While driving down Sunset Boulevard late at night last month, actor Howie Mandel -- who plays Dr. Wayne Fiscus on NBC's weekly medical drama "St. Elsewhere" -- spotted an accident. A car had careened off the road, and the driver was still in her seat, blood gushing from her forehead.

Mandel pulled over, heart pounding and mind abuzz with medical facts picked up in four seasons as the eagerest beaver in "St. Elsewhere's" frenetic emergency room.

"I stopped to see if there was anything I could do," he recalled. "What's weird is, I think I know more than I do."

The injured woman wanted to climb out of her car. Pushing past other onlookers, Mandel ordered her to stay where she was until an ambulance arrived.

The others looked at him in amazement, he said. One of them gasped, "Dr. Fiscus ?"

Life may occasionally imitate "St. Elsewhere," but "St. Elsewhere" regularly imitates life. At least, that seems to be the consensus among many medical professionals who tune in every Wednesday night to join Fiscus and his coworkers at St. Eligius, a gritty public hospital fictionally located in Boston.

"I don't know how they manage to do it where other shows don't, but it's really got so much of the tragicomedy of life in a hospital," said psychiatrist Michael I. Bennett, who trained at Boston's Beth Israel Hospital.

"Some things that happen in a hospital are bizarre, and people on the outside really wouldn't believe it," said Dr. Gary Malakoff, chief medical resident at George Washington University Medical Center. "From our point of view, 'St. Elsewhere' sort of legitimizes what goes on."

The same realism that attracts doctors, however, can make the show difficult for some patients to watch. Betsy Zachary of Los Angeles, a former fan, has been unable to watch St. Elsewhere since she underwent lung surgery a year ago. Her hospital experience "was just amazingly similar. It was the pitch, the fever pitch . . . It's recreating something I really choose to forget," she said.

"St. Elsewhere" has its critics. Some call it soap opera, claiming it exaggerates the emotional side of hospital work and misses opportunities to provide health information. Rose Kushner, a breast cancer patient and author of "Alternatives," a recent book on breast cancer treatment, said the show "gives an overly optimistic portrayal of patient care," painting doctors and nurses as more empathetic than a hospital staff can realistically be.

Yet even its critics acknowledge that "St. Elsewhere" has made significant attempts to educate viewers on health issues. It ran an episode on a gay AIDS victim two years ago, well before Hollywood discovered the disease. It won a victory over the NBC censors to air a program dealing with testicular cancer. This season it took a couple through a complete medical workup for infertility, culminating in a test-tube fertilization that showed the moment of conception as seen through a microscope.

Consumer advocates say "St. Elsewhere's" greatest contribution to public knowledge about health care is its portrayal of doctors as less than perfect.

"It conveys the idea that . . . doctors are human beings and capable of making mistakes, that being sick and dying is a fairly grisly thing, and that you wind up having to have some sense of humor in order to cope with it," said Dr. Sidney Wolfe, director of the Ralph Nader-affiliated Health Research Group.

The hour-long series has survived four seasons of mediocre ratings on the appeal to advertisers of its loyal, mainly college-educated audience -- "some people might call them Yuppies," said NBC spokesman Brian Robinette. An estimated 18 million people tune in weekly -- a small audience for prime time. It has won five Emmys, including one in 1984 for outstanding writing in a drama series.

Despite producer John Masius' contention that "St. Elsewhere" is primarily a human drama "about people who happen to work in a hospital," the show has tackled an ambitious array of health-related topics.

Consider a sample from past episodes:

The mother of a mentally retarded, pregnant girl fights to obtain an abortion for her daughter.

A surgeon sexually harasses a nurse.

Dr. Fiscus befriends a homeless man, who dies suddenly from complications of an undiagnosed lung abscess.

Dr. Jack Morrison (played by David Morse), a sensitive young resident, is found to have a fraudulent medical degree.

An elderly Santa Claus handing out presents to children in the hospital lobby keels over and later dies of a heart attack.

A small boy's episodes of shortness of breath turn out to be panic attacks caused by his fear of nuclear war.

Dr. Donald Westphall (Emmy-winner Ed Flanders), the widowed chief of medicine, struggles to care for his autistic son.

Dr. Daniel Auschlander (Norman Lloyd) continues to work despite his own liver cancer.

The fare is too grim for some, but its dark mood is frequently lightened by flashes of inspired humor, wacky but oddly believable.

When Fiscus' homeless friend dies, he fulfills the man's wish for immortality by sneaking his stocking cap onto the head of an Egyptian mummy visiting the radiology department for a CT-scan. (The man had often admired the mummy at Boston's Museum of Fine Arts, which ordered the scan for research purposes.)

A regular character last season was Mrs. Hufnagel (Florence Halop), an infuriating although seriously ill patient who insulted every staff member she met, unwittingly sabotaging her own care. Mrs. Hufnagel expired in Dickensian style.

