Jane Frances Bolding, a former Prince George's Hospital Center nurse charged with killing three patients under her care, said in five emotional hours of testimony yesterday that she told police she injected a patient with a fatal dose of potassium and wrote an apology to the woman's family only to end 22 hours of continuous questioning from homicide detectives.

Bolding, testifying before Circuit Judge Joseph S. Casula, said that from about 1 p.m. on March 19, 1985, until about 11:15 a.m. the next day, she maintained her innocence against accusations from county detectives that she had injected massive doses of potassium into intensive care patients to end their suffering.

By 11:20 a.m., Bolding testified, Detective Mike McQuillan began writing documents charging her, saying police had evidence to show Bolding had injected lethal doses of potassium into as many as 17 patients.

"He said, 'Just tell me one name, and we can tear up the papers,' " Bolding testified. "I gave him Mrs. {Elinor} Dickerson's name. I had to make him quit writing.

"I was tired. My stomach was upset. I would fall asleep, and he would wake me up. He told me as soon as I was done writing the letter, he would bring me a cot in, and I could get some sleep. He said he was going to use the letter to help me."

Bolding faces three charges of first-degree murder and seven counts of assault with intent to murder for allegedly administering massive doses of potassium to five patients between March 1984 and March 1985. If convicted, Bolding could be sentenced to as much as life in prison for each count of murder and 30 years for the lesser assault with intent to murder charges.

Bolding, 29, began working at the hospital in 1980 and resigned in March 1985.

Bolding's first public statements about her lengthy interrogation and arrest on a first-degree murder charge in the death of 70-year-old Dickerson came in the fifth day of a Circuit Court hearing to determine whether Bolding's statement to police, in which she allegedly said that she injected a massive dose of potassium into Dickerson, will be allowed as evidence in Bolding's trial.

Fred Joseph, Bolding's attorney, has asked Casula to suppress Bolding's statement because, he argued, it was given under duress after almost 24 hours of questioning. Joseph also said that police denied Bolding's repeated requests to speak with a lawyer during the questioning.

Assistant State's Attorney Jay Creech, who is prosecuting the case, said that police treated Bolding kindly during the interview, giving her Diet Coke, coffee, cigarettes and food whenever she wanted it. Police who testified this week said Bolding never asked to speak with a lawyer.

Her indictment last December capped an 18-month investigation by county homicide investigators, who were asked by hospital administrators in March 1985 to look into a series of suspicious heart attacks at the hospital's intensive care unit.

Bolding originally was charged with one count of first-degree murder, that of Dickerson.

But that charge was dismissed in May 1985 by then-State's Attorney Arthur A. (Bud) Marshall Jr., who cited a lack of evidence. Marshall also said Bolding's statement to police might not be admissible because it followed almost 24 hours of police questioning.

Bolding was indicted after prosecutors received a statistical report on the mortality rate at the hospital's intensive care unit prepared by the federal Centers for Disease Control, which Marshall said strengthened the case against Bolding.

The CDC report said that a disproportionate number of Bolding's patients suffered cardiac arrest while in her care. Bolding was the attending nurse in 57 cases -- or 40 percent -- of the 144 fatal and nonfatal cardiac arrests recorded in the hospital's intensive care unit between January 1984 and March 1985, according to the report.

Bolding testified that she repeatedly asked detectives to let her talk with a lawyer, and they told her that twice lawyers came and left messages for her. Bolding testified that McQuillan gave her a note from Steve Lemmey, one of Bolding's lawyers, after she had written two letters of apology to Dickerson's next of kin -- more than 24 hours after police had brought her to the Criminal Investigations Division in Forestville.

"{McQuillan} told me to be careful," Bolding testified, "because lawyers were there only to get money and that police had my best interests at heart."

On Thursday, three lawyers testified that they had gone to the police station to talk to Bolding but were denied access to her by detectives, who said Bolding did not want to talk with them.

Marilyn Ermer, a lawyer for the Maryland Nurses Association, testified that she waited at the police station from 2:40 to 8 p.m. on March 19, 1985, without seeing Bolding. Ermer said one detective told her that the only way she would see Bolding was "to get arrested."

Another lawyer, John Mowery, obtained a court order to get Bolding released. But the issue was moot because by then -- between 3:30 and 4:30 a.m. on March 20, about 28 hours after the questioning began -- police had charged Bolding with first-degree murder.

Bolding is charged with killing Dickerson on Sept. 28, 1984; Isadore Schreiber on Oct. 12, 1984, and Martha Moore on Oct. 28, 1984.