Today's sophisticated medical equipment is getting tripped up by its power supply.
Medical equipment's vulnerability to sags, swells and other electrical disturbances is one reason behind the high cost of its maintainance, experts say.
So-called "dirty" power damages the delicate microprocessors that help run everything from alarm systems to patient monitors to computerized tomography scanners, they said. Electrical noise, caused by poor wiring or other equipment, also can wreak havoc.
Sometimes a flicker in the power supply can turn radiology images grainy or drive blood-gas analyzers out of whack, said Grant Gehlbach, a biomedical engineer at 276-bed AMI Piedmont Medical Center in Rockhill, S.C.
The cost and prevalence of power-quality problems is difficult to quantify, experts said. Hospitals don't always identify dirty power and electrical noise as the sources of equipment trouble. Also, power quality at hospitals and equipment's sensitivity to it varies widely.
One hospital cut spending to maintain radiology equipment by $243,506-almost 50%-after it cleaned up the power supply in an 11-year-old building.
In 1992, a host of troubles plagued an X-ray system at 493-bed St. Joseph's Hospital and Medical Center in Phoenix, Ariz. When electrical components burned up mysteriously, engineers installed a filter to condition the power. When symptoms of poor power quality showed up elsewhere, they looked over wiring and grounding throughout the facility. The hospital's efforts cost $75,875, but net savings totaled $167,631.
"I would say about 80% of our maintenance were power problems," said Mike Garnica, a biomedical engineer for the radiology department. "We were always on the run. It was like a forest fire we couldn't put out."
Outdated hospital buildings and inadequate infrastructure at utilities often cause power problems. Poor design of some medical equipment contributes, Piedmont's Mr. Gehlbach said. Meanwhile, manufacturers don't always reveal exactly how sensitive their equipment is to power variations.
"There's enough blame to go around," he said. "What we have done with electronics is so spectacular, it has outstripped the distribution system."
Products to guard equipment abound, from simple surge protectors to $100,000-plus uninterruptible power supply units. A profession, devoted to cleaning up power at hospitals and other businesses, is emerging.
One example is 18-month-old Power Quality Engineering. So far, several businesses and eight hospitals, including St. Joseph's, have hired the Phoenix, Ariz.-based company to look at trouble spots. The company often urges a total audit of the facility's power-distribution system.
"There is no one cure, no panacea" to power-quality problems, said Michael Pearson, its president. "It takes an engineering solution."