Some people would say that DCI began when the doors to the first clinic were opened. Some would also say that's starting in the middle. The true beginning lies in the heartbreaks and successes of early dialysis. In 1943, during the time of World War II, Willem Kolff invented the first practical dialysis machine, the rotating drum. Kolff's invention was revised and redeveloped and even inspired others to create new dialysis machines and tools. By 1948 the Kolff-Brigham Dialysis Machine and the Skeggs Leonards Plate Dialyzer were created. In 1952 the Guarino and Guarino Artificial Kidney was developed. While the artificial kidney was a monumental development, at the time it had limited use because it had a very low blood volume and there was concern regarding the possibility of the dialyzing fluid leaking into the blood. At this same time in 1952 the Pressure Cooker Artificial Kidney by Inouye and Engleberg was being used. This was one of the first devices that allowed doctors to determine how much excess fluid was being drawn out of a patient's blood. In 1960 the Kiil Dialyzer was created in Norway by Dr. Fred Kiil. This type of device was used for overnight, unattended hemodialysis that was pioneered by Dr. Belding Scribner and his group in Seattle, Washington. Dr. Scribner and his team took matters one step further when they converted an old hotel into the first outpatient dialysis center, the Northwest Kidney Center, in Seattle, Washington.