Patients could not undergo dialysis treatment indefinitely due to the glass shunts that were used in the treatment. The shunts caused damage to veins and arteries to such a degree that long term dialysis was impossible.
Dialysis at that time was used only to stabilize a patient. If the kidneys did not begin to function properly the patient would eventually die of kidney failure. In , Dr. Belding H. Scribner and his team at the University of Washington modified glass dialysis shunts by making them from Teflon. The teflon Scribner Shunt worked by keeping the circulatory access open after dialysis treatment.
Whenever necessary, the kidney dialysis machine could be attached to the tube without damaging the veins or arteries. Scribner received the Gairdner Foundation International Award in , and the Albert Lasker Award in for major contributions to medical science.
Sinai Hospital in New York. In the late s, Kolff came to the United States, where he continued his research. At Mt. Therefore, Kolff and his colleagues were forced to perform dialysis in a surgical suite after hours. The next few years saw many strides in dialysis.
During the Korean War, Kolff-Brigham dialyzers were instrumental in the treatment of injured American soldiers. In mid 20 th century America, doctors believed it was impossible for patients to have dialysis indefinitely for two reasons. First, they thought no man-made device could replace the function of kidneys over the long term.
Belding Scribner, a young professor of medicine at the University of Washington, came up with the idea of connecting the patient to the dialyzer using plastic tubes, one inserted into an artery and one into a vein.
After treatment, the circulatory access would be kept open by connecting the two tubes outside the body using a small U-shaped device, which would shunt the blood from the tube in the artery back to the tube in the vein. The Scribner Shunt, as it was called, was developed using the newly introduced material, Teflon. A German doctor by the name of Georg Haas, from the town of Giessen near Frankfurt am Main, performed the first dialysis treatments involving humans.
It is believed that Haas dialyzed the first patient with kidney failure at the University of Giessen in the summer of , after performing preparatory experiments.
By , Haas had dialyzed an additional six patients, none of whom survived, likely because of the critical condition of the patients and the insufficient effectiveness of the dialysis treatment.
The Haas Dialyzer, which also used a Collodion membrane, was built in a variety of models and sizes. Haas, like Abel, also used hirudin as the anticoagulant in his first dialysis treatments. However, this substance often led to massive complications arising from allergic reactions because it was not adequately purified and originated from a species very distant from humans. In the end, Haas used heparin in his seventh and final experiment.
Heparin is the universal anticoagulant in mammals. This substance caused substantially fewer complications than hirudin — even when it was insufficiently purified — and could be produced in much larger amounts.
Following the development of better purification methods in , heparin was adopted as the necessary anticoagulant, and continues to be used today. In fall , Willem Kolff, of the Netherlands, made the breakthrough that had stubbornly eluded Haas. Kolff used a rotating drum kidney he had developed to perform a week-long dialysis treatment on a year-old patient who had been admitted to hospital with acute kidney failure.
The patient was subsequently discharged with normal kidney function. This patient proved that the concept developed by Abel and Haas could be put into practice and thus represented the first major breakthrough in the treatment of patients with kidney disease.
The success was partially due to the technical improvements in the actual equipment used for the treatment. Examples of the Kolff rotating drum kidney crossed the Atlantic and arrived at the Peter Brent Brigham Hospital in Boston, where they underwent a significant technical improvement. The modified machines became known as the Kolff-Brigham artificial kidney, and between and were shipped from Boston to 22 hospitals worldwide.
The Kolff-Brigham kidney had previously passed its practical test under extreme conditions during the Korean War. Dialysis treatment succeeded in improving the average survival rate of soldiers suffering from post-traumatic kidney failure and thus won time for additional medical procedures.
One of the most important functions of the natural kidney, in addition to the filtering of uremic toxins, is the removal of excess water. When the kidneys fail, this function must be taken over by the artificial kidney, which is also known as a dialyzer. The procedure by which plasma water from the patient is squeezed through the dialyzer membrane using pressure is termed ultrafiltration. In , Swede Nils Alwall published a scientific work describing a modified dialyzer that could perform the necessary combination of dialysis and ultrafiltration better than the original Kolff kidney.
The cellophane membranes used in this dialyzer could withstand higher pressure because of their positioning between two protective metal grates. All the membranes were in a tightly sealed cylinder so that different pressure ratios could be generated.
By proving that uremic patients could be successfully treated using the artificial kidney, Kolff sparked a flurry of activity around the world to develop improved and more effective dialyzers.
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