The corporation that runs Prince George's County's three public hospitals reported yesterday a $10 million operating loss for the fiscal year that ended in June, about $7 million higher than previous estimates.

Winfield M. Kelly Jr., the former county executive who is chairman of the Community Hospital and Health Care Systems Inc. (CHHCS), said that rising expenses and declining patient volume were two of the "significant problems" that contributed to the deficit. The hospitals, according to the same statement, lost $1.1 million last year.

Arnold Katz, the district comptroller for the Hospital Corp. of America (HCA), a management firm hired in August to turn around the troubled facilities, had previously said that the deficit would total $3.5 million.

The operating loss is another in a series of obstacles the hospital corporation has faced in recent months, including the resignation of its board and the layoff of 615 employes. Hospital officials said yesterday the new financial information probably will not mean any further job losses and will be offset with streamlined management procedures that have already been implemented.

"No matter what figures you're using," Kelly said yesterday, the loss "is bigger than I thought it was."

Corbett A. Price, HCA's district vice president, said he believed all along that losses would be more substantial than the projections that were based on CHHCS record keeping.

"It is just again an example of poor management" by CHHCS, Price said yesterday.

The three county-owned facilities are the Prince George's General Hospital, Greater Laurel-Beltsville Hospital and the Bowie Health Center.

Richard Wade, a spokesman for the Maryland Hospital Association, said yesterday that it is "not an accurate statement" to blame previous management for all of the corporation's fiscal problems.

Empty hospital beds and increasing costs are "a national problem," he said. "Thirty-five percent of the nation's hospital beds are empty today."

The August layoffs, Wade added, were similar to cuts that other hospitals in the state have been making over the last few years.

Price said he does not anticipate any reductions in service as a result of the newly documented loss. "I think that the hospital system has in fact selected the most appropriate course to bring about a change," he said, adding that it "will take us some time to have a complete turnaround."

Kelly predicted that the corporation should break even by early next year, partly as a result of the August layoffs.

A labor arbitrator ruled last week that the corporation was justified in terminating the employes but that it was inconsistent in the way it applied seniority rules among nurses.

Arbitrator Herbert Fishgold said in a 76-page decision that there were "violations, misapplication and inequitable application" of a seniority protection clause in the nurses' union contract.

Carol Bragg, president of the Prince George's Staff Nurse Association, said that about 40 nurses will be affected by the ruling even though it does not necessarily guarantee that they will get their jobs back.

"It is the greatest test of our contract in the 11-year history of our association," she said.