Tidal Volume

The Rule

Two clauses, and everything in the book is measured against them. A thing breathes if it runs a two-phase cycle in which one phase is paid for and the other returns free out of a store. And it breathes only if running that cycle spends something it cannot get back.

The second clause is the one that does the cutting, and the sentence that carries it is this. Wear is what happens to a thing while it is being used. Breathing is what a thing has to keep doing to remain itself. A bellows wears out, and every stroke moves it nearer the day it stops sealing, but leave a bellows alone on its hook and it simply waits. Leave a lung alone and it stops being a lung within minutes.

Nine, Twelve, and One

Admitted: a human lung, a human heart, a Cepheid variable star, the terrestrial biosphere, yeast, a tide, the Asian monsoon, a geyser, and obligate anaerobes.

Refused: a market, a bellows, a fire, a breathing cave, a ringing planet, the water cycle, blown glass, bread, a balloon, a reed, a whistled language, and a ventilator.

Left open: the universe, refused provisionally on the state of the measurements at the time of writing, with the file kept open and the reason given.

The Four That Went Against the Author

Four verdicts came out against the answer the author wanted. The fire was refused when he would have admitted it, and so were the cave and the blown glass. A geyser was admitted over his objection. Those four are named in the book and the arguments that produced them are printed in full.

Twice the rule itself had to be rebuilt. The second clause turned out to say nothing useful about a tide, because interrupting a tide abolishes the tide, so the clause was split into two tests. The first clause had rested on the two phases taking turns until a fire and a yeast between them showed that turns were never the criterion, so it was rebuilt on the store. Both repairs are on the page. If you want to know whether a book is telling you the truth, look for the places where it lost an argument with itself and left the loss standing.

Copenhagen, August 1952

The Blegdam Hospital was admitting nearly fifty polio patients a day, and patients whose breathing muscles had failed were dying at a rate near eighty-seven percent. An anaesthetist named Bjorn Ibsen proposed opening the windpipe, fitting a rubber bag, and having a human being squeeze that bag by hand around the clock for as long as it took. On the twenty-seventh of August he was permitted to try it on one patient, a twelve-year-old girl named Vivi Ebert who was dying that afternoon.

It worked. Medical and dental students were recruited and sat beside the beds in shifts. Fifteen hundred of them took a turn before it was over, for a hundred and sixty-five thousand hours between them, and mortality was roughly halved within weeks. That is where the modern intensive care unit comes from. Not from an invention, but from a room full of nineteen-year-olds doing by hand what a body could no longer do for itself.

Table of Contents

Front Matter: Also by the Author · Copyright · Dedication · Epigraphs · Contents · A Note on the Method

Chapter Zero: The Test

Part One, What Breathes: One. The Paid Phase · Two. The Second Pump · Three. The Star That Keeps Time · Four. The Sawtooth · Five. Driven From Outside

Part Two, What Is Breathed: Six. A Breath You Can Hold · Seven. The Crumb · Eight. The Balloon · Nine. Bent Inward · Ten. Across the Ravine · Eleven. Aspirated

Part Three, Borrowed Lungs: Twelve. The Bag and the Bellows · Thirteen. The Wrong Direction · Fourteen. Smoke and Desperation · Fifteen. The Sigh and the Sneer

Part Four, What Fails: Sixteen. Remembering to Breathe · Seventeen. The Interrupted Night · Eighteen. The Poison Air · Nineteen. The Line at the Bedside · Twenty. The Exhale That Never Comes

End Matter: Acknowledgments · Appendix: The Verdicts · Glossary · A Note on Sources · Selected Bibliography · Questions for Discussion · Index · About the Author

The Epigraphs

“And the Lord God formed man of the dust of the ground, and breathed into his nostrils the breath of life; and man became a living soul.”

Genesis 2:7, Authorized Version, 1611.

“On a Universal Tendency in Nature to the Dissipation of Mechanical Energy.”

William Thomson, title of a paper read to the Royal Society of Edinburgh, 1852.

“Ondine's curse: failure of respiratory center automaticity while awake.”

John W. Severinghaus and Robert A. Mitchell, title of a clinical report, 1962.

A Note on the Free PDF

A book that spends four hundred and eighty-five pages arguing that a rule is only worth having if somebody runs it in public should be readable by anyone willing to check the work, so the full text is here at no charge. The reading edition is a formatted PDF with embedded fonts, a navigation panel, a page-numbered table of contents, and a full index whose page numbers were resolved for that edition rather than copied from the print one. The whole book is here, Chapter Zero through the index. Download it, read it, and run the rule yourself against something the book never considered.

Dedication

For Janna,

and for the fifteen hundred students in Copenhagen who breathed for strangers by hand, in shifts, for as long as it took.