An Extant Hess Incubator on Display

To the Editor. The only surviving Hess incubator known to this author is currently on loan for display at the Spertus Museum in Chicago (Fig 1). A specimen from a forgotten era of neonatal medicine, this incubator belongs to the first generation of machines that led to the birth of early premature infant stations—the ancestors of modern neonatal intensive care units.1–3A popular story has it that Stéphane Tarnier (1828–1897), the renowned French obstetrician, conceived of “incubators” similar to “brooding hens” (coveuses), upon seeing the chicken hatchery at the Paris Zoo in 1878. He then asked Odile Martin, an instrument maker, to construct similar equipment for babies. Martin used an ingenious “thermosiphon” heating system, in which circulating hot water between a double-walled metallic cage warmed the air inside and could hold 2 premature babies. In 1880, the first set of Tarnier incubators was installed at the Paris Maternity Hospital, the world's first neonatal intensive care unit.2Over the next 3 decades, many incubators were developed incorporating the basic design features of the Tarnier incubator. In the early 1920s, Dr Julius Hess in Chicago designed an incubator in which he used electricity to generate hot water that circulated between the inner and outer walls of a metallic box. Hess made modifications to administer oxygen by free-flow. In May 1922, he founded the Premature Infant Station at Chicago's Sarah Morris Children's Hospital (of Michael Reese Medical Center)—the first such facility in the United States.4 Hess also developed the Ambulance Box—a miniature version of his incubator. Collaborating with the City of Chicago and the Chicago Yellow Cab Company, he organized an infant transportation program in Chicago at a time when only a handful of premature baby stations existed in the United States.The demonstration that incubators could save babies generated such great optimism among the professionals and the general public that incubators became symbols of great promise that all medical ills can be cured by machines—a tunnel vision prevalent even today.2,5 The incubators thus remain one of the most enduring symbols of the successes and (paradoxically) the failures of the modern neonatal intensive care.Although a large number of Hess incubators were used during the first half of the 20th century, only a few have survived. For decades, 1 specimen had been a hidden gem, on display in relative obscurity at Chicago's International Museum of Surgical Science. Only recently has its importance been brought into the spotlight. For now, it stands on a pedestal under a portrait of Dr Hess, polished and cleaned up, and it is a beauty to behold.