When undergoing medical treatment, physicians frequently determine that a patient's vital signs — such as blood pressure and heart rate — need to be closely monitored. For most patients today, this means a variety of wires and sensors will be attached to their bodies. But thanks to technology developed at NASA, there might be a better way.

A new biomedical sensor that incorporates technology pioneered at NASA's Glenn Research Center in Cleveland, Ohio, is currently being developed by a company called Endotronix. The company is investigating using the sensors to measure blood pressure and heart rate.

“When this opportunity came about, we immediately understood that we could tailor our technology for a biomedical application. It was an opportunity for direct societal impact that could assist a lot of people in the medical community," says Dr. Félix Miranda, one of the two Glenn scientists responsible for the technology.

The sensors are about the size of the head of a pin — 1 mm wide and 0.5 mm thick. Crafted out of gold and silicone, each tiny sensor also includes a multi-turn loop antenna, which means data collected from the sensor can be wirelessly transmitted to an external unit. Called Biomedical Microelectromechanical Systems, or Bio-MEMS, each sensor makes use of NASA-patented radio-frequency technology.

Dr. Félix Miranda, a supervisory electronics engineer, and Dr. Rainee Simons, a supervisory physicist, are both part of the Communications, Instrumentation, and Controls Division at Glenn. In 2001, the Technology Transfer and Partnership Office (TTPO) at Glenn awarded the team $50,000 to work toward finding a way to use Glenn's radio-frequency technology in the biomedical field.

Initially, the two were investigating the technology for potential use in space suits, as a way to remotely monitor astronauts' health. The initiative was especially important for astronauts performing space walks, and could prove essential as plans develop to send astronauts further into space.

“There is an emphasis to develop sensors for astronauts that are convenient as well as accurate. Safety is the initial motivation,” Simons says.

Drs. Miranda and Simons achieved patents for their work in 2003 and 2007, and extensively published their work. Through these publications, Dr. Anthony Nunez, a cardiovascular surgeon and president of Endotronix, learned about the work at Glenn in 2006.

Endotronix now holds the exclusive license for cardiovascular applications of the Glenn technology. Glenn and Endotronix signed a Space Act Agreement to work on developing and validating the technology for these particular medical uses. Though the Space Act Agreement has now ended, Endotronix keeps Drs. Miranda and Simons updated on its progress.

How it Works

The cardiovascular sensors will operate by being implanted in the body of the patient. Each tiny unit doesn't require a battery, which means that it can last indefinitely in the body while causing less damage to surrounding tissue and lessening the risk of infection or toxicity. The device, manufactured out of biocompatible materials, operates by sensing the pressure that the heart or an artery creates when the blood flows by a membrane. It transmits data to a small, portable external reader, which can be worn by the patient or kept nearby for readings. This transmission occurs wirelessly, and the absence of a wire in the body also helps prevent risk of infection and other negative side effects.

Because the sensors are so small, they are not disruptive to the patients in whom they are implanted. All types of patients can potentially benefit from the device, from nursing home residents requiring intensive care to active patients who wish to travel, while still monitoring their health. The external readers are easy to use, allowing patients to take their own readings.

“As this technology evolves to be a product for the general public, it needs to be as simple as possible without sacrificing the accuracy of the information,” Miranda says.

Where it Stands

Endotronix has licensed the technology for cardiovascular applications, but there are other potential uses for these pressure sensors. Companies have expressed interest in investigating the technology for other biomedical areas, such as general surgery and bone, neck, and spine health. Other areas of human interest, like structural safety in bridges and buildings, could also benefit from this technology.

The technology, used for both aerospace and non-aerospace applications, is notable. It is the second largest licensing of intellectual property at Glenn and has pioneered a new area of collaboration with the commercial sector.

“This is the very first medical and surgical application for space biosensor technology,” Simons says.

Drs. Miranda and Simons are pleased with how their research has been integrated into the medical field, and they are looking forward to seeing what new areas — biomedical and beyond — the sensors may influence.

More Information

For more information on Endotronix’s biomedical sensor, visit http://info.hotims.com/28057-148.

Medical Design Briefs Magazine

This article first appeared in the September, 2010 issue of Medical Design Briefs Magazine.

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