CHICAGO – Wireless systems used by many hospitals to keep track of medical equipment can cause potentially deadly breakdowns in lifesaving devices such as breathing and dialysis machines, researchers reported Tuesday in a study that warned hospitals to conduct safety tests.

Some of the microchip-based “smart” systems are touted as improving patient safety, but a Dutch study of equipment – without the patients – suggests the systems could actually cause harm.

A U.S. patient-safety expert said the study “is of urgent significance” and said hospitals should immediately address the “disturbing” results. A Bangor hospital uses the technology to track nurses, but a spokesman said no problems have been associated with the system.

The wireless systems send out radio waves that can interfere with equipment such as respirators, external pacemakers and kidney dialysis machines, according to the study.

Researchers discovered the problem in 123 tests they performed in an intensive-care unit at an Amsterdam hospital. Patients were not using the equipment at the time.

Electromagnetic glitches occurred in almost 30 percent of the tests when microchip devices similar to those in many types of wireless medical equipment were placed within about one foot of the lifesaving machines.

The wireless systems are used to tag and keep track of medical equipment such as heart-testing machines, joint replacements and surgical staplers. They can help quickly locate devices that are elsewhere in the hospital and help prevent theft.

The results show that it’s crucial for hospitals to test their wireless items before using them around equipment essential for keeping patients alive, said Dr. Erik Jan van Lieshout, a study co-author and critical care specialist at the University of Amsterdam’s Academic Medical Center.

His study appears in today’s Journal of the American Medical Association.

Peper Long, a spokeswoman for the Food and Drug Administration, said the agency is aware of the potential problem but has not received any reports of injuries directly caused by electronic interference with hospital medical devices.

At Eastern Maine Medical Center in Bangor, Dr. Ehab Hanna, the assistant chief medical information officer, said Tuesday that the hospital uses tracking technology only to monitor the whereabouts of nurses. Tracking chips are embedded in the nurses’ name badges, he said, allowing the nurses to be located quickly in an emergency. The technology is not used in the intensive care unit where there is “sensitive equipment,” he said. Hanna said there had never been any equipment malfunction or other mishaps linked to the system, which has been in use for at least six years.

EMMC has been cautious about adopting tracking technology for equipment and supplies, in anticipation of more clinical evidence of its value and safety, Hanna said.

BDN staff writer Meg Haskell contributed to this report.