INTENSIVE CARE The Story of a Nurse By Echo Heron Atheneum. 370 pp. $18.95

"A nurse is a person of many faces," a senior instructor told Echo Heron on the day she graduated from nursing school. "You are a warrior against death and suffering, a technician of the highest degree; you are a mother, a sister, a best friend, a psychiatrist; you are a teacher, a magician, a sounding board, a secretary, a fortune teller, a politician, but most of all, you are a loving human being who has chosen to give that love in one of the best ways you can."

Heron attempts to capture the multifaceted world of modern nursing in her passionate and detailed memoir, "Intensive Care: The Story of a Nurse." She chronicles her own voyage from idealistic nursing student through the gritty realities of practice to burnout and renewal with humor and a fine eye for detail. When she focuses on the pale hand of a 4-year-old drowning victim or the cockroach scuttling from a bag lady's hair, her scenes come alive.

Unfortunately, as the heroine of her own story, Heron too frequently paints a self-congratulatory, melodramatic picture with unbelievable dialogue, one-dimensional characters and wooden writing. This approach results in lines like "The familiar subtle thrill began to well up inside me as I walked to the nurse's station" and "She was a woman who'd loved, laughed, hated, and cried; she had walked in the rain, eaten chocolate ice cream cones, comforted a friend in need, and ridden bicycles."

Heron is at her best when describing day-to-day life in a busy California hospital. Her vivid portrayal of an attractive socialite who had been hiding a putridly decomposing breast from her husband and friends is shockingly believable. Her accounts of the 8-year-old who swears like a sailor, the crotchety patient with Fluff-My-Pillow Syndrome and the nursing students frantically practicing injections on oranges are humorous and lively.

Yet too often she obscures her story with unnecessary jargon, such as syncopal episodes, rings of necrosis, exsanguinate, aspirate and meatus. Also, her effort to protect individuals' privacy by changing names and creating composite characters frequently results in cardboard stereotypes. One example is Dr. Drigely, the fat, saliva-spraying surgeon who risks the loss of a teen-ager's leg rather than miss a sailing lesson. Another is Miss Telmack, the rigid, cold nursing instructor who orders Heron to inject a dying man with morphine to ease his pain, knowing that the drug could suppress his breathing to a life-threatening degree.

Heron skims some of the most important issues in modern nursing -- pay equity, unionization and authority for patient care. In her right-minded view, she perceives problems in black and white, with scant regard for the subtle complexities inherent in high-tech medicine.

She also hints at, rather than tells, details of her personal life. She mentions an abusive, alcoholic mother and a childhood as a frequent runaway, yet never clarifies the story. Her early marriage to a law student gets a few short lines, and her son Simon is portrayed as an angelic cherub through most of the book and a surly adolescent toward the end. We hear constantly about her ulcer and reliance on Tylenol and Tagamet, yet her eventual psychological problems and recovery are tossed off in a confusing section that lends little insight to the dilemma of nurse burnout.

She is eloquent, however, on the problem of physicians and family members who refuse to let terminal patients die in peace. In a chilling anecdote about a man she calls Turk, Heron poignantly describes how the dying man's pleas to avoid the pain and indignity of arm restraints, chest tubes and electric shocks are ignored by a stubborn and guilt-plagued son who insists that the doctors use any available techniques to try and save his 84-year-old father.

"Please. Stop this," Turk writes to Heron from his nest of tubes, lines and catheters. "Not right ... want to die without all this. Torture."

Eventually, Heron refuses to continue cardiopulmonary resuscitation on Turk. Death, she decides, has two faces. The "ultimate thief" and the "kind rescuer."

Nurses must do more than just help people get well, Heron concludes. "Freeing people of the pain from which there was no other release but death," she writes, "was another part of nursing."

The reviewer is a Washington Post editor on leave to write a novel.