RICHMOND, FEB. 5 -- After an emotional personal appeal from freshman Del. Phoebe M. Orebaugh (R-Harrisonburg), the House of Delegates voted today to make Virginia the second state in the country to seek the use of heroin for cancer patients with intractable pain.

Federal legislation, pending in Congress, must be approved before the state could implement such a program. Proponents said passage of the bill in a traditionally conservative state like Virginia could encourage passage of the federal measure.

Orebaugh recalled for her fellow delegates the pain her brother-in-law endured the night he died, despite the large amounts of morphine he was given:

"For the entire night, he screamed so loud he could be heard all over the hospice. He begged my sister to smother him with a pillow . . . . He told her, 'I'm dying like an animal.' "

Members of the House Health, Welfare and Institutions Committee split 9 to 8 on the issue when it approved the bill earlier this week. Today's passage by the full House was by voice vote, with a strong dissent. Final House passage, normally routine, is scheduled for Monday.

Opponents of the measure have argued that the heroin could be diverted and result in more street use of the highly addictive drug. While some doctors have spoken in support of the bill, the Virginia Medical Society has called it "premature" and did not endorse it.

"I'm not sure the legal distribution of heroin is where we want to be on the cutting edge," Del. Robert W. Ackerman (D-Fredericksburg) commented in opposing the bill on the House floor.

Under the bill, doctors would be registered to dispense heroin to terminally ill cancer patients, and regulations would be drawn up on recordkeeping, storage and identification of patients eligible to receive the drug. Having set the operating procedures in place, said lawmakers, would save time in starting the program in Virginia upon passage of federal legislation.

Supporters have said the heroin that would be distributed legally under the program equals no more than 4 percent of the amount available on the street. They also argue that heroin use for intractable pain is allowed in other countries, including Great Britain.

"I think I'm going to have a problem in the Senate," Orebaugh acknowledged after the House vote. While there is support there for it, no one in the Senate is pushing the measure as strongly there as she did in the House, Orebaugh said.

Congress at one time was expected to approve easily a bill to allow heroin use for cancer patients in intractable pain. In the fall of 1984, however, the House of Representatives defeated it overwhelmingly in a vote that some observers attributed to the approaching election and the potential for the bill's being interpreted as a liberalization of drug laws.

"This is the bill we need to get Congress moving," said Del. Alan E. Mayer (D-Fairfax). Mayer had voted in committee against the bill, saying it was not in the right form for its intended purpose, but he announced he was voting for it on the House floor.