On a 20-below-zero night in 1965, nurse Caroline Rosdahl explained to a patient that he couldn't legally leave Hennepin County General Hospital because he was on a psychiatrist hold.

"Next thing I know, he's running down the third-floor hall with me right behind him," she recalled. "He crashed right through the window, landed unhurt on a snow-covered bush and didn't miss a beat — running down 7th Street in downtown Minneapolis."

Rosdahl called police, who asked how to identify the AWOL patient.

"Well, he'll be the only one running with an open-backed hospital gown and paper slippers," she said with a laugh. "It didn't take long before they brought him back."

That's just one of the anecdotes in Rosdahl's new self-published memoir, "The Naked City" — a title inspired by that night in the psych ward. (It's available on Amazon at tinyurl.com/NurseRosdahl).

Rosdahl, 83, recently retired after more than 50 years as a nurse, educator and textbook author. She used her pandemic isolation to chronicle a career that started as a teenage nursing aide in her hometown of Sauk Centre, through her years as Wright County's lone public health nurse in the early 1960s and the ensuing decades on hospital floors from Hennepin County to the University of Minnesota. Her cutting-edge use of behavioral objectives in nursing education in Anoka County led to 11 editions of "Textbook of Basic Nursing" — a widely used tome for student nurses.

"Textbooks are putzy; this project was a lot more fun," she said from her home in Plymouth.

At a time when appreciation for nurses — and the need to laugh — are both justifiably sky high, Rosdahl's tales prompt chuckles while offering a firsthand glimpse from health care's front lines.

There are plenty of awful memories, like an auto mechanic's blowtorch explosion that left him horribly burned. Or the autopsy she witnessed that revealed a young woman hadn't been pregnant, but thought she was — dying from drinking too much quinine to induce an abortion in the 1950s before the procedure was legalized.

Her humorous memories offset the heavy stuff. As a school nurse in the northern Minnesota town of Waubun, population about 400, she asked students to fill out index cards with their birth dates, parents' contact information, allergies and other basic information. In the small box labeled "Sex," where students were supposed to put "male" or "female," one girl jotted down: "Once in Waubun."

Writes Rosdahl: "It was a good thing it was only once, because that space on the card was very small."

Years later, admitting a woman to the hospital, Rosdahl ran through routine questions about last bowel movements and menstrual periods.

"When I asked her the next question on the list, 'Are you sexually active?' she looked around and then looked thoughtfully at the ceiling for several seconds. She then replied, in all seriousness, 'No, I pretty much just lie there!' "

Humor, Rosdahl insists, is as important a trait for nurses as compassion and anatomical know-how.

"If you don't have a sense of humor, it's almost impossible to work as a nurse because things often turn so sad," she said.

An only child, Rosdahl was born Caroline Bunker in 1937. Her father, Frank Bunker, dabbled in poetry and served as a Sauk Centre postman. He knew everyone in town — including Sauk Centre's literary lion, Nobel Prize-winning writer Sinclair Lewis and his father, Dr. E.J. Lewis, a town doctor.

Her introduction to nursing came as she suffered rheumatic fever at age 4. Idolizing her nurse, Mrs. Runion, little Caroline dreamed of following in her "Cuban-heeled white shoes."

Her father suffered a heart attack when she was 16. The principal pulled her from gym class, but a nun barred her from entering St. Michael's Hospital because her gym clothes were deemed inappropriate. Quietly seething, she went home to change.

She had applied to be a nursing aide at the hospital, which at the time was hiring only Catholic girls despite its standing as the Sauk Centre community hospital. One of the nuns, soon after the heart attack, called to offer her a job — saying later how the teenager impressed her by staying calm despite her fear and anger. Key nursing attributes.

"I was mad, but I must have been polite because I became the test case — the first Protestant girl hired as a nursing assistant," Rosdahl said.

She was on her way, literally writing the book on nursing through her popular textbooks. Twice married with one son and three stepchildren, Rosdahl is famous for more than nursing.

She always wanted to play saxophone or clarinet in a marching band, which wasn't possible for women when she first went to University of Minnesota in the mid-1950s. Back at the U, working on her doctorate in her late 30s, Rosdahl became the band's elder member in 1975 and still plays the clarinet.

Curt Brown's tales about Minnesota's history appear each Sunday. Readers can send him ideas and suggestions at mnhistory@startribune.com. His latest book looks at 1918 Minnesota, when flu, war and fires converged: http://strib.mn/MN1918.