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The earliest known theories and attempts to create an artificial kidney machine came about in the late 1800s. A major problem in the early research was that the available anticoagulant (medication used to prevent clotting in blood), hirudin, which was obtained from leach heads, was found to be unsafe for use. Heparin, another anticoagulant, was discovered in 1922. Although it was used as an anticoagulant for blood samples in the 20s and 30s, it wasn't until the early 40's that is was successfully used as a systemic anticoagulant in humans.
The first workable artificial kidney was developed during World War II in 1944-1945 by Dr. Willem Kolff, who was living in German occupied Holland. This device resembled a drum barrel made of slats with open spaces between the slats. Cellophane "sausage" casing was wound around the drum. The lower portion of the drum, which was suspended length-wise in a half barrel reservoir, was lowered in a dialysis bath. This procedure required a large volume of blood circulation outside the body during dialysis and required priming with blood transfusions. Either metal tubes or glass tubing was used to create a blood access, in an artery and a vein, and could be used only once per pair of blood vessels. Neither blood pumps nor plastic tubing was used to connect the blood accesses to the cellulose sausage casing. Rotating Ford water pumps permitted the drums to rotate at either end, enabling the blood to flow through. Blood was"pumped" using the patient's heart and blood pressure into the cellulose casing, and was propelled from one end of the drum to the other, by the turning of the drum. Blood was then collected in a glass cylinder with an open nipple at the lower end. This was connected by rubber tubing to the patient's venous access. By alternating lowering and raising the cylinder, blood was collected and drained back into the patient's vein.
Following WW II, Dr. Kolff migrated to the United States, bringing three of these machines with him. The machines were used in this country as models for more advanced "rotating drums." This pioneer of the first "artificial kidney" also developed the next generation of machines, known as the "twin coil" dialyzer. These devices used disposable tubing and dialyzers, and were instrumental in saving many patients who suffered from acute renal failure from crush injuries, war injuries (during the Korean War) and following exposure to nephrotoxins.
The major problem that prevented consideration of using dialysis for treatment of patients with End Stage Renal Disease (ESRD) was that there was no means to establish a "permanent" blood access. In the mid-50s, teflon and silastic were invented. These proved to be relatively safe plastics, and they enabled Dr. Belding Scribner to create the first tubing that served as a "permanent," at least long lasting, blood access.
In the 1960s, many advances were made in hemodialysis. The first outpatient hemodialysis center was established in Seattle, in 1962. Home hemodialysis was also begun. In 1965, the arterio-venous (A-V) fistula was developed by Brescia and Cimino, providing another type of permanent access. In 1966, the hollow fiber dialyzer was developed and represented a great improvement over previous versions.
It was not until the 1960s that peritoneal dialysis was considered to be an alternative treatment to hemodialysis, although experiments with peritoneal dialysis began in the 1920s. many problems, such as peritonitis (infection) and access development difficulties, prevented peritoneal dialysis from becoming a successful form of treatment for chronic renal failure. In 1968, Tenchkhoff developed a cuffed, indwelling, silastic catheter which greatly reduced the problems related to peritoneal dialysis access. Prior to this time the patient was required to endure a new puncture of the abdominal wall each time this treatment was performed.
.gif) Despite the growth of dialysis in the 1960s, dialysis programs were limited in number and size, and every patient who needed dialysis was not accepted. It was necessary for hospitals to form patient selection committees to choose which patients would go on dialysis and which ones would not. It was necessary for patients to meet very rigid requirements to be chosen. Landmark legislation in 1972 made it possible for Medicare to pay for 80% of treatment costs for both dialysis and transplant patients. This new law removed financial barriers to treatment and helped dialysis facilities expand with more equipment for patients. Patient selection committees became a thing of the past.
In the late 1970s and early 1980s, the use of intermittent peritoneal dialysis (IPD) declined as continuous ambulatory peritoneal dialysis (CAPD) and continuous cyclic peritoneal dialysis (CCPD) were developed. Advancements in peritoneal catheters, devices to decrease contamination during exchanges, and development of automated equipment, continued into the 1990's to make peritoneal dialysis more efficient. In the 1980s-1990s, computerized hemodialysis machines, better dialyzers, and improved monitoring and safety devices reduced treatment times, gave doctors better ways to monitor treatment, and made possible a more normal life for patients. In 1989 a major breakthrough was the introduction of a drug to combat anemia in dialysis patients. Epogen, has given new energy and stamina to those patients.
Due to the may advancements made in dialysis therapy, ESRD patients can now lead healthier, more normal lives. Research and development continue to improve the quality of care of ESRD patients.
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