Rice University bioengineering students have developed a modified set of external defibrillator pads that can provide an additional option for cardioverting the heart. 
Three electrodes are embedded between two pads and a switch selects which path for the current to take. By following simple user instructions, bystanders can easily provide a second option that’s not available in current defibrillators. The system, which was created to transparently improve the efforts of untrained public responders, can be adapted to existing defibs.
The potential for their project was clear from the beginning. “We did some calculations that suggested we could save at least 13,000 lives per year,” Otto said. “Cardiac defibrillation is very time-sensitive. Thirty seconds can be the difference between life and death in a lot of situations. The time it takes to flip the switch is negligible compared with the time it takes to remove the pads, shave and prep a new area on the body, reapply the pads and administer another shock. And a layman might not even know to try a second position.”
Rather than try to build a new type of AED, the team decided early on that it was enough to simply design new pads that would fit devices that are already in use. Manufacturers generally require AED pads be replaced every two years, which provides a ready market for the students’ invention. “But well over 100,000 AED units are produced every year, so even if our pads are only paired with new AEDs, we have a significant market,” Lin said.
Getting the instructions right turned out to be just as important as the device itself and required a lot of illustrative trial and error. In tests for the final version at Rice’s Oshman Engineering Design Kitchen, the team recruited students with no experience using an AED to shock a medical mannequin back to life. “We had 100 percent of the testers place the pads correctly, showing it was very intuitive to use,” Jiang said.
Full story: Unique AED pads give hearts a second chance…
