * 0 6IRPA = ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ = 163 * 10‐6
1,141,367
1 in 6000 or 0 016%1 in 6000 or 0.016%
Individual Risk Per Annum (IRPA)Individual Risk Per Annum (IRPA)
Industry sector Annual risk Annual risk
Recreational diving* 1 in 6,000 163 x 10‐6
Jogging 1 in 7,700 130 x 10‐6
6Mining and quarrying 1 in 9,200 109 x 10‐6
Construction 1 in 17,000 59 x 10‐6
Agriculture, hunting 1 in 17,200 58 x 10‐6Agriculture, hunting 1 in 17,200 58 x 10
Fatalities to self‐employed 1 in 50,000 20 x 10‐6
Manufacturing industry 1 in 77,000 13 x 10‐6
Fatalities to employees 1 in 125,000 8 x 10‐6
Service industry 1 in 333,000 3 x 10‐6
Data from “Reducing risks, protecting people” (HSE 2001)* DAN membership data
BSAC & DAN Fatality Rates
50
60BSAC Fatality RateDAN Fatality Rate
y = -0.3456x + 704.87R2 = 0.1776 (p = 0.0016)40
50
Mem
bers
BSAC Fatality Rate Trendline
30
/ 100
,000
M
10
20
Dea
ths
0
10
9
Rate (95%CI)
Scuba injury death rates
Group Denominator Time periodRate (95%CI)
per 100,000 divers
per 100,000 dives
Cave Divers GB Measured 1957 1979 138Cave Divers, GB Measured 1957-1979 138Cave Divers, GB Measured 1980-2006 24.6USA Estimated 1986 3.4 to 4.2USA Estimated 1989 16.7 0.8 to 1.6Orkney, Scotland Measured 1999-2000 4Australia Estimated 1989 34 (1 in 3000) 1.7 to 3.4Victoria, Australia Tank fill count 1992-1996 2.5
SAustralia
Survey2000-2006 3.57 (1 in 28,000) 0.57
BC, Canada Tank fill count 1999-2000 2.04Japan Tank fill count (8 8-33 8) 1 0 to 2 4Japan (8.8 33.8) 1.0 to 2.4
BSAC Measured
2000-200614.4
(10.5-19.7)Measured 16.4 (1 in 6000)
DAN Insured 2000-2006 0.7*(14.2-18.9)
*estimated based on 25 dives/diver/year
Acceptable RiskAcceptable Risk
Activities with a fatality risk greater than 1 ∙10−3Activities with a fatality risk greater than 1 10deaths/year to the general public are generally not acceptablenot acceptable.– Cars 3 ∙ 10−3 deaths/person‐year
– Falls 1 ∙ 10−4 deaths/person‐year
Scuba diving 1.6*10-4/p y
– Fires 4 ∙ 10−5 deaths/person‐year
– Drowning 4 ∙ 10−5 deaths/person‐year
– Firearms 1 ∙ 10−5 deaths/person‐year
– Poisoning 1 ∙ 10−5 deaths/person‐year
– Lightning 8 ∙ 10−7 deaths/person‐year
Criteria for Acceptable Risk in the h l dNetherlands
Diving 1.6x10-4
J.K. Vrijlinga, P.H.A.J.M. van Geldera & S.J. OuwerkerkaDelft University of Technology
ALARPALARPALARPALARP
•• As Low As Reasonable Practicable (ALRAP)As Low As Reasonable Practicable (ALRAP)As Low As Reasonable Practicable (ALRAP)As Low As Reasonable Practicable (ALRAP)
1.0E-01 1/10
1.0E-03
sk (I
R)
Unacceptable region
The ALARPTolerable only if risk reduction Is impracticable or cost is grossly disproportionate to
1/1,0001/6,000
1/30 000
1 0E 07
1.0E-05
Indi
vidu
al r
is
Broadly acceptable region
grossly disproportionate tothe improvement gained 1/100,000
1/10 000 000
1/30,000
1.0E-09
1.0E-07Negligible risk
1/10,000,000
1/1,000,000,000
• 947 Open-Circuit Deaths from 1992-2003• 70% family interviews y
• 60% autopsy findings
• 52% witness reports p
• <52% investigative reports • 28% equipment testing28% equipment testing
• 22% breathing gas analysis
14
Cause of Death (DAN America n=814)(DAN America, n=814)
97% 99% 100%100%600
84%
97% 99% 100%
80%
400
500
70%
40%
60%
300
400
umul
ativ
e
requ
ency
20%
40%
100
200
CuFr
0%0
100
