Short Wave How Replaceable Are You?
Dec 10, 2025
Mary Roach, a witty science writer and author of Replaceable You, dives into the fascinating world of body part replacement. She discusses the challenges of replicating human tears, shares her experience inside an iron lung, and contrasts it with modern ventilators. Roach also explores innovative techniques like colon vaginoplasty and an unusual method of penis reconstruction using a finger. She paints a picture of bioprinting's potential, comparing it to the early days of aviation. Tune in for a humor-filled journey through the science of human replacement!
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Inside An Iron Lung
- Mary Roach describes being inside an iron lung and losing control over when she inhaled and exhaled.
- She lasted about seven minutes and noted the breathing felt relaxed but the head seal felt choking.
How Natural Breathing Works
- Breathing naturally is driven by negative pressure from diaphragm and rib muscles, not by forcing air in under pressure.
- The iron lung replicates this negative-pressure mechanism, unlike modern positive-pressure ventilators.
Tradeoffs Of Modern Ventilators
- Positive-pressure ventilators force air in via intubation and can leave lower lung areas underinflated.
- Extended sedation on positive-pressure support can cause cognitive issues, muscle deterioration, and lengthy rehab.
