Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers plot locations where AEDs could save more lives

03.05.2013
A new study has found that publicly registered AEDs in Toronto are not in the best positions to help victims of cardiac arrest
Prompt use of an automated external defibrillator, or AED, can greatly increase the survival rates of people who suffer a cardiac arrest.

Yet a new study has found that publicly registered AEDs in Toronto are not in the best positions to help victims of cardiac arrest. In fact, less than one in four of all cardiac arrests had an AED close by (within 100 metres is the required distance). The average distance to the nearest AED was closer to 300 meters.

Current guidelines suggest areas associated with the highest risk of cardiac arrest should be targeted for AED deployment, after they have been placed in obvious high-traffic areas such as transportation hubs or major sports venues. But it's not clear how to identify these "cardiac hot spots."

Researchers at the University of Toronto and St. Michael's Hospital have developed a new mathematical formula to optimize the placement of costly AEDs in areas where they could do the most good. Their results were published in the journal Circulation.

Timothy Chan, an engineering professor at the U of T's Faculty of Applied Science & Engineering, looked at the locations of all 1,310 public cardiac arrests in Toronto between December 2005 and July 2010 and the locations of all 1,699 AEDS registered with Toronto Emergency Medical Services.

He found that 304 cardiac arrests occurred within 100 metres of at least one AED (23 per cent). One hundred metres was chosen as the yardstick because it's the approximate distance a bystander could transport an AED in a 1.5-minute walk—the maximum recommended by the American Heart Association.

There were almost three times as many public cardiac arrests in downtown Toronto as the rest of the city – 3.5 per square kilometer per year vs. 0.4 – said Professor Chan, who worked on the study with Dr. Laurie Morrison of St. Michael's Hospital. Almost half of all downtown cardiac arrests were near an existing AED compared to only 17 per cent those outside of downtown.

Professor Chan then looked at the 1,006 cardiac arrests that did not take place near an AED. He said that be placing AEDs in the top 30 cardiac arrest "hot spots," they could have covered an additional 112 historical arrests, or 32 per cent. The average distance between a cardiac arrest and an AED would fall to 262 metres from 281 meters.
"Reducing the distance a bystander needs to travel by 20 metres or up to 40 meters in a roundtrip has the potential to save close to half a minute in response time," said Dr. Morrison, an emergency medicine specialist.

"If you have a cardiac arrest, every second counts. Out-of-hospital cardiac arrest kills an estimated 300,000 people in North America annually," she said. "Only five per cent of people who suffer out-of-hospital cardiac arrest survive to be discharged from hospital. The probability of survival decreases up to 10 per cent with each minute of delay between collapse and treatment."

Dr. Morrison heads Rescu, the largest research team of its kind in Canada dedicated to improving out-of-hospital resuscitation.

Professor Chan said his mathematical model is more accurate than a population-based model, in which AEDs are placed in areas of densest daytime population.

"Our optimization model should be viewed as a decision-support tool to help prioritize placement of AEDs, make efficient yse of public, donor or private funds directed toward public access defibrillator programs, and potentially maximize survival on the basis of geographic patterns of cardiac arrest," said Professor Chan. "Because AEDs are expensive and cannot be placed everywhere, our model allows a decision-maker to quantify the trade-off between the number of AEDS deployed and coverage."

While it was not part of the research paper, Professor Chan used his mathematical model to indicate the top 10 cardiac hot spots in Toronto not currently covered by AEDs:
Jarvis and Gerrard (nearby buildings include the Inglewood Arms, Jarvis George Cooperative Homes, Ryerson International Living Learning Center, residential homes)
Queen and Bay (Sheraton hotel, Nathan Philips Square, The Bay)
Jarvis and Dundas (Hilton hotel, co-op housing, residential)
Brimley and Progress (Scarborough Town Center)
Eglinton and Warden (shopping plaza, industrial buildings)
Wellington and Strachan (medical office building, residential)
Dundas and Spadina (Chinatown, shopping plaza)
Queen and Shelbourne (Moss Park, street-level commercial/retail)
Danforth and Pape (Toronto Public Library, street-level commercial/retail, Pape Station, residential)

Jarvis and Adelaide (Saint James Park, Holiday Inn)

About St. Michael's Hospital

St. Michael's Hospital provides compassionate care to all who enter its doors. The hospital also provides outstanding medical education to future health care professionals in more than 23 academic disciplines. Critical care and trauma, heart disease, neurosurgery, diabetes, cancer care, and care of the homeless are among the Hospital's recognized areas of expertise. Through the Keenan Research Centre and the Li Ka Shing International Healthcare Education Center, which make up the Li Ka Shing Knowledge Institute, research and education at St. Michael's Hospital are recognized and make an impact around the world. Founded in 1892, the hospital is fully affiliated with the University of Toronto.

About University of Toronto Engineering

Founded in 1873, U of T Engineering has approximately 5,200 undergraduate students, 1,950 graduate students and 240 faculty members. U of T Engineering is at the fore of innovation in engineering education and research and ranks first in Canada and among the top Engineering schools worldwide.

For more information or to interview, please contact:
Leslie Shepherd
Manager, Media Strategy
Phone: 416-864-6094
shepherdl@smh.ca
St. Michael's Hospital
Inspired Care. Inspiring Science.
http://www.stmichaelshospital.com
Follow us on Twitter: http://www.twitter.com/stmikeshospital

Terry Lavender
Communications & Media Relations Strategist
Faculty of Applied Science & Engineering, University of Toronto
Phone: 416-978-4498
terry.lavender@utoronto.ca
http://www.engineering.utoronto.ca @UofTEng_Media

Leslie Shepherd | EurekAlert!
Further information:
http://www.smh.ca

More articles from Studies and Analyses:

nachricht Innovative genetic tests for children with developmental disorders and epilepsy
11.07.2018 | Christian-Albrechts-Universität zu Kiel

nachricht Oxygen loss in the coastal Baltic Sea is “unprecedentedly severe”
05.07.2018 | European Geosciences Union

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Future electronic components to be printed like newspapers

A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.

The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

A smart safe rechargeable zinc ion battery based on sol-gel transition electrolytes

20.07.2018 | Power and Electrical Engineering

Reversing cause and effect is no trouble for quantum computers

20.07.2018 | Information Technology

Princeton-UPenn research team finds physics treasure hidden in a wallpaper pattern

20.07.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>