Unique AED Pads Give Hearts A Second Chance

An invention by Rice University bioengineering students in collaboration with the Texas Heart Institute (THI) is geared toward giving immediate second chances to arrhythmia victims headed toward cardiac arrest. For their capstone design project, a team of Rice seniors created a unique pad system for automated external defibrillators (AEDs), common devices that can shock a victim's heart back into a proper rhythm in an emergency.

Often, the first shock doesn't reset a heart and the procedure must be repeated, but the sticky pads on the chest must first be repositioned. The pads need to be in the right location to send current through the heart, and someone with no experience who tries to provide aid might miss the first time.

The Second-Chance AED Pads let rescuers try again without losing valuable time to remove the pads from the victim's chest. The pads incorporate three electrodes, two in a single pad with an A/B switch attached, and a third in its own pad.

If one shock doesn't restart the patient's heart, flipping the switch will change the jolt's path, just a little bit, for the second attempt.

The pads were developed by students on the DefibTaskForce -- Lisa Jiang, Joanna Nathan, Justin Lin, Carl Nelson and Brad Otto -- in tandem with Mehdi Razavi, director of electrophysiology clinical research at THI, and their adviser, Renata Ramos, a Rice lecturer in bioengineering.

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."