"She got killed when she got, I think, metabolically toxic, and they should have picked it up," recalled psychiatrist Bennett. "And she got more obnoxious, so they ignored her, and she groped around, and her bed ate her."

Mrs. Hufnagel's bed folded up with her inside it when she pushed the wrong button while trying to call a nurse. "That's funny and distressing and anxiety-provoking," said GW's Malakoff. "Patients like that really exist. It becomes a real issue for doctors . . . Here's this lady who complains, complains, complains, and everyone thinks she's a 'crock' . . . Then she comes in with something and nobody believes it . . . till it's ultimately too late."

"She was the consummate abused medical consumer, and they played that very well, except they showed it happening to one person instead of to 10 to 15 percent of the patients in a hospital," said Charles B. Inlander, executive director of the People's Medical Society, a consumer health organization.

Mrs. Hufnagel's demise illustrates several of the show's major themes: the fallibility of doctors, strained relations among staff or between doctors and patients, the daily mingling of humor and tragedy, and the ethical dilemmas inherent in the practice of medicine.

"They really bring out an ethical issue and struggle with it -- which doesn't always happen in real life," said Dr. Fitzhugh Mullan, a city hospital-trained physician and author of a book on his own battle with cancer. "From my experience on both sides of the stethoscope, I think the issues they raise are very patient-oriented."

The realistic flavor of "St. Elsewhere" owes much to the way episodes are structured. Several plot lines develop concurrently, some self-contained in one segment, others unfolding over weeks or months. Patients may check in and stay for several episodes or an entire season. Doctors and nurses come and go -- changing jobs, taking leaves of absence, sometimes even committing suicide. Residents move slowly through their medical training, gaining confidence, weathering personal crises and becoming more or less likable along the way.

"The original concept was to try to do an ensemble medical drama in a real way, with a kind of spontaneity and snap -- and comedy," said executive producer Bruce Paltrow. The idea was originated by Josh Brand and John Falsey, producers who left the show during the first season after insoluble conflicts with Paltrow and coproducers John Masius and Tom Fontana.

"Brand had a friend who was a resident at the Cleveland Clinic," said Masius. "They followed him around for three days with a tape recorder and took everything he said and put it in the pilot script."

The hospital set was designed from old photographs of St. Vincent's Hospital in New York, but Paltrow said Boston was chosen for the setting because of its wealth of hospitals and medical schools and its ethnic and socioeconomic mix. Viewers often assume St. Eligius is meant to suggest Boston City Hospital.

Paltrow said St. Eligius is a public hospital affiliated with a prestigious medical school but dedicated to caring for patients who have nowhere else to go. ("St. Elsewhere" is a derogatory hospital nickname sometimes used by real doctors on rounds in presenting the history of a patient newly arrived from another hospital that botched his or her care.)

"What we're trying to get across is that there are people working in places that don't have all the patina, yet who do great work and really care," Paltrow said.

The early episodes focused as much on disease as on character, said Robert Thompson, a graduate student at Northwestern University's department of radio, television and film, who has studied "St. Elsewhere." "Everyone had cancer, they were dying of it, it was a very depressing show." The ratings were dismal, and NBC ordered the show's producers to lighten up: paint the corridors a brighter color, move some of the action out of the hospital, introduce more comedy and romance.

The show was "too dark," admits Paltrow now. "It was Dostoyevskian."

Since Brand's and Falsey's departure, most story lines have originated with Masius and Fontana. Working under the supervision of Paltrow and Mark Tinker, the pair comes up with ideas and assigns them: approximately half to free-lancers, half to in-house story editors Channing Gibson, Charles Eglee and John Tinker. Almost always, the ideas center on dramatic situations between characters. Diseases and medical issues are secondary, chosen to fit each situation. Every script is extensively rewritten to make it conform with the overall format and to advance continuing plot lines.

In their office at MTM Productions in Studio City, Calif., Masius and Fontana talked about their view of medicine and its role in "St. Elsewhere."

"Masius has never been to a hospital," said Fontana. "I've done more of that." Fontana, a bearded, bespectacled easterner, has a mother who works as a unit coordinator at Millard Fillmore Hospital in Buffalo. His partner, a Scarsdale native who looks like a California surfer, added, "The only thing I've learned about medicine is that no one really knows."

The writers who flesh out the scripts generally have no medical background, although doctors have sometimes free-lanced for the show.

"The biggest problem . . . when we had doctors write the show was that the focus was: doctors did everything," said Fontana. "Nurses didn't exist. They so diminished the role of everyone else in the hospital."

