Deep feelings of mistrust between doctors and lawyers, two of the nation's most prominent professional groups, erupted today at a hearing on proposals to curtail the skyrocketing costs of medical malpractice insurance.

Calling such changes crucial to solving the problem of increasingly scarce and expensive liability insurance, a dozen doctors and insurance company representatives appeared before the Senate Judiciary Proceedings Committee to urge adoption of the proposals. The 28 bills are designed to make malpractice and other civil lawsuits more difficult to bring and make successful lawsuits less expensive.

In turn, as many lawyers turned out in force to oppose the bills, calling them largely symbolic measures that would have no effect on the insurance drought while unfairly limiting individual rights. Altogether about 200 people jammed the committee room.

"There is not the slightest evidence that any of these so-called reforms will reduce the insurance premiums of doctors in the slightest," said George Shadoan, a trial lawyer and member of one of two gubernatorial task forces that reviewed the problem of liability insurance.

The bills would affect the liabilities of professionals other than doctors. And some of the most emotional testimony today came from persons who, while not victims of medical malpractice, had suffered horrible disfigurement and successfully sued for compensation.

"I'm still in pain," Valerie Lee Fraling said, as a result of the third-degree burns she suffered over 60 percent of her body from an explosion that occurred as she pumped gas into her car in the summer of 1976.

Her lawyer, Jerome Seidenman, successfully sued both the gas station and the pump manufacturer for "substantially more than $250,000," he said. He and Fraling testified against a bill that would cap "pain and suffering awards" for noneconomic damages at $250,000 and require that jury awards be paid out in increments instead of in a lump sum.

Fraling, whose face and hands bore the scars of the searing heat that had melted her skin as well as the numerous operations to repair them, said she wanted to testify because "it would be sad to think that someone else could go through this and not be adequately compensated -- not that monetary compensation will ever make the pain go away."

Dr. Barry Wolk, a Baltimore obstetrician whose insurance premiums for a three-doctor practice have nearly tripled from $39,500 to $108,000 in the last year, called such testimony "showboating" by the lawyers and said, "who put the lady's face back together? . . . It was a highly skilled physician. You always hear about the one bad case, but we never get the credit."

Wolk, along with other physicians and insurers, supported measures that would:

*Make medical malpractice cases harder to bring by requiring plaintiffs to produce, before filing a suit, evidence by a physician that malpractice may have occurred.

*Cap jury awards for noneconomic losses in all civil suits at $250,000, require that jury awards be paid in increments, and allow evidence to be introduced that a victim had already received some benefits as a result of the injury.

*Limit legal fees.

*Restrict the time in which persons can file some lawsuits.