The sister of Dr. Herman Tarnower finally had to leave the courtroom. Jean Harris could not listen, and tried to avoid the testimony by averting her head and then putting her hands over her face.

The pain came from the testimony today of the surgeon who tried desperately to save Dr. Tarnower after he had been shot in his bedroom last March. He spoke in Harris' murder trial here about the doctor's last hour, and it was strong stuff, grimly clinical.

"We placed him on the examing table when he arrived. He had no respiration, no heartbeat, no blood pressure," the surgeon, Dr. Vito Marrero, began, testifying for the prosecution.

"We passed a tube down him and started breathing for him, and gave him external cardiomassage, anything to try to get some semblance of vital signs . . . . We passed a small catheter into his lung, and there were copious amount of dark blood spilled out . . . . We inserted a chest tube into his lung and it returned a big gush of blood . . . . an estimated total of 1,500 ccs [cubic centimerters], I would say . . . . "

Harris clutched at the arms of her chair, her face pale. Tarnower's sister, Pearl Schwartz, long since had fled.

"And how long would you say you worked on the doctor?" asked the assistant district attorney, George Bolen.

"Twenty minutes," was the reply.

"And did you know, of your own personal knowledge, was he alive or not when he arrived at the hospital?" the prosecutor asked.

"I don't think I could say," said the surgeon. "You try to salvage them despite the evidence of being without vital signs. You assume that only recently the vital signs stopped, maybe a second or so, but after a time, when there are no signs of life, after no hert activity, your patience runs out."

Harris, 57, the former headmistress of the Madeira School in McLean, is on trial for second degree murder. She is accused of shooting her lover, Tarnower, in the bedroom of his home last March.

The prosecution in the case, noting that Tarnower had been dating another, younger woman, has insisted that Harris shot him in a jealous rage. The defense -- led by the pugnacious and theatrical Joel Aurnou -- has maintained that the shooting was "a tragic accident," a suicide attempt that went wrong. Harris, the defense insists, went to the doctor's home to kill herslef and, in the struggle that somehow ensued when she told the doctor of her intentions, the gun went off.

One of the problems with this argument is that the gun went off more than once -- though just how many wounds the doctor suffered is a matter of contention. The prosecution, claiming Harris acted "consciously, volitionally, voluntarily, and intentionally" also said in the opening arguments of the trial that she fired five shots at the doctor. Four hit the mark, Bolen said, including one in the back.

Defense attorney Aurnou, in his opening statement, disagreed, promising some surprises as the trial unfolded.

"Mr. Bolen told you that the doctor had been hit four times in the body, but that's not quite the way it happened," he said. He also added that, in the case of the injuries to the doctor's hand, "the gun was not aimed at the doctor when the gun went off."

Today's testimony by surgeon Marrero was the first testimony to deal with the question of the wounds -- although expert ballistics testimony, on both sides, is expected later.

Under direct examination by assistant district attorney Bolen, Marrero said that there were indeed four wounds, and described them in detail.

"The right hand appeared to be pierced, the right upper arm was completely broken and bent back in a 90-degree angle, with a wound over the break, there were two wounds on the chest, an anterior wound . . . posterior wound," Marrero intoned.

But in his cross-examination, Aurnou seemed to be trying to establish that Tarnower had not been shot in the back, that the injury to his back had been merely an exit wound.

"You mentioned a wound in the front near the clavicle and a wound in the back. Did those appear at the time to be a through-and-through wound to you?" asked Aurnou.

An objection from the prosecution prevented an answer.

"Did you make any attempt to see whether the wound from the chest area and from the back of the shoulder were the same bullet?" Aurnou tried again.

"No, I did not," said the surgeon.