For medical accuracy, they depend on Dr. Nancy Good, a Long Beach internist who serves as the show's medical adviser, and on Barbara Krause, a critical care nurse who is technical adviser on the set. Good works closely with story editors during the writing, choosing diseases and treatments that fit each story line and supplying medical dialogue. For specialized topics like in vitro fertilization, she consults experts.

In the initial version of a script, a line to be spoken by a surgeon may read, "Pass me the (medical bull----)," Fontana said. "That's where Nancy fills in."

The producers said they have learned to rely on a single adviser for accuracy because they find that, no matter what they write, doctors will take issue with treatments or drug dosages. The critics seldom agree even with each other. "If you do a story on prickly heat, you will get a letter from the National Prickly Heat Association thanking you or condemning you," Fontana said.

They take pains to be as accurate as possible. Medical terminology is spelled correctly in scripts, not phonetically, even though this sometimes leads to hilarious mispronunciations that slip by the editors. (Good's favorite was the "goo-yoo-ac test," one actor's butchering of the word "guaiac," which rhymes with "kayak" and is a test for hidden blood in stool.)

To the story editors, some medical treatments have become so familiar that writing about them is second nature. "We've done an awful lot of bypass surgery," said story editor Channing Gibson. "We've just learned about procedure in the ER by doing it over and over again . . . I could write out a code blue for you," the routine followed to treat a cardiac arrest.

The show strives to present both sides of ethical issues like abortion, said Paltrow, noting that in one episode a few years ago "we did a very poor job . . . dealing with Down's syndrome." A pregnant woman learned from an amniocentesis that her unborn child had the chromosome abnormality, which causes mental retardation, and chose to have an abortion.

Paltrow said columnist George F. Will, who has a child with Down's syndrome, wrote an angry letter to the show's producers. "Having felt we didn't do it fairly or to the best of our ability, we went on . . . and gave Westphall an autistic child," he said.

The writers are willing, however, to stretch medical reality to accommodate a plot. News that Dr. Bobby Caldwell, a promiscuous plastic surgeon, is destined to die this season of AIDS acquired from a female lover has provoked protests from some experts who point out that there is no conclusive proof that AIDS can be passed sexually from a woman to a man, and predict that the show will heighten irrational fear of the disease.

"Quite frankly, if I put a scare into the population about promiscuity . . . I have no problem with that," said Paltrow.

Added Gibson, "The fear is there, and it's real, and it is changing an entire group of people . . . Our point is to show the impact of Caldwell's illness on a character, to have Fiscus say, 'VD was no big deal when we were growing up -- sex was our birthright.' "

Another area where the show departs from reality is in its presentation of doctors' hospital training. "Those people are residents forever," complained Dr. Lawrence D'Angelo, chief of adolescent medicine at Children's Hospital in the District. "They do a little bit of everything."

Fontana said the residents are operating in "Fontana time": two TV seasons equals one year in the hospital. If the show runs for two more seasons, they will finish their three-year training program, and some characters are already talking on the show about their career plans.

But he believes that assigning residents to specific specialties would limit story possibilities. "It's the problem we find with a character like Caldwell," he said. "Medically, you could only tie him into plastic surgery stories."

Characters on St. Elsewhere continually develop both as people and physicians. For example, Dr. Jack Morrison, who in the first season seemed to be the Dr. Kildare of St. Eligius, has turned out to be the least self-confident resident. Last season his competence was questioned when he was found to have lied about his medical education. He survived to become a more intriguing personality. "You see what his frailty and sensitivity are rooted in," said Paltrow.

Several characters are common medical types, Paltrow said, even though none is based on a real doctor. Dr. Mark Craig, portrayed by Emmy-winning actor William Daniels, "is almost a cliche of certain types of heart surgeons . . . And Fiscus is a very classic resident: a little macho, horny, type A, unwilling to make certain types of commitments -- an emergency medicine personality, here today, gone tomorrow." Grandfatherly Dr. Auschlander, the doctor with liver cancer, is reminiscent of wise senior physicians at many medical schools. "We've always intended to kill him off, but whenever we think of it, we get very misty," said Fontana. "Also, the American Cancer Society has practically bronzed him, because it's the first show to have a person who has survived cancer."

"St. Elsewhere's" producers and writers are adamant that their first priority is to entertain rather than educate.

"When this show will fail is when it's done in a journalistic manner," said Gibson. "That is not our reason for being here. We're not a PBS documentary."

Nonetheless, the show's educational aspect has been rewarding. One much-acclaimed episode dealt with a college student's discovery that he had testicular cancer, and his successful treatment. The producers successfully argued with NBC censors to be allowed to use the word "testicle." Included was a scene about the need for men to examine themselves regularly for lumps that might indicate a testicular tumor, much as women are advised to check for breast cancer.

After the show aired, several viewers wrote saying they had examined themselves and found tumors. "When you get letters saying, 'You saved my life,' " Masius said, "it's incredibly gratifying."