Cause of Death (EDAN n=112)(EDAN, n=112)
100%95%100 100%
100%99%
83%80
90
80%
70%
50
60
70
uenc
y 60%
ulat
ive
30
40
50
Freq
40% Cum
0
10
20
0%
20%
0Drowning Cardiac AGE Trauma Marine life
0%
Root Cause Analysis of Diving Deaths
TriggerFirst identified cause in the
chain
Example 1Out of Air
Example 2Entangled
chain
Harmful Agent/ActionI di t f di bli EmergencyImmediate cause of disabling
injuryEmergency
Ascent Out of Air
Disabling InjuryIncapacitates or kills diver Air
Embolism Asypxhia
Cause of Death (COD)
Embolism
Cause of Death (COD)Final cause of death as
specified by CoronerDrowned Drowned
Root Causes
Causes Frequency
Role
Disabling TriggerAgent Trigger
Complication of a pre-existing disease 389 169 24
Buoyancy 293 43 18
Emergency ascent 289 187
Water movements 217 31
Gas supply problem 199 62 145
Equipment problem 109 6 56
Entrapment/Entanglement 75 61 68Entrapment/Entanglement 75 61 68
Injury 40 38 26
Wrong gas 14 8
Lost/separated 13 13Lost/separated 13 13
Total N/A 574 381
Triggers (n=346)
92% 98% 100%100%150
60%
76%85%
92%
60%
80%
100
ulat
ive
uenc
y
41%
60%
20%
40%50 C
umu
Freq
u
0%
20%
0
21
Disabling Agents (n=332)Disabling Agents (n=332)
94% 98% 100%100%200
60%
80%
94% 98%
60%
80%150
tive
ncy
60%
40%
50
100
Cum
ulat
Freq
uen
0%
20%
0
50
22
Disabling Injuries (n=590)
93% 96% 98% 100%100%200
yjury
62%
88% 93%
60%
80%150
blin
g In
jury
sabl
ing
Inj
33%
62%
40%
50
100
lativ
e D
isab
ency
of D
is
33%
0%
20%
0
50
Cum
ul
Freq
u
Triggers by Disabling Injury
Disabling Injuries
Trigger Asphyxia AGE CardiacTrigger Asphyxia AGE Cardiac
Insufficient gas 32% 63%
Entrapment 40% 9% REntrapment 40% 9%
Equipment trouble 15% 17%
Rough water 11%
Rarely Rough water 11% identiified
Disabling Agent by Disabling Injury
Primary Disabling Injuries
Disabling Agent Asphyxia AGE CardiacDisabling Agent Asphyxia AGE Cardiac
Emergency ascent 13% 97%
Insufficient gas 62% RInsufficient gas 62%
Buoyancy trouble 17%
Rough water 11%
Rarely Rough water 11% identiffied
Odds Ratios for Root Causes & I t i i F t& Intrinsic Factors
Asphyxia AGE Cardiacp yEntrapment ≥30Emergency ascent ≥30Emergency ascent ≥30Cardiovascular Disease ≥30Insufficient gas 16Insufficient gas 16Age > 40 years 6Equipment trouble 5Equipment trouble 5Rough water 4Female 2Female 2Depth < 80 fsw 2
Cardiac Incidents (n=156)
• Body Mass Indexy– Cardiac incidents: 30.5 kg/m2
– AGE: 28 7AGE: 28.7
– Asphyxia: 27.8
• 60% of victims of cardiac incidents noted• 60% of victims of cardiac incidents noted dyspnea, fatigue, distress, chest pain, or felt ill
56% h d & ll id f• 56% had autopsy reports & usually evidence of CVD but not myocardial damage
Case Control Study: Risk Factors for Fatal & Non‐Fatal AGE, 2005
• What factors influence the risk of death?• What factors influence the risk of death?– Demographic
E i– Experience
– Medical history
– Dive profile
– Dive conditions
– Dive problems
28
Buoyancy Trouble & Non‐Fatal AGEy y
10,928 i h10,928 i h
127i h AGE127i h AGE without AGEwithout AGE
7 with
with AGEwith AGE
69 withbuoyancy69 withbuoyancy
buoyancy trouble
buoyancytroublebuoyancytroubleOdds of buoyancy
trouble with AGE= 7/(127‐7) = 0.06
Odds of buoyancy
trouble without AGE
= 69/(10,928‐69) = 0.0064
/( )
Odds Ratio (OR) of non‐fatal AGE
for divers with buoyancy trouble
29
