Drowning is not a helpful diagnosis written on the death certificate By Dr. CJ Brooks & J. Jenkins Survival Systems Ltd., Dartmouth, Nova Scotia, Canada International Association for Safety and Survival Training International Meeting Sydney, Nova Scotia 20 th May 2006

Introduction Death at sea until now has been accepted as an occupation hazard and fate. Herodotus first described death from hypothermia in the Persian/Greek war BC. James Lind described post-rescue collapse in Hutchinson’s To preserve the Health and Comfort of Seaman. James Currie also noted hypothermia and post rescue collapse in 1797.

20 th Century Drownings – Royal Navy sailors – British Merchant seaman –5000 German sailors

Talbot Committee ,000 – 30,000 officers and men of the Royal Navy died in the Second World War - One third killed in action - Two thirds died in the survival phase - Cause of death in the survival phase was drowning and cold water immersion

Research in the UK Commencement of a large series of physiological experiments and practical field trials. Key scientists were Hervey and Glaser, Keatinge, McCance and Pugh. Funding came from the MRC through the RNPRC. –McCance et al.The Hazards to Men in Ships Lost at Sea 1956 –Nicholl’s Textbook Survival at Sea 1960 –Keatinge’s Textbook Survival in Cold Water 1969 –Lee and Lee’s Textbook Safety and Survival at Sea 1971 –Smith’s Survival at Sea MRC Report 1976 CONCLUSION that everyone died from hypothermia

1981-The Immersion Incident 4 Stages (Golden and Hervey) –Initial response (Cold Shock) Kills within first 3-5 minutes –Short Term Response (Swimming failure and loss of manual dexterity) Kills within first 15 minutes –Hypothermia Kills after 30 minutes –Post Rescue Collapse Kills anytime during and after the rescue

“Cold Shock” (Tipton, 1989) Heart Beat (Beats. Min -1 ) Breathing Rate (Breaths. Min -1 ) Breathing Volume (Litres. Min -1 ) Pre-immersion st minute of immersion th minute of immersion

We are still not doing very well! At least 140,000 open water deaths each year (Golden & Tipton, 2002)

A Retrospective Analysis of Drownings Reported to the British Columbia Workers ’ Compensation Board 1976 – By: C.J. Brooks and K.A. Howard

No. Drowned / Accidents FishingLoggingMVAMisc.Total No. of Accidents No. Drowned

Loggers (22 accidents) Cold shock 1 Swimming failure 1 Hypothermia 1 Post-rescue collapse 1 Drowning/Injury/ Entrapment 9 Impossible to diagnose 9 Total 22 Re-examination Drowning = 20 (91%) Drowning/Injury/Entrapment= 2 (9%)

Basic Information 130 fishermen drowned in 89 accidents.

Determined Cause of Death Pre- Investigation Coroners and accident investigators classified deaths into three categories: 113 deaths (87.0%) were classified as “drowning” or “drowning/other” 15 deaths (11.5%) were classified as “hypothermia” or “drowning/hypothermia” 2 deaths (1.5%) were classified as cardiac event after immersion

Cause of Death after Reclassification 7 deaths (5.4%) were reclassified as cold shock 7 deaths (5.4%) were reclassified as swimming failure 7 deaths (5.4%) were reclassified as hypothermia 1 death (0.8%) was reclassified as post rescue collapse 1 death (0.8%) was reclassified as cardiac event after immersion 13 deaths (10.0%) were reclassified as drowning or drowning with other factors (i.e. entrapment) 94 deaths (72.2%) were not reclassified due to insufficient information

Water Temperatures Reported in 15 accidents Calculated in 67 accidents Estimated in 7 accidents Water temperatures ranged from 0ºC to 17.5ºC In seven cases water temperature was above 15ºC

A Review of the CG-15 Incident Action Reports How many incidents investigated by the British Coast Guard (MCA) are due to drowning, and what was the underlying cause of the drowning death?

Results in both studies were very similar Accident investigators, pathologists and coroners had: (a)little knowledge of cold water physiology (b)tended to work in isolation of each other There were many pages of technical information but only single sentences on the human factors and cause of death

Results cont’ Critical testimony that might lead to the underlying cause of drowning either was not asked, not recorded or simply glossed over with such words as “ drowning”, “drowning exposure”, “drowning/hypothermia”, or “undetermined” Critical physical and physiological information eg. swimming ability, water temperature, hospital admission, core temperature, wearing of flotation devices or survival suits was missing in nearly every case.

All their technical data was meticulously recorded But there was very little detail on the medical/human factors portion of the inquiry There was not enough information to determine the underlying cause of drowning in any of the UK cases and only 35 of the Canadian fishermen’s deaths.

Conclusions and Recommendations Accident investigation needs to be done as a team The team needs to know about cold water physiology and the requirement to take a good incident history A checklist has been developed to assist anyone involved in a drowning death (see Annex of paper) In Canada, we lectured to BC coroners and pathologists and to the UK gave a full confidential report to the MCA Only in the next analysis after more precise data is recorded will it be possible to determine the underlying causes of drowning