Ultrathin, electronic medical monitors, resembling tattoos, attach to a patient's skin and can transmit data wirelessly. John A. Rogers / University of Illinois

Confined to hospital beds, patients can only fantasize about stripping off all the wires connecting them to monitors.

Suppose, however, that all of a convalescent patient's electrode patches were consolidated into a single, nearly invisible and weightless version - as thin as a press-on tattoo. And suppose that a tiny radio transmitter eliminated the need for wires.

"Epidermal electronics" - a term coined by researchers who have produced prototype devices at the University of Illinois at Urbana-Champaign - may enable constant medical monitoring anywhere.

The devices are part of a growing field, called mHealth, that uses mobile technologies. Simpler forms include phone apps for patient education or disease management. More complex ones include wireless sensors to monitor vital signs.

"MHealth is managing conditions continuously, so that they don't reach a crisis," says Donald M. Casey, chief executive of the West Wireless Health Institute, a research organization in San Diego, California.

The technology is advancing rapidly. Last year, for example, Corventis, a medical device company based in San Jose, California, received approval from the United States' Food and Drug Administration to market its Nuvant Mobile Cardiac Telemetry System, used to detect arrhythmias. A 5-by-15-centimeter electronic gadget on a patient's chest sends an electrocardiogram to a nearby transmitter, which relays it to a central monitoring center.

"Sensors on everyone, including a 60-year-old watching a football game who doesn't know he's at risk for a heart attack, would greatly reduce the chances of a fatal attack," says Dr. Leslie A. Saxon, a cardiologist at the University of Southern California.

Not all mobile monitoring technology can transmit data wirelessly. The patches that Dr. Saxon uses in one study store their data within; the information is uploaded at the end of the study. In other cases, the technology has been approved only for hospital settings where a doctor is present.

Research on epidermal electronics by the University of Illinois, led by John A. Rogers, an engineering professor, was published last month in the journal Science. While the monitor patch made by Corventis weighs 51 grams, the ultrathin one created at Illinois weighs only 85 milligrams.

Professor Rogers is a co-founder of MC10, an electronics company in Massachusetts that aims to turn the epidermal monitor prototype into a commercial product in 2013. David A. Icke, MC10's chief executive, said the company's skinlike device consists of tiny components that are physically separated, like electronic "islands." They are connected with squiggles he calls "serpentines," which are designed to bend and absorb strain without breaking. The technology can theoretically be used both inside the body and on the skin.

Electronic monitoring of patients at home could significantly reduce medical costs.

In a study by the United States Department of Veterans Affairs published in 2008, researchers tracked patients with serious conditions, including congestive heart failure, from 2003 to 2007. Patients who enrolled in a "home telehealth" program were given biometric devices to monitor their vital signs. These patients showed a 25 percent drop in the number of bed days of care and a 19 percent drop in hospital admissions, compared with the time they were not in the program.

The average cost of $1,600 per patient a year was much lower than the $13,121 spent by the Veterans Department to provide home-based primary care without the "tele" component.

The department also compared the low cost of its telehealth services with the $77,745 per patient a year spent on nursing home care. Yet relatively few patients are being monitored with existing technology.

One obstacle, says Chuck Parker, executive director of Continua Health Alliance, an mHealth industry group, is a lack of financial incentives. He said hospitals have "some fear about the financial implications" for their own operations.

Chantal Worzala, director of health information technology at the American Hospital Association, disagreed, saying, "The vast majority of cardiac patients are over 65 and are covered by Medicare," the United States government health care system for the elderly.

Despite the hurdles, mHealth advocates are optimistic. "If the technology delivers as promised," Mr. Casey says, "then we believe that's when we'll move from sensors on people diagnosed with a disease to literally everybody."

The New York Times

(China Daily 09/18/2011 page10)