St. Vincent Catholic Medical Centers, the city’s largest Catholic hospital network, filed for bankruptcy protection yesterday, after several years of speculation about how the financially struggling system would get out of the red.

The seven-hospital system, which includes one hospital in Westchester, has arguably had the rockiest run of any health-care system in the city. Even before the Chapter 11 filing, it had eliminated major services at one of its hospitals on Staten Island and announced plans to shut one in Brooklyn.

Hospital officials, who announced the bankruptcy decision on their Web site and filed paperwork in federal Bankruptcy Court in Manhattan, said the move would not affect surgical and medical services. Its last-ditch attempt to pull itself from its financial hole did, however, have doctors and other health-care professionals wondering about the institution’s future.

“This really gives us the chance to take a timeout,” a hospital spokeswoman, Bernadette Kingham-Bez, said. “This is not a liquidation. We intend to be delivering health care to New Yorkers for many years to come.”

Health-care professionals said the move could hinder St. Vincent’s ability to borrow money and to deal with vendors, who provide everything from gauze pads to bedpans.

Ms. Kingham-Bez said, however, that the court approved a $15 million loan from HFG Healthcare IV, a finance company, yesterday so that the institution could pay its 11,500 employees and meet other immediate financial obligations.

St. Vincent’s flagship hospital, on West 12th Street, became the primary triage facility after the World Trade Center attacks in 2001. Mayor Giuliani became a prominent supporter of the hospital, holding fund-raising events in his home, and St. Vincent’s named its trauma center for him.

Speculation about a possible bankruptcy filing by St. Vincent has been swirling since the city’s Catholic hospitals merged in 2000, but conversations among top-level managers intensified late last week when the St. Vincent board held a five-hour meeting to discuss financial options. The board’s final decision was voted on during an emergency meeting on July 4, to which members were patched in through a conference phone call.

A turnaround, after already-painful belt tightening, will not be easy. The hospital system has $1.1 billion in outstanding debt, it serves a high-percentage of uninsured patients, and it ended 2004 with an operating loss of $153 million. Aggravating matters, the system had been trying to fix its problems based on an inaccurate balance sheet. A previous audit had overstated revenue by $60 million.

A senior manager at Standard & Poor’s, Martin Arrick, called the filing a “major blow to Catholic health care.” Mr. Arrick said that he had not reviewed the St. Vincent situation, but that when hospitals file under Chapter 11, they often face an “immediate liquidity crisis” because suppliers want “cash on demand.”

The president of the United Hospital Fund, James Tallon, said the move “lends an air of uncertainty” to the medical centers’ financial situation. He said, however, that he expected officials at St. Vincent would “find a way to work their way out of it over time.”

In April 2004, the system hired a Boston-based firm, Speltz and Weis, that specializes in turning around struggling hospitals. David Speltz was installed as the institution’s president and CEO and is still serving in that capacity.

In a letter posted on the institution’s Web site yesterday, Mr. Speltz said the decision was “difficult but necessary” because of cash flow problems.

His firm takes credit for steering Crouse Hospital in Syracuse out of Chapter 11 and turning a $20 million deficit into a $700,000 profit. Whether the same will be feasible in New York City is unclear.

Meanwhile, a small community hospital in Queens, Parkway, filed for Chapter 11 bankruptcy protection Friday. That hospital, which had also been struggling, is not nearly the size of St. Vincent’s, but its difficulties further highlight the impact on health care in New York and elsewhere of shrinking reimbursements and rising costs.

Despite its closure of Bayley Seton Hospital on Staten Island, where services were gradually eliminated until the hospital was on life support, and the recent announcement that the system was seeking state approval to shut St. Mary’s in Brooklyn, St. Vincent had, until yesterday, denied it was on the brink of a bankruptcy filing.

The Reverend Alford Sharpton, who in the 1980s had an office at St. Mary’s – which serves some of the most blighted communities in the city – said the only way St. Vincent would succeed in closing the Brooklyn facility would be “if they drag some of us out in handcuffs.”

“I’m prepared to move into that hospital with others and engage in civil disobedience to stop it from closing,” he told The New York Sun yesterday.

A spokesman for the state Department of Health, Robert Kenny, said officials there would work with St. Vincent. It was unclear yesterday whether St. Vincent was trying to secure a state bailout.

Last month, Governor Pataki created an 18-member Commission on Health Care Facilities in the 21st Century. Mr. Kenny said yesterday: “Hospitals facing the challenges of restructuring need to take whatever steps make the most sense to help them reinvigorate their operations.”

“There is not one answer that fits all,” but most hospitals emerge from bankruptcy as “strong providers,” he said.

The Service Employees International Union/Local 1199 issued a statement that said it was “deeply troubled” and would “work aggressively” to make sure St. Vincent made good on its payments to employees.

Though St. Vincent has publicly acknowledged its problems, many doctors and employees were taken aback by yesterday’s development.

An obstetrician who delivers babies at St. Vincent’s on Staten Island, Dr. Radha Syed, said she expected more cuts despite the hospital’s assurances.

“If they are declaring Chapter 11, there are going to be services that are stopped,” she said.

The Catholic hospital system’s bankruptcy filing came only months after financial difficulties led the city’s two Catholic archdioceses to announce the closings of dozens of parochial schools in the five boroughs.