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You're listening to the Nocturnous Conversations. I'm Emily Silverman.

If you've ever been to an ICU, you've probably seen a ventilator. It's a machine that helps someone breathe through a tube that goes through their mouth and into their trachea or windpipe. These days, ventilators are really advanced.

They can operate on closed feedback loops, adjusting the amount of air and frequency of breaths based on what the patient's body needs.

Working in the background, these devices are easy to take for granted.

But how did ventilators come to be?

Or further, how did intensive care units come to be with their hour-by-hour monitoring of patients

and their tight nursing ratios?

Today's guest, Dr. Hannah Wunsch, whisks us into 1950s Copenhagen so that we can learn about the origins of ventilators and the ICU.

It was a time and place when the city was fighting a devastating polio epidemic, which she explores in her book, The Autumn Ghost.

I found this piece of history to be gripping and love how Hannah guides us through the experiences

of doctors, nurses, medical students, patients, and families who are navigating this public

health crisis and taking big risks with innovation.

Hannah is a critical care physician and researcher at Sunnybrook Health Sciences Center.

She's a professor of anesthesiology and critical care medicine at the University of Toronto,

as well as a Canada research chair.

Before we dive in, let's hear Hannah reading an excerpt from her book, The Autumn Ghost.

August 1952, Copenhagen, Vivie.

Vivie Ebert was just 12 years old. She was going to die.

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