for divers with buoyancy trouble
= 0.06/0.0064 = 9.2
AGE FindingsAGE Findings
• ~12% of all injuries were fatal12% of all injuries were fatal
• ~6% of non‐fatal injuries were AGE
O h lf f ll AGE f t l• Over half of all AGE were fatal
• Sex, CVD, diabetes & asthma not AGE risk factors
• Greater AGE risk for divers in 1st year of ycertification & on 1st dive of day
30
AGE FindingsAGE Findings
• AGE risk decreases with experience p
• Dive problems appear strong risk factors although diagnostic bias is a problemalthough diagnostic bias is a problem– Rapid ascent, gas supply, buoyancy
• Factors associated with AGE death• Factors associated with AGE death– Higher risk: obesity, increasing age, use of helium increasing maximum depthhelium, increasing maximum depth
– Lower risk: healthy BMI
31
Pulmonary Barotrauma in Divers During EmergencyFree Ascent Training: Review of 124 CasesFree Ascent Training: Review of 124 Cases
Pierre Lafère , Peter Germonpré ,and Costantino Balestra
• Risk of PBT during training dives 100‐400 x
• During ascent training dives 500‐1500x
• Most Belgian sport diver federations have modified their ascent training protocols since 2006– Since then, no cases of PBT related to ascent training
Aviat Space Environ Med 2009; 80: 371 – 5 .
Diabetes & Fatalities
• Review DAN Fatality Database 1992‐2004• Total 975 fatalities
– 938 Non‐DM (96.2%)
– 37 with DM (3.8%)
• Variables: divers characteristic, accident scenario, , ,disabling conditions
• Age and dive depth tested with t‐test for independent g p psamples
• Contrasts tested with Chi squared analysis• Significance accepted at p<0.05
Adverse Events Preceding DeathsAdverse Events Preceding Deaths
C diti% of Decedents
St ti tiCondition StatisticsDM Non-DM
Cardiac 40.5 15.9 p<0.001Unknown 27.0 37.8 NSAGE 10.8 17.9 NSD i 10 8 20 5 NSDrowning 10.8 20.5 NSUnexplained LOC* 10.8 1.3 p<0.001Trauma 0 3 5 NSTrauma 0 3.5 NSDCS 0 1.8 NSWrong gas 0 1.3 NS
* loss of consciousness
Mean AgeDAN Members and Fatalities
50 Fatalities
y = 0 702x + 38 47rs)
Fatalities
DAN Members
y = 0.702x + 38.47R² = 0.838
40ge (Y
ear
y = 0.3287x + 36.53R² = 0.7475
Mea
n A
g
30
M
1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003Calendar Year
DAN Fatality Rates by Age DAN Fatality Rates by Age
35
40
25
30
35
iver
s *
20
25
00,0
00 D
Males*
10
15
Per
10
Females* * *
0
5
36
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70Age (years)
EDAN Insured Members200,000 insured years, 141 deaths
300
350
divers
63,000 Females137,000 Males
RR 0.2-10 (NS)
200
250
er 100,000
d
RR 0.6-12 (NS)
100
150
ity rates pe
RR 0.6-3.6 (NS)RR 1.9-9.9
0
50
<20 20-29 30-39 40-49 50-59 60+
Fatali
Age
Age & Cause Specific Relative Risk Age & Cause Specific Relative Risk
Disabling Injury
<50 yearsn=788 489
≥50 yearsn=352 878 RRInjury n=788,489 n=352,878 RR
Cardiac 5* 29 12.9
AGE 8 14 3.9
Asphyxia 15 17 2 5Asphyxia 15 17 2.5
Total 50 79 3.5
* Number of deaths
Conclusions
• Death while diving by insured DAN members occurs f 1 i 6000 diat rate of 1 in 6000 divers per year.
• Most common causes are gas supply problems, emergency ascent, cardiac health issues, entrapment/entanglement and buoyancy issuesentrapment/entanglement, and buoyancy issues.
Ri k f d th hil di i i ith• Risk of death while diving increases with age.