Detection Of Drowning Victims


Published on

Author: Billy Doyle

Published in: Health & Medicine, Technology
1 Like
  • Be the first to comment

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide

Detection Of Drowning Victims

  1. 1. Detection of drowning victims- the foundation for SENTINEL A simulation study of surveillance efficacy- Summary of results Billy Doyle MS ,PG DipHsc, BHSc, EMT-P
  2. 2. Overview <ul><li>Project History </li></ul><ul><li>Literature search </li></ul><ul><li>Research overview and methods </li></ul><ul><li>Results of research (summary) </li></ul><ul><li>Discussion </li></ul><ul><li>Summary </li></ul>
  3. 3. ‘ wet chain of survival’
  4. 4. Project history
  5. 6. “ What do you think about ‘patrol support’ personnel conducting surveillance?- -could you do a study to see if this is safe? ”
  6. 8. Literature Search <ul><li>SO……… I searched far and wide….. </li></ul><ul><li>Key words- </li></ul><ul><li>drowning, detection, lifeguard, vigilance </li></ul><ul><li>Search limited to prospective and retrospective controlled studies, meta analysis, systematic reviews, & case controlled cohorts published 2000-2007 </li></ul>
  7. 9. 16
  8. 13. www. nothing. com
  9. 15. Literature Search <ul><li>SO……… I searched far and wide…..again </li></ul><ul><li>Key words- </li></ul><ul><li>drowning, detection, lifeguard, vigilance </li></ul><ul><li>Search limited to any type and publications of any date </li></ul>
  10. 16. Pia C.D.C Griffiths Fenner Ellis
  11. 17. Problem statement We really don't know how effective people are at detecting drowning behaviour.
  12. 20. Media comments.. <ul><li>“ I thought they were mucking around ” </li></ul><ul><li>S.Marwick; witness </li></ul><ul><li>“ ..if only help had been called for earlier..” Sgt.M.Breenan; NZ Police </li></ul><ul><li>“ ..Browns Bay beach is so safe… we can’t understand how someone can drown in front of dozens of people ..” Local business man </li></ul>
  13. 23. Drowning behaviour is complex … but predictable along a continuum [Its] detection is the function of cognition and like all aspects of human performance, is prone to error .
  14. 24. Research Question How would you measure the efficacy of detecting drowning behaviour?
  15. 25. Signal Detection Theory (SDT) <ul><li>Well validated (since 1950s) </li></ul><ul><li>Dynamic theory that allows for measurement of signal detection in highly complex situations </li></ul><ul><li>Ability to make comparisons from population to population </li></ul><ul><li>Forms basis science for other industries where vigilance and detection is important. </li></ul>
  16. 26. Study design <ul><li>21 lifeguard & 18 ‘patrol support’ candidates volunteered to participate in a surveillance simulation study </li></ul><ul><li>Both groups were instructed by the same instructor and received the same training </li></ul><ul><li>EXCEPT </li></ul><ul><li>‘ patrol support’ personnel did not undertake the water components of instruction or examination. </li></ul>
  17. 27. Study design cont. <ul><li>After the first study both groups received additional training. (45 minute video presentation and power-point presentation) </li></ul><ul><li>Both groups then repeated the simulation </li></ul><ul><li>Results were compared pre & post training </li></ul>
  18. 28. Data collection <ul><li>3 people withdrew from the study (lifeguard) leaving 18 people in both groups. </li></ul><ul><li>The primary outcome was the time taken to detect a simulated drowning patient after 45 minutes of scanning a simulated beach scene </li></ul><ul><li>Other data collected included; </li></ul><ul><ul><li>Age </li></ul></ul><ul><ul><li>Gender </li></ul></ul><ul><ul><li>Previous nights total sleep (normalized to 8hrs) </li></ul></ul><ul><ul><li>Relative humidity and room temperature </li></ul></ul>
  19. 29. Results - age
  20. 30. Sleep
  21. 31. Effect of sleep deficit <ul><li>If 8 hours is normal; any participant with >2 hrs of sleep deficit had slower detection times- </li></ul><ul><li>The effect was most severe in those <18 years </li></ul><ul><li>Sleep deficit had a larger effect on results than training, in those <18yrs. </li></ul>
  22. 32. Time to detect drowning behaviour- Pre-training comparison
  23. 33. Time to detect drowning behaviour- Post-training comparison
  24. 34. Discussion <ul><li>There are significant differences between the two groups detection times </li></ul><ul><li>It SEEMS this difference is smaller in older age groups </li></ul><ul><li>(25-35yrs) </li></ul><ul><li>Those aged ,16 years have slower detection times, regardless of group type </li></ul><ul><li>More research is needed to understand the reasons for this </li></ul>
  25. 35. Research conclusion <ul><li>Non-swimmers (trained) can detect drowning behaviour </li></ul><ul><li>Our research has identified they do this slower than traditionally trained lifeguards </li></ul><ul><li>Training will improve both groups performance </li></ul>
  26. 36. This raises the question……. Should we use non-swimmers in the role of surveillance in support of our current lifeguarding practices ?
  27. 37. Conclusion <ul><li>This study has been repeated twice- with similar results- it drove the invention of SENTINEL. </li></ul><ul><li>Our next project will involve conducting this research in the workplace . </li></ul><ul><li>It is our believe the way forward is through collaboration (Multi-centre trails). </li></ul>