Extracorporeal Membrane Oxygenation, or ECMO, is a form of life support that oxygenates and pumps a patient’s blood outside the body, allowing failing hearts or lungs a chance to rest and recover. Roach presents ECMO as a technology that expands the possibilities of care, bridging patients toward transplants or other treatments. The book details its expanding applications, from an “ECMOBile” that makes emergency house calls to ambulatory ECMO that allows rehabilitating patients to walk while connected to the machine. This concept is closely linked to the lab work on ex vivo organ perfusion, in which hearts are kept viable outside a body for extended periods, enabling evaluation and repair.

FRESH, an acronym for Freeform Reversible Embedding of Suspended Hydrogels, is a 3D bioprinting method that addresses the challenge of creating soft, complex biological structures. The author explains how its inventor, Adam Feinberg, developed a process wherein biological inks are extruded into a temporary gel support bath, which prevents the delicate construct from collapsing under its own weight. This technique allows for the creation of intricate tissues by using different “inks” for collagen scaffolding and live cells, which solidify upon contact with the gel. Roach uses tangible examples from Feinberg’s lab, such as a printed artery and millimeter-thick heart constructs that beat synchronously, to show both the promise and current limitations of the technology. The process exemplifies the hype around the procedure, contrasting with the seemingly endless obstacles involved with such a cutting-edge field.

Induced pluripotent stem cells, or iPSCs, are adult cells that have been regressed to the state they exist in as blastocysts, the earliest stage of an embryo. These are cells that do not yet have any specific function within the body. They have the capability to become any type of human cell—skin cells, neurons, platelets, etc.—depending on cues they receive from DNA and their environment. 

Roach positions this technology as a cornerstone of the future of regenerative medicine, connecting disparate topics like bioprinting and hair restoration. The book traces the origin of iPSCs to researcher Shinya Yamanaka, who discovered a way “to regress adult cells to their undifferentiated state” (215), making it possible to generate replacement tissues from a patient’s own body. This concept surfaces throughout the narrative, from the potential to create new dopamine-producing neurons for Parkinson’s patients to the central goal of growing new hair follicles. The discussion also highlights a key logistical and economic challenge: the trade-off between creating costly, bespoke iPSCs for each patient to avoid immune rejection versus developing universal “stealth” cell lines that would be cheaper but carry different risks.

The concept of skin grafting encompasses a family of techniques—autograft, allograft, and xenograft—that Roach uses to explore the nuances of what it means to “replace” a body part. The book clearly differentiates between an autograft, a permanent fix using the patient’s own skin, and other grafts that act as temporary coverings. Allografts, from another human, and xenografts, from another species, function as biological dressings that protect a wound before a permanent solution is possible. 

As Roach notes, a foreign graft “may be called a graft, but more accurately, it’s a kind of dressing—a biodressing” (21). The text explains how, in the immunosuppressed state of a severe burn victim, these temporary grafts can “take” for a few days. However, it also focuses on the significant human cost of these procedures, revealing how supply limits force surgeons to harvest skin from sensitive or unconventional areas like the scalp, soles of the feet, and scrotum, often requiring painful reharvesting as the patient heals.