The new lithotripter machine, which removes kidney stones, being installed at Georgetown University Hospital in February will be shared by Arlington and Suburban hospitals in addition to those listed last week.

When a new machine that crushes kidney stones by shock waves received federal approval last year, five Washington area hospitals told health regulators they wanted to buy one of the $2 million devices.

The stampede for lithotripter machines was reminiscent of hospitals' "CAT fever," an earlier quest for computerized axial tomography scanners that provide three-dimensional views of internal organs, and of hospitals' more recent fights to acquire more sophisticated, nuclear magnetic resonance body imagers that cost up to $3 million.

It again pitted hospitals, eager for patients and new technology, against planners trying to prevent the duplication of equipment, with its attendant high cost of underused machines.

Area health planners said that only one kidney stone crusher device was needed in metropolitan Washington, and Blue Cross-Blue Shield said that it would pay claims only from that one machine.

Faced with these circumstances, the medical marketplace tried something new: cooperation. Instead of fighting for the machine, five area hospitals agreed to buy one and share it.

But health planners say that this cooperative effort has been undercut by the Maryland General Assembly, which recently ended that state's regulation of medical equipment purchases.

As a result, two suburban Maryland hospitals -- Southern Maryland Hospital Center in Clinton and Doctor's Hospital in Lanham -- have told state authorities that they each intend to buy lithotripter machines next year.

"It poses a problem for metropolitan planning," said Audrey Murawski, acting executive director of the Southern Maryland Health Systems Agency. "It's a laissez-faire environment now in Maryland. Consumers no longer have a voice over whether medical equipment is needed."

She said that councils and citizens groups are appealing to Maryland legislators to reinstate controls on medical equipment.

In agreeing to share one lithotripter, Georgetown University, Sibley Memorial and Howard University hospitals in the District, Suburban Hospital in Bethesda and Arlington Hospital in Northern Virginia agreed to place the machine at Georgetown and refer their patients there.

Georgetown, in turn, agreed to allow outside doctors to perform the procedure, once they receive the necessary training.

Local health planners have denied applications for the machine from George Washington University Medical Center, the Washington Hospital Center and Fairfax Hospital, although Fairfax has appealed the decision of the Virginia Health Department to the Fairfax County Circuit Court.

Pam Barclay, director of the Washington Area Council of Health Planning Agencies, said that the lack of equipment regulation in Maryland will cause a "proliferation" of costly medical machines.

"We won't know just how many more lithotripters we'll have, until the court case in Fairfax is settled," she said.

Defending Southern Maryland Hospital Center's decision to buy its own machine, spokeswoman Peg Greenway said that the hospital has a special interest in the kidney stone crusher because the hospital's owner, Dr. Francis Chiaramonte, is a kidney specialist.

Barclay said the situation in Maryland also poses problems for the Washington area where other medical technology is concerned.

"There is tremendous interest in starting cardiac catheterization labs in Maryland, in and outside of hospitals," she said. "We're facing an uphill battle trying to limit technology to what's needed."

Demand for the lithotripter is great because patients avoid surgery, with its complications and eight- to 10-day hospital stays; an average lithotripter treatment takes one hour. The cost of a treatment is about $5,000, or half of that usually charged for surgery, and patients need only about a two-day recovery period.

The device, which crushes stones by focusing shock waves on them, can perform 1,400 treatments each year. The Metropolitan Washington Area Council of Health Planning Agencies estimated that only 800 kidney stone patients in this area will need the treatments each year.

Dr. David Seitzman, who formed the Urologic Stone Center of Metropolitan Washington with 10 other local urologists, said he agrees with health planners' estimates that only one machine is needed locally.

"There could be a potential problem," he said. "When you get machines and people aren't using them, there's a tendency to shift costs to other items. We're all worried about overreplication."