Doctors, nurses and other health-care workers at UC Davis Medical Center have been testing candy-bar-sized devices that are part of a new hands-free, voice-activated and wearable communication system.

The Vocera Communications System has been piloted in the main operating rooms on the second floor, and on the North-South Wing of the fourth floor in the main hospital. Selected clinical staff are carrying the devices, called “communicators,” which allow instant, two-way voice conversations without the need to remember a phone number or manipulate a handset.

The communicators, which weigh less than 2 ounces, employ a wireless system that connects the user with others instantly. They are powered by a rechargeable battery with 2 1/2 hours of talk time and 25 hours of standby. An LCD window displays caller IDs and text messages.

“Clinicians spend an enormous amount of time trying to page, call or e-mail each other for very simple but critical communications. This communicator significantly reduces the amount of time folks spend trying to call or page and get a response,” said Lisa Trask, assistant director for Patient Care Services at the medical center.

“For example, it’s absolutely nightmarish when you have both hands on a patient and you need to get in contact with someone immediately, but you can’t step away to make a call,” Trask said.

Silicon Valley-based Vocera Com-munications piloted the tool last year at the Palo Alto Veterans Affairs Hospital, and the pilot program at the medical center began in July and will run through the fall. Medical center officials then will consider using the system throughout the hospital.

The communicator is small and compact because the system’s functions are handled by software that runs on a standard server, connected through wireless access points throughout the center. The access points have to be installed anyway for the implementation of electronic medical records and other wireless computing devices.

A user can say, “Get me Jim and Mary,” and the system also allows for sophisticated organizations and searches. For example, a user may request the communicator to dial the “nearest pharmacist” and the system would call the pharmacist who is closest to the same wireless access point.

Ultimately, Trask said, the system would be able to arrange a multi-party conversation among a patient’s family in Roseville, a nurse at the patient’s bedside in the hospital and a physician in the Ellison Building. Everywhere we are networked,” she said, “we’ll be able to communicate in real time.”