Dr. Wendy Fried said a patient was so grateful for saving her and her baby's life during childbirth that she invited the doctor to Christmas dinner.

When the woman turned around and sued her months later, "it was like a knife in my heart," said Fried, an obstetrician-gynecologist who practices in North Hills.

The case went to trial and after three days deliberation the jury found Fried not guilty. That was about 10 years ago but the memory is still painful.

"This was one of the most emotionally devastating situations, not only in my career but in my life," said Fried, who said she has been named and dropped in two other lawsuits during 18 years of practice. "It was the ultimate in betrayal."

The experience left her a believer in the need to change the way medical malpractice cases are handled. The system, she said, can lead to doctors altering the way they practice to protect themselves legally - "defensive medicine," it's called - and to costly malpractice insurance premiums.

Because of malpractice lawsuit payouts, Nassau and Suffolk have the highest malpractice fees in the state and the sixth-highest in the country, according to the newsletter Medical Liability Monitor. Fried pays a "discounted" rate of $170,000 a year in insurance but other ob-gyns in Nassau and Suffolk pay $177,830 or $194,935, depending on their insurer.

Long Islanders appear to agree the system should be changed. In a recent Newsday poll of 1,037 registered voters, 75 percent were somewhat or completely in favor of limits to malpractice lawsuits.

But Michael Duffy, a malpractice lawyer in Uniondale, said the system is the main way to protect the patient. "The entire conversation has focused on whether money can be saved and physicians can be made to feel more comfortable," Duffy said. "But what is not being talked about is . . . the tens of thousands of deaths and certainly many more injuries made by avoidable [medical] errors."

The debate over what is known as "tort reform" sets two main forces in opposition: doctors and malpractice insurers, supported by many Republicans, who maintain that it could save billions in health care; against trial lawyers, some consumer groups and many Democrats who say it would have little impact and could reduce patients' rights to justice.

On Oct. 9, the nonpartisan Congressional Budget Office calculated that an array of changes in the tort system could save about 0.5 percent, or $11 billion in 2009, in national health care spending. Over the next 10 years, the changes could reduce the federal deficit by $54 billion, the office said. But this year alone, that deficit is projected at $1.75 trillion.

This is the first time the agency has put a cost on defensive medicine, when doctors feel compelled to order extra tests, hoping to ensure they aren't sued later. The agency calculated about 60 percent of the savings - or $32.4 billion - would be from the "slightly less" use of health services.

But Joanne Doroshow, executive director of the Center for Justice & Democracy, a consumer group in Manhattan, said the agency's findings didn't match "the rhetoric" from tort-reform advocates and would have little impact on reducing the more than $2 trillion spent each year on health care.

In his address to Congress last month, President Barack Obama reached out to doctors and Republicans when he said the administration would find money for projects to look at alternatives - such as special medical courts - to make sure patients are fairly compensated but also to reduce frivolous lawsuits.

Looking at alternatives to lower costs makes sense, said Ed Amsler, vice president of Medical Liability Mutual Insurance Company, the state's largest medical malpractice insurer. In close to 70 percent of its malpractice lawsuits, the company paid nothing to the plaintiff last year, he said, either because the cases were dropped or a jury found in the doctor's favor. Yet each case cost the company $30,000 to $40,000 in attorneys' fees, he said.

In the other 30 percent of cases, the company's average payout was $511,000 last year, up from $456,000 in 2004. This increase drives doctors' premiums higher, he said - though in New York the legislature has held premiums steady since they rose 14 percent in 2007.

Yet a recent report by Americans for Insurance Reform, a coalition of patient rights groups, found no correlation between states that had instituted some malpractice liability limits and how much money doctors paid in premiums. Instead, the report found spikes in premiums were related to the economic cycle of insurers and drops in investment income.

But Fried, like many doctors, said she believed the need for change was urgent, because doctors will begin leaving their practices. A recent study from the Center for Workforce Studies at the University of Albany found that, although there is no shortage now of doctors except in rural areas, the demand for physicians could exceed supply in the next several decades.

"You are just not going to get people who are willing to practice anymore," she said. "You're not going to get the best and brightest."