History[edit]

The English nurse Florence Nightingale pioneered efforts to use a separate hospital area for critically injured patients. During the Crimean War in the 1850s, she introduced the practice of moving the sickest patients to the beds directly opposite the nursing station on each ward so that they could be monitored more closely.^[14] In 1923, the American neurosurgeon Walter Dandy created a three-bed unit at the Johns Hopkins Hospital. In these units, specially trained nurses cared for critically ill postoperative neurosurgical patients.^[15][14]


The Danish anaesthesiologist Bjørn Aage Ibsen became involved in the 1952 poliomyelitis epidemic in Copenhagen, where 2722 patients developed the illness in a six-month period, with 316 of those developing some form of respiratory or airway paralysis.^[16] Some of these patients had been treated using the few available negative pressure ventilators, but these devices (while helpful) were limited in number and did not protect the patient's lungs from aspiration of secretions. Ibsen changed the management directly by instituting long-term positive pressure ventilation using tracheal intubation, and he enlisted 200 medical students to manually pump oxygen and air into the patients' lungs round the clock.^[17] At this time, Carl-Gunnar Engström had developed one of the first artificial positive-pressure volume-controlled ventilators, which eventually replaced the medical students. With the change in care, mortality during the epidemic declined from 90% to around 25%.^[18][19] Patients were managed in three special 35-bed areas, which aided charting medications and other management.


In 1953, Ibsen set up what became the world's first intensive care unit in a converted student nurse classroom in Copenhagen Municipal Hospital. He provided one of the first accounts of the management of tetanus using neuromuscular-blocking drugs and controlled ventilation.^[20] The following year, Ibsen was elected head of the department of anaesthesiology at that institution. He jointly authored the first known account of intensive care management principles in the journal Nordisk Medicin, with Tone Dahl Kvittingen from Norway.^[21]


For a time in the early 1960s, it was not clear that specialized intensive care units were needed, so intensive care resources were brought to the room of the patient that needed the additional monitoring, care, and resources. It became rapidly evident, however, that a fixed location where intensive care resources and dedicated personnel were available provided better care than ad hoc provision of intensive care services spread throughout a hospital. In 1962, in the University of Pittsburgh, the first critical care residency was established in the United States. In 1970, the Society of Critical Care Medicine was formed.^[22]